{"title":"Airtight Membranes \u0026 Airtightness Products","description":"\u003cp\u003eEverything you need to make a building airtight, in one place. Our airtightness products work as one system: \u003cstrong\u003eliquid airtight membranes\u003c\/strong\u003e for walls, floors and ceilings, \u003cstrong\u003eairtightness tape\u003c\/strong\u003e for windows, doors and junctions, \u003cstrong\u003eairtight sealants and grommets\u003c\/strong\u003e for gaps and service penetrations, and \u003cstrong\u003esmoke testing kit\u003c\/strong\u003e for finding leaks before the air test does.\u003c\/p\u003e\n\u003ch2\u003eLiquid airtight membranes\u003c\/h2\u003e\n\u003cp\u003e\u003ca href=\"\/products\/passive-purple-internal-airtight-vapour-control-paint-11-4kg\"\u003ePassive Purple\u003c\/a\u003e and \u003ca href=\"\/products\/airtight-white-membrane-paint\"\u003eAirtight White\u003c\/a\u003e are airtight membranes you spray, roller or brush straight onto blockwork, OSB, plasterboard and concrete. They cure into one continuous airtight and vapour control layer with no laps to tape and no staples to puncture it. Both are Passivhaus certified, BBA approved, tested to ASTM and EN standards (ICC-ES ESR-4715) and tested as radon and methane barriers. For façades and external walls, \u003ca href=\"\/products\/passive-purple-external-airtight-fire-rated-facade-waterproofing-membrane-10kg-cream-spray-roller\"\u003ePassive Purple External\u003c\/a\u003e is a fire rated (Class B) airtight and weatherproof membrane, and \u003ca href=\"\/products\/passive-purple-x-10kg-white-spray-roller\"\u003ePassive Purple X\u003c\/a\u003e brings Class B fire performance to the internal airtight layer. For existing buildings, the \u003ca href=\"\/collections\/retrofit-vapour-barrier-membrane\"\u003eRetrofit Airtightness\u003c\/a\u003e paints seal walls and ceilings without stripping back.\u003c\/p\u003e\n\u003ch2\u003eAirtightness tape\u003c\/h2\u003e\n\u003cp\u003e\u003ca href=\"\/products\/airtight-tapes\"\u003eIM Fleece Airtightness Tape\u003c\/a\u003e connects window and door frames, board joints and building junctions to the airtight layer. It has a plasterable fleece face and comes in 25m rolls in 75mm, 100mm, 150mm and 200mm widths. See our \u003ca href=\"\/blogs\/educational\/airtightness-tape-guide\"\u003eairtightness tape guide\u003c\/a\u003e for choosing, sizing and installing it.\u003c\/p\u003e\n\u003ch2\u003eAirtight sealants and grommets\u003c\/h2\u003e\n\u003cp\u003e\u003ca href=\"\/products\/passivhaus-airtight-sealant\"\u003ePassivhaus Airtight Sealant\u003c\/a\u003e seals gaps, junctions and the edges of the membrane. \u003ca href=\"\/products\/the-goat-sealant-airtight-flexible-sealant\"\u003eThe GOAT Liquid Grommet\u003c\/a\u003e forms an airtight, flexible seal around pipes and cables straight from the tube, so you don't need a different grommet for every service size.\u003c\/p\u003e\n\u003ch2\u003eFind leaks before the air test\u003c\/h2\u003e\n\u003cp\u003eThe \u003ca href=\"\/products\/wohler-smoke-stick\"\u003eWohler S 100 Smoke Stick\u003c\/a\u003e and \u003ca href=\"\/products\/wohler-smoke-tanks-packof3\"\u003esmoke tanks\u003c\/a\u003e show you exactly where air is getting through, so you can fix it before the tester arrives. Read \u003ca href=\"\/blogs\/educational\/how-to-pass-an-airtightness-test-the-pre-test-checklist\"\u003ehow to pass an airtightness test\u003c\/a\u003e.\u003c\/p\u003e\n\u003ch2\u003eAirtightness questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is an airtight membrane?\u003c\/strong\u003e\u003cbr\u003eAn airtight membrane is a continuous layer that stops air leaking through the building fabric. A liquid airtight membrane is painted or sprayed on, so it follows every corner, joint and penetration without laps. Read more in \u003ca href=\"\/blogs\/educational\/how-to-make-a-building-airtight\"\u003ehow to make a building airtight\u003c\/a\u003e.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat airtightness do I need?\u003c\/strong\u003e\u003cbr\u003eBuilding Regulations Part L sets a maximum air permeability for new homes, and Passivhaus targets 0.6 air changes per hour at 50 Pa. See \u003ca href=\"\/blogs\/educational\/airtightness-and-part-l-uk-air-permeability-targets-explained\"\u003ePart L air permeability targets explained\u003c\/a\u003e and \u003ca href=\"\/blogs\/educational\/how-to-achieve-0-6-ach-hitting-the-passivhaus-airtightness-target\"\u003ehow to hit 0.6 ACH\u003c\/a\u003e.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eTape or liquid membrane?\u003c\/strong\u003e\u003cbr\u003eMost projects use both: liquid membrane across the surfaces and tape at frames and board joints. See \u003ca href=\"\/blogs\/educational\/airtightness-tape-vs-liquid-airtight-membrane\"\u003eairtightness tape vs liquid airtight membrane\u003c\/a\u003e.\u003c\/p\u003e\n\u003cp\u003eNot sure what your project needs? \u003ca href=\"\/pages\/contact\"\u003eSend us your drawings\u003c\/a\u003e or call our technical team on 01223 208174.\u003c\/p\u003e\n","products":[{"product_id":"airtight-tapes","title":"IM Fleece Airtightness Tape for Windows \u0026 Junctions","description":"\u003cp\u003e\u003cstrong\u003eIM Fleece Airtightness Tape\u003c\/strong\u003e connects window and door frames, board joints and building junctions to the surrounding air barrier. Its self-adhesive backing and plasterable fleece face help create a neat, continuous seal in new-build and retrofit construction.\u003c\/p\u003e\n\u003cp\u003eChoose a 25m roll in \u003cstrong\u003e75mm, 100mm, 150mm or 200mm width\u003c\/strong\u003e, with single-roll and box options available above. Select the width to suit the junction, the required bonded area on each surface and the movement allowance in your project detail.\u003c\/p\u003e\n\u003ch2\u003eChoose tape for the detail\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eWindows and doors:\u003c\/strong\u003e connect the frame to the designed airtight layer around the reveal.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBoard and membrane joints:\u003c\/strong\u003e use where the substrate and adjoining membrane are confirmed as compatible.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRetrofit junctions:\u003c\/strong\u003e bridge changes of material after making the surfaces sound and preparing a suitable bonding area.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePlastered finishes:\u003c\/strong\u003e the fleece face accepts compatible plaster or paint as specified in the installation detail.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe tape has a modified polyamide film and nonwoven fleece construction with moisture-dependent vapour resistance. Airtightness and vapour control are different requirements: confirm the complete wall or roof build-up when selecting the tape and adjoining membrane.\u003c\/p\u003e\n\u003ch2\u003ePrepare and apply correctly\u003c\/h2\u003e\n\u003col\u003e\n\u003cli\u003eUse sound, dry surfaces free from dust, grease and loose material. Check adhesion on the actual substrate and use a suitable primer where required.\u003c\/li\u003e\n\u003cli\u003eApply between \u003cstrong\u003e+5°C and +40°C\u003c\/strong\u003e. Do not bond to wet or damp surfaces.\u003c\/li\u003e\n\u003cli\u003ePeel back the release liner progressively, leave the required movement allowance and press the bonded area firmly with a roller.\u003c\/li\u003e\n\u003cli\u003eOverlap tape joins by at least \u003cstrong\u003e50mm\u003c\/strong\u003e and inspect corners and ends for open paths.\u003c\/li\u003e\n\u003cli\u003eConnect the tape into the adjoining air barrier using the specified compatible detail. Inspect before covering and protect exposed tape within the stated 12-month UV limit.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003eThese are selection notes, not a substitute for the \u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/AIRTIGHT_FLEECE_TAPE_PRODUCT_SHEET_1.pdf?v=1771421234\"\u003eIM Fleece Tape technical data sheet\u003c\/a\u003e and \u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/AIRTIGHT_FLEECE_TAPE_INSTALL_GUIDE.pdf?v=1771424163\"\u003einstallation guide\u003c\/a\u003e. Ask our technical team to confirm primer, substrate and membrane compatibility for your junction.\u003c\/p\u003e\n\u003ch2\u003ePart of a complete airtight system\u003c\/h2\u003e\n\u003cp\u003eUse the tape at suitable linear junctions and \u003ca href=\"\/products\/passive-purple-internal-airtight-vapour-control-paint-11-4kg\"\u003ePassive Purple liquid airtight membrane\u003c\/a\u003e across the specified surrounding surface. Follow the approved interface detail, coating coverage and curing instructions. Choosing a tape alone does not guarantee a whole-building air-test result or establish a radon-resistant detail.\u003c\/p\u003e\n\u003ch2\u003eFind the right guide\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/airtightness-tape-guide\"\u003eAirtightness tape: selection, sizing and installation basics\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/why-im-fleece-airtight-tape-is-the-best-choice-for-retrofit-airtightness-window-sealing-and-passivhaus-projects\"\u003eChoosing airtight tape for windows, doors and retrofit\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/sealing-window-and-door-frames-airtight-with-fleece-tape\"\u003eHow to install fleece tape around window and door frames\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/why-airtightness-tape-peels-off\"\u003eWhy airtightness tape peels off and how to repair it\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/airtightness-tape-vs-liquid-airtight-membrane\"\u003eWhere to use tape and where to use liquid membrane\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eReady to order?\u003c\/strong\u003e Select your width and pack size above. For an unusual junction, \u003ca href=\"\/pages\/contact\"\u003econtact our technical team\u003c\/a\u003e before installation.\u003c\/p\u003e","brand":"Intelligent Membranes","offers":[{"title":"75mm x 25m (Single Roll)","offer_id":52608799670612,"sku":"IM\/00AFT75","price":40.0,"currency_code":"GBP","in_stock":true},{"title":"75mm x 25m (Box of 5)","offer_id":52608799703380,"sku":"IM\/00AFT75-B5","price":157.5,"currency_code":"GBP","in_stock":true},{"title":"100mm x 25m (Single Roll)","offer_id":52608799736148,"sku":"IM\/00AFT100","price":50.0,"currency_code":"GBP","in_stock":true},{"title":"100mm x 25m (Box of 4)","offer_id":52608799768916,"sku":"IM\/00AFT100-B4","price":165.0,"currency_code":"GBP","in_stock":true},{"title":"150mm x 25m (Single Roll)","offer_id":52608799801684,"sku":"IM\/00AFT150","price":75.0,"currency_code":"GBP","in_stock":true},{"title":"150mm x 25m (Box of 2)","offer_id":52608799834452,"sku":"IM\/00AFT150-B2","price":111.75,"currency_code":"GBP","in_stock":true},{"title":"200mm x 25m (Single Roll)","offer_id":52608799867220,"sku":"IM\/00AFT200","price":100.0,"currency_code":"GBP","in_stock":true},{"title":"200mm x 25m (Box of 2)","offer_id":52608799899988,"sku":"IM\/00AFT200-B2","price":135.75,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Airtight_tape.png?v=1784733293"},{"product_id":"airtight-white-membrane-paint","title":"Airtight White - Vapour Control, Airtight \u0026 Smoke Tight Paint (11.4kg) - Spray \/ Roller Applied","description":"\u003ch2 data-start=\"93\" data-end=\"127\"\u003ePassive Purple Airtight White\u003c\/h2\u003e\n\u003cp data-start=\"128\" data-end=\"180\"\u003e\u003cstrong data-start=\"128\" data-end=\"180\"\u003eVOC-Free Airtight, Vapour \u0026amp; Gas Control Membrane\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-start=\"182\" data-end=\"389\"\u003ePassive Purple Airtight White is a \u003cstrong data-start=\"217\" data-end=\"260\"\u003eVOC-free, water-based airtight membrane\u003c\/strong\u003e providing reliable \u003cstrong data-start=\"280\" data-end=\"298\"\u003evapour control\u003c\/strong\u003e and protection against \u003cstrong data-start=\"322\" data-end=\"349\"\u003eradon and methane gases\u003c\/strong\u003e — without any nasty chemicals or fumes.\u003c\/p\u003e\n\u003cp data-start=\"391\" data-end=\"687\"\u003eIdeal for those on-site “oops” moments, it can be applied directly onto \u003cstrong data-start=\"463\" data-end=\"479\"\u003eplasterboard\u003c\/strong\u003e if a vapour control layer has been missed. When used with \u003cstrong data-start=\"538\" data-end=\"551\"\u003eIM Primer\u003c\/strong\u003e, it can be \u003cstrong data-start=\"563\" data-end=\"595\"\u003eleft on show or painted over\u003c\/strong\u003e, making it perfect for exposed environments such as \u003cstrong data-start=\"648\" data-end=\"686\"\u003ecar parks, museums, and stairwells\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cp data-start=\"689\" data-end=\"910\"\u003eOnce dry, it forms a \u003cstrong data-start=\"710\" data-end=\"749\"\u003etough yet flexible polymer membrane\u003c\/strong\u003e that moves with the building and resists impact damage — eliminating the rips, tears, staple holes and failed tapes associated with traditional paper membranes.\u003c\/p\u003e\n\u003cp data-start=\"912\" data-end=\"954\" data-is-last-node=\"\" data-is-only-node=\"\"\u003eLess labour. Less waste. More performance.\u003c\/p\u003e\n\u003cp data-start=\"912\" data-end=\"954\" data-is-last-node=\"\" data-is-only-node=\"\"\u003eCheck out our \u003ca href=\"https:\/\/intelligentmembranes.aflip.in\/80f3ef4f93.html\" target=\"_blank\" title=\"Retrofit Vapour control \" rel=\"noopener\"\u003ecase study \u003c\/a\u003e\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eLeft on show — see it in 360°\u003c\/h2\u003e\n\u003cp\u003eA museum project where Airtight White is doing both jobs at once: the airtightness and vapour control layer on the concrete panel walls, and the finished surface that stays on view.\u003c\/p\u003e\n\u003cfigure style=\"margin:20px 0;padding:0;\"\u003e\n\u003cdiv style=\"position:relative;padding-top:56.25%;background:#f4f4f4;border-radius:6px;overflow:hidden;\"\u003e\u003ciframe src=\"https:\/\/kuula.co\/share\/LnD57?logo=1\u0026amp;info=1\u0026amp;fs=1\u0026amp;vr=0\u0026amp;zoom=1\u0026amp;sd=1\u0026amp;thumbs=1\" title=\"Airtight White left on show as the finished surface, museum project — 360 degree site tour\" loading=\"lazy\" frameborder=\"0\" scrolling=\"no\" allow=\"xr-spatial-tracking; gyroscope; accelerometer\" allowfullscreen=\"\" style=\"position:absolute;top:0;left:0;width:100%;height:100%;border:0;\"\u003e\u003c\/iframe\u003e\u003c\/div\u003e\n\u003cfigcaption style=\"margin-top:10px;font-size:0.9rem;\"\u003eClick and drag to look around. \u003ca href=\"\/pages\/360-images\"\u003eSee all our 360° site tours\u003c\/a\u003e.\u003c\/figcaption\u003e\n\u003c\/figure\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eTested \u0026amp; Certified — worldwide\u003c\/h2\u003e\n\u003cp\u003eAirtight White is the white-pigmented version of Passive Purple — the same liquid airtight membrane formulation — independently tested to \u003cstrong\u003eboth ASTM (ICC-ES) and EN standards\u003c\/strong\u003e, so it can be specified worldwide:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e🌿 \u003cstrong\u003eFrench A+ indoor-air rating \u0026amp; Finnish M1 class\u003c\/strong\u003e — very low VOC emissions (EN 16516 \/ RTS)\u003c\/li\u003e\n\u003cli\u003e🏠 \u003cstrong\u003ePassive House Institute Class A airtight\u003c\/strong\u003e — 0.02 m³\/h·m² @ 50 Pa (EN 12114)\u003c\/li\u003e\n\u003cli\u003e🔒 \u003cstrong\u003eAir barrier material\u003c\/strong\u003e — 0.02 L\/s·m² at 75 Pa (ASTM E2178)\u003c\/li\u003e\n\u003cli\u003e🔥 \u003cstrong\u003eReaction to fire\u003c\/strong\u003e — Class A to ASTM E84 (Flame Spread 0); Euroclass C-s1,d0 to EN 13501-1 (B-s1,d0 with FRED)\u003c\/li\u003e\n\u003cli\u003e💧 \u003cstrong\u003eWatertight\u003c\/strong\u003e (EN 14891) \u0026amp; intelligent vapour control, Sd ~0.8–40 m (EN ISO 12572)\u003c\/li\u003e\n\u003cli\u003e☀️ \u003cstrong\u003eHigh solar reflectance\u003c\/strong\u003e — the white finish reflects even more solar energy (the purple grade is independently rated SRI 52, ASTM E1980)\u003c\/li\u003e\n\u003cli\u003e🛡️ \u003cstrong\u003eRadon barrier\u003c\/strong\u003e — diffusion coefficient 3.3 × 10⁻¹² m²\/s (ISO\/TS 11665-13)\u003c\/li\u003e\n\u003cli\u003e💨 \u003cstrong\u003eMethane \/ ground-gas barrier\u003c\/strong\u003e — low permeability (ISO 15105)\u003c\/li\u003e\n\u003cli\u003e🧱 \u003cstrong\u003eStrong adhesion\u003c\/strong\u003e — steel 2.7, CLT 1.83, gypsum 1.6, brick 1.5 N\/mm² (EN ISO 4624)\u003c\/li\u003e\n\u003cli\u003e🧵 \u003cstrong\u003eFlexible \u0026amp; crack-bridging\u003c\/strong\u003e — ~219–350% elongation (EN 12311-1)\u003c\/li\u003e\n\u003cli\u003e🦠 \u003cstrong\u003e10\/10 mould resistance\u003c\/strong\u003e — no defacement (ASTM D3273)\u003c\/li\u003e\n\u003cli\u003e♻️ \u003cstrong\u003eEnvironmental Product Declaration\u003c\/strong\u003e (EN 15804)\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eICC-ES ESR-4715\u003c\/strong\u003e, Passivhaus certified \u0026amp; BBA approved\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/passive-purple-tested-certified\" title=\"Passive Purple \u0026amp; Airtight White Tested \u0026amp; Certified\"\u003eSee all test data \u0026amp; certifications →\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/pages\/passive-purple-tested-certified\" title=\"Tested \u0026amp; Certified\"\u003ePassive Purple \u0026amp; Airtight White: Tested \u0026amp; Certified (ASTM \u0026amp; EN data)\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/passive-purple-french-a-plus-emissions-rating\" title=\"French A+ rating\"\u003eThe French A+ indoor-air rating explained\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/what-is-a-vapour-control-layer-vcl-explained\" title=\"What Is a Vapour Control Layer? | VCL Explained\"\u003eWhat Is a Vapour Control Layer? | VCL Explained\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/builder-forgot-the-vapour-control-layer-how-to-fix-it\" title=\"My Builder Forgot the Vapour Control Layer? Here’s How to Fix It\"\u003eMy Builder Forgot the Vapour Control Layer? Here’s How to Fix It\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/case-study\/reuben-college-oxford-award-winning-airtight-basement-solution-using-airtight-white\" title=\"Reuben College, Oxford\"\u003eReuben College, Oxford – Award-Winning Airtight Basement with Airtight White\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\u003cp\u003e\u003cstrong\u003eQuality assurance:\u003c\/strong\u003e \u003ca href=\"\/pages\/qa-sign-off-downloads\"\u003eDownload the free Installation \u0026amp; QA Record sign-off sheet (IM-QA-03)\u003c\/a\u003e for this product.\u003c\/p\u003e","brand":"Intelligent Membranes","offers":[{"title":"Default Title","offer_id":52608799965524,"sku":"IM\/00ATW11.4","price":99.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Airtight-White.png?v=1784733345"},{"product_id":"white-airtight-vapour-control-paint-6-9kg","title":"Airtight White Brush - Home Pack (6.9kg) - Vapour Control Paint - Brush Applied","description":"\u003cp\u003e\u003cstrong\u003ePassive Purple Airtight White Brush\u003c\/strong\u003e is a \u003cstrong\u003efibre-reinforced polymer emulsion\u003c\/strong\u003e applied by paintbrush to create a \u003cstrong\u003epermanent liquid airtight vapour control membrane\u003c\/strong\u003e. Its smooth white finish makes it perfect for \u003cstrong\u003eretrofits, detailing, and projects where the airtight layer is left exposed\u003c\/strong\u003e.\u003c\/p\u003e\n\u003ch2\u003eKey Features \u0026amp; Benefits\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e✅ \u003cstrong\u003eBBA Certified \u0026amp; Passivhaus Certified\u003c\/strong\u003e – guaranteed airtightness and durability you can trust\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eM1 Class, VOC-Free\u003c\/strong\u003e – water-based, non-toxic, and safe for installers and the environment\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eFire Class C Rated\u003c\/strong\u003e – safer than traditional membranes rated only Class E\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eExceptional Airtightness\u003c\/strong\u003e – achieves \u003cstrong\u003e0.03 ACH\u003c\/strong\u003e, far beyond the Passivhaus requirement of 0.6 ACH\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eUniversal Adhesion\u003c\/strong\u003e – bonds to concrete, brick, timber, plasterboard, OSB, steel, and more\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eCoverage Efficiency\u003c\/strong\u003e – \u003cstrong\u003e1kg covers 1m²\u003c\/strong\u003e; one operative can apply up to \u003cstrong\u003e300m² per day\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eWhere to Use Airtight White Brush\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eFloor, wall, and ceiling junctions\u003c\/li\u003e\n\u003cli\u003eWindow and door reveals\u003c\/li\u003e\n\u003cli\u003eService penetrations (pipes, ducts, cables)\u003c\/li\u003e\n\u003cli\u003eSmall retrofit airtightness projects\u003c\/li\u003e\n\u003cli\u003eAny area where a \u003cstrong\u003ewhite airtight coating is required on show\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e👉 The \u003cstrong\u003e6.9kg Passive Purple Airtight White Brush\u003c\/strong\u003e is the \u003cstrong\u003efast, certified solution\u003c\/strong\u003e for creating airtight, durable, and visually clean airtight layers in both new builds and retrofit projects.\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eTested \u0026amp; Certified — worldwide\u003c\/h2\u003e\n\u003cp\u003eAirtight White Brush is the white-pigmented Passive Purple formulation — independently verified to \u003cstrong\u003eboth ASTM (ICC-ES) and EN standards\u003c\/strong\u003e:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e🌿 \u003cstrong\u003eFrench A+ indoor-air rating \u0026amp; Finnish M1 class\u003c\/strong\u003e — very low VOC emissions (EN 16516 \/ RTS)\u003c\/li\u003e\n\u003cli\u003e🏠 \u003cstrong\u003ePassive House Institute Class A airtight\u003c\/strong\u003e — 0.02 m³\/h·m² @ 50 Pa (EN 12114)\u003c\/li\u003e\n\u003cli\u003e🔒 \u003cstrong\u003eAir barrier material\u003c\/strong\u003e — 0.02 L\/s·m² at 75 Pa (ASTM E2178 · ICC-ES ESR-4715)\u003c\/li\u003e\n\u003cli\u003e🔥 \u003cstrong\u003eReaction to fire\u003c\/strong\u003e — Class A to ASTM E84; Euroclass C-s1,d0 to EN 13501-1 (B-s1,d0 with FRED)\u003c\/li\u003e\n\u003cli\u003e💧 \u003cstrong\u003eWatertight\u003c\/strong\u003e (EN 14891) \u0026amp; intelligent vapour control, Sd ~0.8–40 m (EN ISO 12572)\u003c\/li\u003e\n\u003cli\u003e🧱 \u003cstrong\u003eStrong adhesion\u003c\/strong\u003e — steel 2.7, CLT 1.83, gypsum 1.6, brick 1.5 N\/mm² (EN ISO 4624)\u003c\/li\u003e\n\u003cli\u003e🦠 \u003cstrong\u003e10\/10 mould resistance\u003c\/strong\u003e (ASTM D3273) · 🛡️ radon \u0026amp; methane barrier · ♻️ EPD (EN 15804)\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eICC-ES ESR-4715\u003c\/strong\u003e, Passivhaus certified \u0026amp; BBA approved\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/passive-purple-tested-certified\" title=\"Passive Purple Tested \u0026amp; Certified\"\u003eSee all test data \u0026amp; certifications →\u003c\/a\u003e · \u003ca href=\"\/blogs\/educational\/passive-purple-french-a-plus-emissions-rating\"\u003ethe French A+ rating explained\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/what-is-a-vapour-control-layer-vcl-explained\" title=\"What Is a Vapour Control Layer? | VCL Explained\"\u003eWhat Is a Vapour Control Layer? | VCL Explained\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/builder-forgot-the-vapour-control-layer-how-to-fix-it\" title=\"My Builder Forgot the Vapour Control Layer? Here’s How to Fix It\"\u003eMy Builder Forgot the Vapour Control Layer? Here’s How to Fix It\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/how-to-retrofit-vapour-control-without-the-mess-bba-approved-passivhaus-certified-building-control-ready\" title=\"How to Retrofit Vapour Control Without the Mess\"\u003eHow to Retrofit Vapour Control Without the Mess\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\u003cp\u003e\u003cstrong\u003eQuality assurance:\u003c\/strong\u003e \u003ca href=\"\/pages\/qa-sign-off-downloads\"\u003eDownload the free Installation \u0026amp; QA Record sign-off sheet (IM-QA-04)\u003c\/a\u003e for this product.\u003c\/p\u003e","brand":"Intelligent Membranes","offers":[{"title":"Default Title","offer_id":52608800129364,"sku":"IM\/00ATWB6.9","price":59.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Airtight-White-Brush_0f2adf53-4d8d-4abe-ace4-1ccb754800c0.png?v=1784733387"},{"product_id":"white-airtight-vapour-control-paint-5kg-brush-bundle","title":"Airtight White Brush Pack","description":"\u003cstrong\u003eProduct Collection: \u003c\/strong\u003ePassive Purple Edition\r\n\u003cstrong\u003eApplied By:\u003c\/strong\u003e Brush\r\n\u003cstrong\u003eColour:\u003c\/strong\u003e White\r\n\u003cstrong\u003eSize:\u003c\/strong\u003e 6.9kg\r\n\r\nPassive Purple Edition - Airtight White brush – High technology, fibre reinforced polymer emulsion applied with a paintbrush. Dries to form a permanent vapour control membrane.\r\n\r\n\u003cstrong\u003eBrush Applied.\u003c\/strong\u003e\r\n\r\n\u003cstrong\u003eKey Points:\u003c\/strong\u003e\r\n\u003cul\u003e\r\n \t\u003cli\u003eBBA certified\u003c\/li\u003e\r\n \t\u003cli\u003eM1 class, VOC free (volatile organic compound)\u003c\/li\u003e\r\n \t\u003cli\u003eRadon barrier\u003c\/li\u003e\r\n \t\u003cli\u003eFire class C\u003c\/li\u003e\r\n \t\u003cli\u003eUp to 300m2 a day per operative\u003c\/li\u003e\r\n \t\u003cli\u003e0.03ach (air changes per hour)\u003c\/li\u003e\r\n \t\u003cli\u003eAdheres to any substrate\u003c\/li\u003e\r\n \t\u003cli\u003e1kg will cover 1m2\u003c\/li\u003e\r\n\u003c\/ul\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/what-is-a-vapour-control-layer-vcl-explained\" title=\"What Is a Vapour Control Layer? | VCL Explained\"\u003eWhat Is a Vapour Control Layer? | VCL Explained\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/builder-forgot-the-vapour-control-layer-how-to-fix-it\" title=\"My Builder Forgot the Vapour Control Layer? Here’s How to Fix It\"\u003eMy Builder Forgot the Vapour Control Layer? Here’s How to Fix It\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/how-to-retrofit-vapour-control-without-the-mess-bba-approved-passivhaus-certified-building-control-ready\" title=\"How to Retrofit Vapour Control Without the Mess\"\u003eHow to Retrofit Vapour Control Without the Mess\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Intelligent Membranes","offers":[{"title":"Default Title","offer_id":52608800162132,"sku":"IM\/00ATWBRB","price":64.98,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Airtight-White-External-Brush-Bundle.png?v=1758025948"},{"product_id":"foil-applicator-gun","title":"Foil Applicator Gun","description":"\u003cp\u003eThe \u003cstrong\u003eFoil Applicator Gun\u003c\/strong\u003e is the professional tool for fast, precise application of IM airtight tapes and foil membranes — helping you achieve clean, well-sealed junctions and reliable airtightness every time.\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/why-im-fleece-airtight-tape-is-the-best-choice-for-retrofit-airtightness-window-sealing-and-passivhaus-projects\" title=\"Why IM Fleece Airtight Tape is the Best Choice for Airtightness\"\u003eWhy IM Fleece Airtight Tape is the Best Choice for Airtightness\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/builder-forgot-the-vapour-control-layer-how-to-fix-it\" title=\"My Builder Forgot the Vapour Control Layer? Here’s How to Fix It\"\u003eMy Builder Forgot the Vapour Control Layer? Here’s How to Fix It\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Intelligent Membranes","offers":[{"title":"Default Title","offer_id":52608800850260,"sku":"IM\/00FAG","price":28.8,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Foil-applicator-gun.jpg?v=1784733671"},{"product_id":"joist-end-bundle","title":"Joist End Bundle","description":"\u003cp\u003eThe \u003cstrong\u003eJoist End Bundle\u003c\/strong\u003e provides the airtight sealing products needed to seal joist ends and floor-to-wall junctions — common weak points for uncontrolled air leakage. Together they help you create a continuous airtight seal on timber frame and masonry builds.\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/builder-forgot-the-vapour-control-layer-how-to-fix-it\" title=\"My Builder Forgot the Vapour Control Layer? Here’s How to Fix It\"\u003eMy Builder Forgot the Vapour Control Layer? Here’s How to Fix It\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/what-is-a-vapour-control-layer-vcl-explained\" title=\"What Is a Vapour Control Layer? | VCL Explained\"\u003eWhat Is a Vapour Control Layer? | VCL Explained\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/what-is-airtightness-and-why-it-matters-for-net-zero-buildings\" title=\"What is Airtightness (and Why It Matters for Net Zero Buildings)\"\u003eWhat is Airtightness (and Why It Matters for Net Zero Buildings)\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Intelligent Membranes","offers":[{"title":"Default Title","offer_id":52608801177940,"sku":"IM\/00JEB","price":172.8,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Passive-Purple-Sealant-Foil-Applicator-1.png?v=1784733698"},{"product_id":"passive-purple-internal-airtight-vapour-control-paint-11-4kg","title":"Passive Purple - Vapour Control, Airtight \u0026 Smoke Tight Paint  (11.4kg) - Spray \/ Roller Applied","description":"\u003cpicture\u003e\u003csource media=\"(max-width:749px)\" srcset=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/new_passive_purple_product_hero_mobile_2.png?v=1784621723\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/new_passive_purple_product_hero_desktop_1.png?v=1784621723\" alt=\"Passive Purple liquid-applied airtight, vapour control and smoke tight membrane — Passivhaus certified, BBA approved and tested to ASTM and EN standards\" loading=\"eager\" style=\"width:100%;height:auto;display:block;border-radius:10px;margin:0 0 24px;\"\u003e\u003c\/picture\u003e\n\u003ch2\u003eWhat is Passive Purple and How Does it Work?\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003ePassive Purple\u003c\/strong\u003e is the world’s first \u003cstrong\u003ePassivhaus-certified liquid vapour control, airtight, and smoke tight paint\u003c\/strong\u003e – a high-performance vapour-control membrane that creates a \u003cstrong\u003econtinuous vapour control, airtight, and smoke tight layer\u003c\/strong\u003e across the building envelope. Unlike tapes, foils, or traditional membranes, Passive Purple is \u003cstrong\u003espray or roller applied\u003c\/strong\u003e, forming a seamless coating that seals even the most complex details.\u003c\/p\u003e\n\u003cp\u003eApplied to the \u003cstrong\u003ewarm side of insulation\u003c\/strong\u003e, Passive Purple prevents unwanted air leakage through walls, floors, roofs, and junctions. It is suitable for both \u003cstrong\u003enew builds\u003c\/strong\u003e and \u003cstrong\u003eretrofit airtightness projects\u003c\/strong\u003e, helping achieve strict UK airtightness standards and Passivhaus performance levels.\u003c\/p\u003e\n\u003ch2\u003eWhy Liquid Airtight Paint?\u003c\/h2\u003e\n\u003cp\u003eAir leakage is one of the biggest causes of \u003cstrong\u003eheat loss, condensation, and mould\u003c\/strong\u003e in buildings. Different materials such as brick, timber, steel, and concrete expand and contract at different rates, creating micro-cracks in plaster and finishing layers. These cracks become hidden leakage points that compromise airtightness tests and waste energy.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eLiquid airtight paint solves this problem.\u003c\/strong\u003e By coating surfaces with Passive Purple, you achieve a \u003cstrong\u003eflexible, durable airtight layer\u003c\/strong\u003e that adapts to movement in the building fabric, ensuring long-term protection against draughts and damp.\u003c\/p\u003e\n\u003ch2\u003eSpray \/ Roller or Brush Application\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpray application:\u003c\/strong\u003e Using an airless machine or roller, one installer can apply up to \u003cstrong\u003e300m² per day\u003c\/strong\u003e, making it one of the fastest airtightness solutions available.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca rel=\"noopener\" title=\"paint on airtight vapour control\" href=\"https:\/\/intelligentmembranes.com\/products\/passive-purple-internal-airtight-vapour-control-paint-6-9\" target=\"_blank\"\u003e\u003cstrong\u003eBrush application (Passive Purple Brush)\u003c\/strong\u003e\u003c\/a\u003e - A fibre-reinforced version, ideal for sealing junctions, penetrations, cracks (2-5mm), and smaller projects such as houses and retrofits\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eTogether, the spray and brush systems create a \u003cstrong\u003ecomplete airtight solution\u003c\/strong\u003e – from large surface areas to the smallest details.\u003c\/p\u003e\n\u003ch2\u003eSuitability of Passive Purple\u003c\/h2\u003e\n\u003cp\u003ePassive Purple is suitable for all types of building construction - New builds, Retrofits, Traditional build, Light Gauge Steel (LGS)\u003c\/p\u003e\n\u003ch2\u003eThe Benefits of Passive Purple\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e✅ \u003cstrong\u003ePassivhaus certified\u003c\/strong\u003e for guaranteed performance\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eSeamless and flexible\u003c\/strong\u003e – no weak points or overlaps\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eRetrofit ready\u003c\/strong\u003e – apply internally without removing walls\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eWater-based and low VOC\u003c\/strong\u003e, safe for indoor use\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eWorks on all substrates\u003c\/strong\u003e – brick, block, timber, concrete, plasterboard, OSB, and steel\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003ePermanent airtight layer\u003c\/strong\u003e – can be plastered, rendered, or painted once cured\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eAirtightness, Explained\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eWhat is airtightness?\u003c\/strong\u003e Controlling unintended air leakage through the building fabric.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHow do you achieve airtightness?\u003c\/strong\u003e By creating a continuous airtight barrier, best achieved with liquid airtight membranes.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWhat are the airtightness standards in the UK?\u003c\/strong\u003e New builds must achieve ≤10 m³\/h·m² @ 50 Pa, while Passivhaus requires ≤0.6 ACH.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWhy does airtightness matter?\u003c\/strong\u003e It reduces energy loss, improves comfort, prevents condensation, and supports a healthy indoor climate.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003ePassive Purple and Passivhaus\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eWhat is Passivhaus?\u003c\/strong\u003e A building standard focused on extreme energy efficiency and occupant comfort. \u003ca href=\"https:\/\/intelligentmembranes.com\/pages\/360-images\" target=\"_blank\" title=\"360 images of liquid applied airtight vapour control \" rel=\"noopener\"\u003eCheck out the 360 images \u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe five principles of Passivhaus:\u003c\/strong\u003e Airtightness, insulation, high-performance glazing, thermal bridge-free design, and ventilation with heat recovery.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCan it go on Retrofit Projects?\u003c\/strong\u003e Yes it can , \u003ca rel=\"noopener\" title=\"Retrofit airtightness\" href=\"https:\/\/intelligentmembranes.com\/blogs\/case-study\/airtight-membranes-on-brickwork-seamless-retrofit-sealing-with-passive-purple\" target=\"_blank\"\u003echeck out the case studies \u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u003ca rel=\"noopener\" title=\"examples of smoke tight and airtight liquid vapour controls\" href=\"https:\/\/intelligentmembranes.com\/pages\/blogs\" target=\"_blank\"\u003eExamples of Passivhaus projects\u003c\/a\u003e:\u003c\/strong\u003e Thousands across Europe and the UK now use liquid airtight membranes like Passive Purple to achieve certification.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003ePreparation \u0026amp; Priming\u003c\/h2\u003e\n\u003cp\u003eGreat airtightness starts with the right prep. On bare, dusty, porous or lime substrates, prime first with \u003ca href=\"\/products\/lime-prime-10kg\" title=\"Lime Prime\"\u003eLime Prime\u003c\/a\u003e; on dense, sealed or older substrates that need consolidating, use \u003ca href=\"\/products\/render-primer-im\" title=\"Primer I.M\"\u003ePrimer I.M\u003c\/a\u003e. Once Passive Purple has cured, prime it with \u003ca href=\"\/products\/supergrip-primer-10kg\" title=\"Supergrip primer\"\u003eSupergrip\u003c\/a\u003e so plaster and dot-and-dab bond firmly. Right primer, reliable bond.\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eTested \u0026amp; Certified — worldwide\u003c\/h2\u003e\n\u003cp\u003ePassive Purple is verified to \u003cstrong\u003eboth ASTM (ICC-ES) and EN standards\u003c\/strong\u003e, making it suitable for projects worldwide:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e🌿 \u003cstrong\u003eFrench A+ indoor-air rating \u0026amp; Finnish M1 class\u003c\/strong\u003e — very low VOC emissions (EN 16516 \/ RTS)\u003c\/li\u003e\n\u003cli\u003e🏠 \u003cstrong\u003ePassive House Institute Class A airtight\u003c\/strong\u003e — 0.02 m³\/h·m² @ 50 Pa (EN 12114)\u003c\/li\u003e\n\u003cli\u003e🔒 \u003cstrong\u003eAir barrier material\u003c\/strong\u003e — 0.02 L\/s·m² at 75 Pa (ASTM E2178)\u003c\/li\u003e\n\u003cli\u003e🔥 \u003cstrong\u003eReaction to fire\u003c\/strong\u003e — Class A to ASTM E84 (Flame Spread 0); Euroclass C-s1,d0 to EN 13501-1 (B-s1,d0 with FRED)\u003c\/li\u003e\n\u003cli\u003e💧 \u003cstrong\u003eWatertight\u003c\/strong\u003e (EN 14891) \u0026amp; intelligent vapour control, Sd ~0.8–40 m (EN ISO 12572)\u003c\/li\u003e\n\u003cli\u003e☀️ \u003cstrong\u003eSolar Reflectance Index 52\u003c\/strong\u003e — reflects ~45% of solar energy (ASTM E1980)\u003c\/li\u003e\n\u003cli\u003e🛡️ \u003cstrong\u003eRadon barrier\u003c\/strong\u003e — diffusion coefficient 3.3 × 10⁻¹² m²\/s (ISO\/TS 11665-13)\u003c\/li\u003e\n\u003cli\u003e💨 \u003cstrong\u003eMethane \/ ground-gas barrier\u003c\/strong\u003e — low permeability (ISO 15105)\u003c\/li\u003e\n\u003cli\u003e🧱 \u003cstrong\u003eStrong adhesion\u003c\/strong\u003e — steel 2.7, CLT 1.83, gypsum 1.6, brick 1.5 N\/mm² (EN ISO 4624)\u003c\/li\u003e\n\u003cli\u003e🧵 \u003cstrong\u003eFlexible \u0026amp; crack-bridging\u003c\/strong\u003e — ~219–350% elongation (EN 12311-1)\u003c\/li\u003e\n\u003cli\u003e🦠 \u003cstrong\u003e10\/10 mould resistance\u003c\/strong\u003e — no defacement (ASTM D3273)\u003c\/li\u003e\n\u003cli\u003e♻️ \u003cstrong\u003eEnvironmental Product Declaration\u003c\/strong\u003e (EN 15804)\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eICC-ES ESR-4715\u003c\/strong\u003e, Passivhaus certified \u0026amp; BBA approved\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/passive-purple-tested-certified\" title=\"Passive Purple Tested \u0026amp; Certified\"\u003eSee all test data \u0026amp; certifications →\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003e🇺🇸 \u003cstrong\u003eUS projects:\u003c\/strong\u003e tested to ASTM standards for world markets — \u003ca href=\"\/pages\/us-specifications\" title=\"US specifications in CSI MasterFormat\"\u003edownload the US specifications (CSI MasterFormat)\u003c\/a\u003e or order through \u003ca href=\"\/pages\/chicago\" title=\"Passive Purple Chicago — distributed and installed by WickRight\"\u003eWickRight, our Chicago distribution \u0026amp; installation partner\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eWant to understand airtightness and vapour control before you buy? These guides explain how Passive Purple is used on real projects:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/pages\/passive-purple-tested-certified\" title=\"Passive Purple Tested \u0026amp; Certified\"\u003ePassive Purple: Tested \u0026amp; Certified (ICC-ES, ASTM \u0026amp; EN data)\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/passive-purple-class-a-airtight-passive-house-institute\" title=\"Passive House Class A airtight\"\u003ePassive House Institute Class A airtight (EN 12114)\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/passive-purple-french-a-plus-emissions-rating\" title=\"French A+ rating\"\u003ePassive Purple: the French A+ indoor-air rating\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/pages\/liquid-airtight-membranes-vs-parge-coating\" title=\"Liquid Airtight Membranes vs Parge Coating\"\u003eLiquid Airtight Membranes vs Parge Coating\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/what-is-a-vapour-control-layer-vcl-explained\" title=\"What Is a Vapour Control Layer? VCL Explained\"\u003eWhat Is a Vapour Control Layer? | VCL Explained\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\u003cp\u003e\u003cstrong\u003eQuality assurance:\u003c\/strong\u003e \u003ca href=\"\/pages\/qa-sign-off-downloads\"\u003eDownload the free Installation \u0026amp; QA Record sign-off sheet (IM-QA-01)\u003c\/a\u003e for this product.\u003c\/p\u003e\u003ch2\u003eConnect the membrane at windows and junctions\u003c\/h2\u003e\u003cp\u003ePlan the adjoining tape detail as well as the coated area. Our \u003ca href=\"\/blogs\/educational\/airtightness-tape-guide\"\u003eairtightness tape guide\u003c\/a\u003e covers width and substrate selection, while \u003ca href=\"\/blogs\/educational\/airtightness-tape-vs-liquid-airtight-membrane\"\u003etape versus liquid membrane\u003c\/a\u003e explains compatible interfaces, preparation and inspection. Use the specified coating-to-tape detail and check continuity before covering.\u003c\/p\u003e","brand":"Intelligent Membranes","offers":[{"title":"Default Title","offer_id":52608801341780,"sku":"IM\/00PPS11.4","price":99.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Passive_Purple.png?v=1784732952"},{"product_id":"passive-purple-internal-airtight-vapour-control-paint-6-9","title":"Passive Purple Brush Home Pack 6.9kg - Airtight Paint","description":"\u003ch2\u003eWhat is Passive Purple Brush?\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003ePassive Purple Brush\u003c\/strong\u003e is a \u003cstrong\u003efibre-reinforced, liquid-applied airtight membrane\u003c\/strong\u003e designed for detailed airtightness work. Applied with a simple paintbrush, it creates a \u003cstrong\u003epermanent, seamless vapour-control layer\u003c\/strong\u003e that seals tricky gaps and penetrations where spraying or rolling is difficult.\u003c\/p\u003e\n\u003ch3\u003eWhere is it used?\u003c\/h3\u003e\n\u003cp\u003ePassive Purple Brush is ideal for:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eService penetrations\u003c\/strong\u003e (pipes, cables, ducts)\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eWindow and door frames\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eFloor-to-wall and wall-to-ceiling junctions\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eCracks and gaps up to 5mm\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTouch-ups after air testing\u003c\/strong\u003e or snagging\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eWhy use the Brush version?\u003c\/h3\u003e\n\u003cp\u003eUnlike spray-applied Passive Purple, the \u003cstrong\u003eBrush version contains fibres\u003c\/strong\u003e that span and seal larger cracks and irregularities. This makes it the go-to airtight paint for precision work, detailing, and repairs, while still delivering the same \u003cstrong\u003ePassivhaus-certified airtightness\u003c\/strong\u003e as the main system.\u003c\/p\u003e\n\u003ch3\u003eSurface preparation\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eEnsure surfaces are \u003cstrong\u003esolid, dust-free, and closed\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLarge gaps (\u0026gt;5mm):\u003c\/strong\u003e Fill with cement-based filler or foam before application.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSmall to medium gaps (2–5mm):\u003c\/strong\u003e Passive Purple Brush can be applied directly.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eApplication \u0026amp; coverage\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eApplied with a \u003cstrong\u003eflat paintbrush\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003eEasy to use for small projects and detailed work.\u003c\/li\u003e\n\u003cli\u003eOnce cured, it can be \u003cstrong\u003epainted, plastered, or rendered over\u003c\/strong\u003e.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eWhy airtightness matters\u003c\/h3\u003e\n\u003cp\u003eAir leakage through cracks and junctions:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eReduces energy efficiency\u003c\/li\u003e\n\u003cli\u003eAllows draughts, damp, and mould\u003c\/li\u003e\n\u003cli\u003eCan compromise Passivhaus and building regulations compliance\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eBy sealing with Passive Purple Brush, you ensure every junction is airtight, securing energy performance and long-term building health.\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eTested \u0026amp; Certified\u003c\/h2\u003e\n\u003cp\u003ePassive Purple Brush is covered by the same independent testing and ICC-ES evaluation (ESR-4715) as the Passive Purple system:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e🌿 \u003cstrong\u003eFrench A+ indoor-air rating \u0026amp; Finnish M1 class\u003c\/strong\u003e — very low VOC emissions (EN 16516 \/ RTS)\u003c\/li\u003e\n\u003cli\u003e🏠 \u003cstrong\u003ePassive House Institute Class A airtight\u003c\/strong\u003e — 0.02 m³\/h·m² @ 50 Pa (EN 12114)\u003c\/li\u003e\n\u003cli\u003e🔒 \u003cstrong\u003eAir barrier material\u003c\/strong\u003e — air leakage 0.02 L\/s·m² at 75 Pa (ASTM E2178)\u003c\/li\u003e\n\u003cli\u003e🔥 \u003cstrong\u003eReaction to fire\u003c\/strong\u003e — Class A to ASTM E84 (Flame Spread 0, Smoke 35); Euroclass C-s1,d0 to EN 13501-1 (B-s1,d0 with FRED)\u003c\/li\u003e\n\u003cli\u003e💧 \u003cstrong\u003eWatertight\u003c\/strong\u003e (EN 14891) \u0026amp; intelligent vapour control (EN ISO 12572)\u003c\/li\u003e\n\u003cli\u003e🧱 \u003cstrong\u003eStrong adhesion\u003c\/strong\u003e across substrates (EN ISO 4624) \u0026amp; \u003cstrong\u003e10\/10 mould resistance\u003c\/strong\u003e (ASTM D3273)\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eICC-ES ESR-4715\u003c\/strong\u003e, Passivhaus certified \u0026amp; BBA approved\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eSee the full \u003ca href=\"\/pages\/passive-purple-tested-certified\" title=\"Passive Purple Tested \u0026amp; Certified\"\u003etest data \u0026amp; certifications\u003c\/a\u003e, or read how Passive Purple delivers \u003ca href=\"\/blogs\/educational\/passive-purple-cool-roof-solar-reflectance-sri-52\" title=\"Passive Purple Solar-Reflective Performance (SRI 52)\"\u003esolar-reflective performance (SRI 52)\u003c\/a\u003e.\u003c\/p\u003e\n\u003cp\u003e🇺🇸 \u003cstrong\u003eUS projects:\u003c\/strong\u003e tested to ASTM standards for world markets — \u003ca href=\"\/pages\/us-specifications\" title=\"US specifications in CSI MasterFormat\"\u003edownload the US specifications (CSI MasterFormat)\u003c\/a\u003e or order through \u003ca href=\"\/pages\/chicago\" title=\"Passive Purple Chicago — distributed and installed by WickRight\"\u003eWickRight, our Chicago distribution \u0026amp; installation partner\u003c\/a\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/what-does-passive-purple-stick-to-adhesion-testing\" title=\"What does Passive Purple stick to?\"\u003eWhat Does Passive Purple Stick To? Adhesion Testing\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/builder-forgot-the-vapour-control-layer-how-to-fix-it\" title=\"My Builder Forgot the Vapour Control Layer? Here’s How to Fix It\"\u003eMy Builder Forgot the Vapour Control Layer? Here’s How to Fix It\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/what-is-a-vapour-control-layer-vcl-explained\" title=\"What Is a Vapour Control Layer? | VCL Explained\"\u003eWhat Is a Vapour Control Layer? | VCL Explained\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/the-airtightness-challenge-facing-modern-construction-why-blockwork-alone-is-no-longer-enough\" title=\"The Airtightness Challenge: Why Blockwork Alone Is No Longer Enough\"\u003eThe Airtightness Challenge: Why Blockwork Alone Is No Longer Enough\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/grand-designs-passivhaus-premium-uses-airtight-membrane\" title=\"Grand Designs Passivhaus Premium Uses Airtight Membrane\"\u003eGrand Designs Passivhaus Premium Uses Airtight Membrane\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\u003cp\u003e\u003cstrong\u003eQuality assurance:\u003c\/strong\u003e \u003ca href=\"\/pages\/qa-sign-off-downloads\"\u003eDownload the free Installation \u0026amp; QA Record sign-off sheet (IM-QA-02)\u003c\/a\u003e for this product.\u003c\/p\u003e","brand":"Intelligent Membranes","offers":[{"title":"6.9kg","offer_id":53767114850644,"sku":"IM\/00PPB6.9","price":59.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/PP-Internal-Home-Pack.png?v=1784733120"},{"product_id":"internal-airtight-vapour-control-paint-6-9kg-brush-home-pack-bundle","title":"Passive Purple Brush Pack","description":"\u003ch2\u003eWhat is Passive Purple?\u003c\/h2\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n    Passive Purple liquid airtight vapour control membrane is an airtight coating applied using an airless spray device on all areas of the external envelope (warm side of the insulation) of a building. This includes difficult connection areas such as floors, walls, roofs, and joists.\n  \u003c\/li\u003e\n\n  \u003cli\u003e\n    When Passive Purple is used on the warm side of the insulation, it can be applied to either face of the external envelope.\n  \u003c\/li\u003e\n\n  \u003cli\u003e\n    Before application, ensure the surface is solid, dust-free, and closed.\n  \u003c\/li\u003e\n\n  \u003cli\u003e\n    A closed surface means all holes and joints must be sealed beforehand:\n    \u003cul\u003e\n      \u003cli\u003e\n        \u003cstrong\u003eLarge holes and joints (\u0026gt;5mm):\u003c\/strong\u003e seal using fast-setting cement-based products or polyurethane foam.\n      \u003c\/li\u003e\n      \u003cli\u003e\n        \u003cstrong\u003eSmall holes and joints (2–5mm):\u003c\/strong\u003e seal directly using Passive Purple Liquid Brush, the thicker brush-applied version.\n      \u003c\/li\u003e\n    \u003c\/ul\u003e\n  \u003c\/li\u003e\n\n  \u003cli\u003e\n    After preparation, Passive Purple can be spray-applied with an airless machine, allowing a single operator to apply up to \u003cstrong\u003e300m² per day\u003c\/strong\u003e.\n  \u003c\/li\u003e\n\n  \u003cli\u003e\n    For smaller projects, such as private houses, Passive Purple Brush can be applied using a flat paintbrush.\n  \u003c\/li\u003e\n\n  \u003cli\u003e\n    Wall-to-ceiling connections must also be made airtight, especially where different construction materials meet, such as brick to concrete or steel to concrete.\n  \u003c\/li\u003e\n\n  \u003cli\u003e\n    Different construction materials respond differently to changes in humidity and temperature, which can cause small cracks in finishes. These cracks may lead to air leakage, reduced energy performance, and an increased risk of damp and mould.\n  \u003c\/li\u003e\n\n  \u003cli\u003e\n    Both airtight paints can be used for wall-to-ceiling connections: Passive Purple spray-applied and Passive Purple Brush.\n  \u003c\/li\u003e\n\n  \u003cli\u003e\n    Get in touch with our team at \n    \u003ca href=\"mailto:info@intelligentmembranes.com\"\u003einfo@intelligentmembranes.com\u003c\/a\u003e \n    to learn more about Passive Purple and airtightness solutions.\n  \u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e\n  \u003cstrong\u003eNote:\u003c\/strong\u003e If you do not have an airless sprayer but still wish to install Passive Purple yourself, a roller-applied version is also available. While application may take a little longer, it delivers the same reliable airtight performance.\n\u003c\/p\u003e\n\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/builder-forgot-the-vapour-control-layer-how-to-fix-it\" title=\"My Builder Forgot the Vapour Control Layer? Here’s How to Fix It\"\u003eMy Builder Forgot the Vapour Control Layer? Here’s How to Fix It\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/what-is-a-vapour-control-layer-vcl-explained\" title=\"What Is a Vapour Control Layer? | VCL Explained\"\u003eWhat Is a Vapour Control Layer? | VCL Explained\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/how-to-retrofit-vapour-control-without-the-mess-bba-approved-passivhaus-certified-building-control-ready\" title=\"How to Retrofit Vapour Control Without the Mess\"\u003eHow to Retrofit Vapour Control Without the Mess\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Intelligent Membranes","offers":[{"title":"Default Title","offer_id":52608801505620,"sku":"IM\/00PPBRB","price":64.98,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Home-Pack-2.png?v=1784732991"},{"product_id":"facade-waterproofing-membrane-5kg","title":"Passive Purple External Airtight Fire Rated Façade Waterproofing Membrane (5kg) - Purple Brush","description":"\u003cp\u003e\u003cspan data-teams=\"true\"\u003ePassive Purple External Brush, specifically designed to seal joints and gaps with precision and durability. This advanced liquid-applied weather barrier is perfect for external applications where airtightness and weather protection are critical. The brush version contains specialised fibres, allowing it to span larger gaps and joints, delivering exceptional coverage and performance in challenging areas.\u003c\/span\u003e\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eTested \u0026amp; Certified — fire-rated, watertight \u0026amp; breathable\u003c\/h2\u003e\n\u003cp\u003eIndependently certified to both European (EN) and US (ASTM) standards:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e🔥 \u003cstrong\u003eReaction to fire Euroclass B-s1,d0\u003c\/strong\u003e (EN 13501-1, on A1 substrates ≥653 kg\/m³) \u0026amp; \u003cstrong\u003eASTM E84 Class A\u003c\/strong\u003e (Flame Spread 0 \/ Smoke 15)\u003c\/li\u003e\n\u003cli\u003e💧 \u003cstrong\u003eWatertight Class W1\u003c\/strong\u003e (EN 13859-2) \u0026amp; water permeability Class W3 (EN 1062-3); near-zero water absorption (EN 16302)\u003c\/li\u003e\n\u003cli\u003e🌬️ \u003cstrong\u003eBreathable \/ vapour-open\u003c\/strong\u003e — Sd ≈ 0.6 m (EN ISO 12572)\u003c\/li\u003e\n\u003cli\u003e🧱 \u003cstrong\u003eCrack-bridging\u003c\/strong\u003e A3 (23°C) \/ A4 (-10°C) (EN 1062-7) \u0026amp; CO₂ \/ carbonation barrier Class C1 (EN 1062-6)\u003c\/li\u003e\n\u003cli\u003e☀️ \u003cstrong\u003eUV-stable\u003c\/strong\u003e (strength increases after 500 h UV) · low-emission \u003cstrong\u003eEMICODE EC2\u003c\/strong\u003e · anti-fungus (rating 0)\u003c\/li\u003e\n\u003cli\u003e🇬🇧 \u003cstrong\u003eKiwa BDA Agrément\u003c\/strong\u003e (BAW-21-214-P-A-UK) · Passive House component (phB) · US ICC-ES AC212 water-resistive barrier\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/passive-purple-tested-certified\" title=\"Tested \u0026amp; Certified\"\u003eSee all test data \u0026amp; certifications →\u003c\/a\u003e · read about \u003ca href=\"\/blogs\/educational\/passive-purple-external-fire-class-b-watertight-breathable\"\u003ePassive Purple External\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/airtight-and-vapour-control-for-high-rise-re-cladding-installed-from-the-outside-i\" title=\"Airtight and Vapour Control for High-Rise Re-Cladding\"\u003eAirtight and Vapour Control for High-Rise Re-Cladding\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/what-is-airtightness-and-why-it-matters-for-net-zero-buildings\" title=\"What is Airtightness (and Why It Matters for Net Zero Buildings)\"\u003eWhat is Airtightness (and Why It Matters for Net Zero Buildings)\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/damp-walls-two-breathable-solutions-that-actually-work\" title=\"Damp Walls? Two Breathable Solutions That Actually Work\"\u003eDamp Walls? Two Breathable Solutions That Actually Work\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\u003cp\u003e\u003cstrong\u003eQuality assurance:\u003c\/strong\u003e \u003ca href=\"\/pages\/qa-sign-off-downloads\"\u003eDownload the free Installation \u0026amp; QA Record sign-off sheet (IM-QA-05)\u003c\/a\u003e for this product.\u003c\/p\u003e","brand":"Intelligent Membranes","offers":[{"title":"Purple","offer_id":52682707665236,"sku":"IM\/00PPEB5","price":55.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Passive-Purple-External-Brush.png?v=1784733727"},{"product_id":"brush-applied-facade-waterproofing-membrane-5kg-bundle","title":"Passive Purple External Brush Pack","description":"\u003cspan lang=\"EN-GB\"\u003eExcelling characteristics of passive purple external: \u003c\/span\u003e\r\n\u003cul type=\"disc\"\u003e\r\n \t\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eFireclass B\u003c\/span\u003e\u003c\/li\u003e\r\n \t\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eRaintight but vapour breathable\u003c\/span\u003e\u003c\/li\u003e\r\n \t\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eAirtight\u003c\/span\u003e\u003c\/li\u003e\r\n \t\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eUV resistant\u003c\/span\u003e\u003c\/li\u003e\r\n \t\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eAnti fungus\u003c\/span\u003e\u003c\/li\u003e\r\n \t\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eSelfcleaning \/ reduced dirt pickup caused by UV netting\u003c\/span\u003e\u003c\/li\u003e\r\n \t\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eCrackbridging\u003c\/span\u003e\u003c\/li\u003e\r\n \t\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eCarbonatation block (for concrete); realkalising (concrete)\u003c\/span\u003e\u003c\/li\u003e\r\n \t\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eProtection against salts (for roads) (concrete structures).\u003c\/span\u003e\u003c\/li\u003e\r\n \t\u003cli\u003eCan also be used a as a protective coating on concrete as antiacrbonatation on concrete \/ cementcoating.\u003c\/li\u003e\r\n \t\u003cli\u003e1kg will cover 1m2\u003c\/li\u003e\r\n\u003c\/ul\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/airtight-and-vapour-control-for-high-rise-re-cladding-installed-from-the-outside-i\" title=\"Airtight and Vapour Control for High-Rise Re-Cladding\"\u003eAirtight and Vapour Control for High-Rise Re-Cladding\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/what-is-airtightness-and-why-it-matters-for-net-zero-buildings\" title=\"What is Airtightness (and Why It Matters for Net Zero Buildings)\"\u003eWhat is Airtightness (and Why It Matters for Net Zero Buildings)\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Intelligent Membranes","offers":[{"title":"Default Title","offer_id":52608802062676,"sku":"IM\/00PPEBRB","price":64.98,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Passive-Purple-External-Brush-Pack-1.png?v=1758025978"},{"product_id":"passive-purple-external-bundle","title":"Passive Purple External Bundle","description":"\u003cp\u003eThe \u003cstrong\u003ePassive Purple External Bundle\u003c\/strong\u003e combines our Fire Class B, liquid-applied airtight and weatherproof façade membrane in one complete pack for external airtightness and weather protection. Raintight yet vapour-breathable, it is ideal for timber frame, retrofit and high-performance façade projects.\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/airtight-and-vapour-control-for-high-rise-re-cladding-installed-from-the-outside-i\" title=\"Airtight and Vapour Control for High-Rise Re-Cladding\"\u003eAirtight and Vapour Control for High-Rise Re-Cladding\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/what-is-airtightness-and-why-it-matters-for-net-zero-buildings\" title=\"What is Airtightness (and Why It Matters for Net Zero Buildings)\"\u003eWhat is Airtightness (and Why It Matters for Net Zero Buildings)\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/damp-walls-two-breathable-solutions-that-actually-work\" title=\"Damp Walls? Two Breathable Solutions That Actually Work\"\u003eDamp Walls? Two Breathable Solutions That Actually Work\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Intelligent Membranes","offers":[{"title":"Default Title","offer_id":52608802095444,"sku":"IM\/00PPEB","price":564.93,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Passive-Purple-Preperation-Pack-1.png?v=1784733180"},{"product_id":"passive-purple-preparation-pack","title":"Passive Purple Preparation Pack","description":"\u003ch2\u003eWhat is and how to use Passive Purple?\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003ePassive Purple Intelligent liquid airtight vapour control membrane is an airtight coating applied using an airless spray device to all areas of the external envelope (warm side of the insulation) of a building. This includes difficult connection areas such as floors, walls, roofs, and joists.\u003c\/li\u003e\n\u003cli\u003eWhen Passive Purple Intelligent Membrane is used on the warm side of the insulation, it can be applied to either face of the external envelope to create a vapour control layer.\u003c\/li\u003e\n\u003cli\u003eBefore installation, ensure the surface is solid, dust-free, and closed.\u003c\/li\u003e\n\u003cli\u003eA closed surface means all holes and joints must be sealed beforehand:\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eLarge holes and joints (\u0026gt;5mm):\u003c\/strong\u003e seal using fast-setting cement-based products or polyurethane foam.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSmall holes and joints (2–5mm):\u003c\/strong\u003e seal directly using Passive Purple Liquid Brush, the thicker brush-applied version.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003eAfter preparation, Passive Purple can be spray-applied with an airless machine, allowing a single operator to apply up to \u003cstrong\u003e300m² per day\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003eFor smaller projects, such as private houses, Passive Purple Brush can be applied using a flat paintbrush.\u003c\/li\u003e\n\u003cli\u003eWall-to-ceiling connections must also be made airtight, especially where different construction materials meet, such as brick to concrete or steel to concrete.\u003c\/li\u003e\n\u003cli\u003eDifferent construction materials respond differently to changes in humidity and temperature, which can lead to small cracks in finishes. These cracks may cause air leakage, reduced energy performance, and increase the risk of damp and mould.\u003c\/li\u003e\n\u003cli\u003eBoth airtight paints can be used for wall-to-ceiling connections: Passive Purple spray-applied and Passive Purple Brush.\u003c\/li\u003e\n\u003cli\u003eGet in touch with our team at \u003ca href=\"mailto:info@intelligentmembranes.com\"\u003einfo@intelligentmembranes.com\u003c\/a\u003e if you would like to learn more.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eNote:\u003c\/strong\u003e If you do not have an airless sprayer but still wish to install Passive Purple yourself, a roller-applied version is also available. While application may take a little longer, it still delivers reliable airtight performance.\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/builder-forgot-the-vapour-control-layer-how-to-fix-it\" title=\"My Builder Forgot the Vapour Control Layer? Here’s How to Fix It\"\u003eMy Builder Forgot the Vapour Control Layer? Here’s How to Fix It\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/what-is-a-vapour-control-layer-vcl-explained\" title=\"What Is a Vapour Control Layer? | VCL Explained\"\u003eWhat Is a Vapour Control Layer? | VCL Explained\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/how-to-retrofit-vapour-control-without-the-mess-bba-approved-passivhaus-certified-building-control-ready\" title=\"How to Retrofit Vapour Control Without the Mess\"\u003eHow to Retrofit Vapour Control Without the Mess\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Intelligent Membranes","offers":[{"title":"Default Title","offer_id":52608802128212,"sku":"IM\/00PPPP","price":213.78,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Passive-Purple-Preperation-Pack.png?v=1758025979"},{"product_id":"passive-purple-x-fire-class-b-airtight-paint-5kg","title":"Passive Purple X (5kg) Brush Applied","description":"\u003cp\u003e\u003cspan lang=\"EN-GB\"\u003eKey characteristics of Passive Purple X (shares Passive Purple External's certified performance): \u003c\/span\u003e\u003c\/p\u003e\n\u003cul type=\"disc\"\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eRaintight but vapour breathable\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eAirtight\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eUV resistant\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eAnti fungus\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eSelfcleaning \/ reduced dirt pickup caused by UV netting\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eCrackbridging\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eCarbonatation block (for concrete); realkalising (concrete)\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eProtection against salts (for roads) (concrete structures).\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003eCan also be used as a protective coating on concrete as anticarbonisatation on concrete \/ cement coating.\u003c\/li\u003e\n\u003cli\u003e1kg will cover 1m2\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv style=\"border-top: 2px solid #b5985a; margin-top: 28px; padding-top: 18px;\"\u003e\n\u003ch2 style=\"color: #4a1a6e;\"\u003eTested \u0026amp; Certified — fire-rated, watertight \u0026amp; breathable\u003c\/h2\u003e\n\u003cp\u003ePassive Purple X shares the certified Passive Purple External performance, independently verified to both European (EN) and US (ASTM) standards:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e🔥 \u003cstrong\u003eReaction to fire Euroclass B-s1,d0\u003c\/strong\u003e (EN 13501-1, on A1 substrates ≥653 kg\/m³) \u0026amp; \u003cstrong\u003eASTM E84 Class A\u003c\/strong\u003e (Flame Spread 0 \/ Smoke 15)\u003c\/li\u003e\n\u003cli\u003e💧 \u003cstrong\u003eWatertight Class W1\u003c\/strong\u003e (EN 13859-2) \u0026amp; water permeability Class W3 (EN 1062-3)\u003c\/li\u003e\n\u003cli\u003e🌬️ \u003cstrong\u003eBreathable \/ vapour-open\u003c\/strong\u003e — Sd ≈ 0.6 m (EN ISO 12572)\u003c\/li\u003e\n\u003cli\u003e🧱 \u003cstrong\u003eCrack-bridging\u003c\/strong\u003e A3 (23°C) \/ A4 (-10°C) (EN 1062-7) \u0026amp; CO₂ \/ carbonation barrier Class C1 (EN 1062-6)\u003c\/li\u003e\n\u003cli\u003e🇬🇧 \u003cstrong\u003eKiwa BDA Agrément\u003c\/strong\u003e (BAW-21-214-P-A-UK) · Passive House component (phB) · US ICC-ES AC212\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/passive-purple-tested-certified\" title=\"Tested \u0026amp; Certified\"\u003eSee all test data \u0026amp; certifications →\u003c\/a\u003e · \u003ca href=\"\/blogs\/educational\/passive-purple-external-fire-class-b-watertight-breathable\"\u003ePassive Purple External explained\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top: 2px solid #b5985a; margin-top: 28px; padding-top: 18px;\"\u003e\n\u003ch2 style=\"color: #4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/airtight-and-vapour-control-for-high-rise-re-cladding-installed-from-the-outside-i\" title=\"Airtight and Vapour Control for High-Rise Re-Cladding\"\u003eAirtight and Vapour Control for High-Rise Re-Cladding\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/the-airtightness-challenge-facing-modern-construction-why-blockwork-alone-is-no-longer-enough\" title=\"The Airtightness Challenge: Why Blockwork Alone Is No Longer Enough\"\u003eThe Airtightness Challenge: Why Blockwork Alone Is No Longer Enough\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/how-to-retrofit-vapour-control-without-the-mess-bba-approved-passivhaus-certified-building-control-ready\" title=\"How to Retrofit Vapour Control Without the Mess\"\u003eHow to Retrofit Vapour Control Without the Mess\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cp\u003e\u003cstrong\u003eQuality assurance:\u003c\/strong\u003e \u003ca href=\"\/pages\/qa-sign-off-downloads\"\u003eDownload the free Installation \u0026amp; QA Record sign-off sheet (IM-QA-06)\u003c\/a\u003e for this product.\u003c\/p\u003e","brand":"Intelligent Membranes","offers":[{"title":"Purple","offer_id":52682702258516,"sku":"IM\/00PPXB5PURPLE","price":55.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/PASSIVE-PURPLE-X-5-KG.png?v=1758025982"},{"product_id":"passivhaus-airtight-sealant","title":"Passivhaus Airtight Sealant - 600ml","description":"\u003cp\u003e\u003cstrong\u003ePassive Purple Sealant Tubes – Perfect for Airtight Sealing of Gaps in the Building Fabric\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePassive Purple\u003c\/strong\u003e brush in convenient sealant tubes is the ultimate solution for air-sealing gaps and cracks in the building fabric, ensuring airtightness and improved energy efficiency. This flexible, liquid-applied sealant is specifically formulated for quick and easy application, making it ideal for sealing joints, penetrations, and gaps in walls, floors, and ceilings. Designed to meet the highest airtightness standards, \u003cstrong\u003ePassive Purple\u003c\/strong\u003e helps reduce energy loss and is suitable for both new-build and retrofit projects.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eKey Features and Benefits:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eEfficient Airsealing:\u003c\/strong\u003e Passive Purple sealant is ideal for sealing gaps and cracks in the building envelope, creating an airtight barrier that prevents air leakage and improves thermal performance. Perfect for use around windows, doors, service penetrations, and joints.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eQuick and Easy Application:\u003c\/strong\u003e Sealant tubes allow Passive Purple to be applied directly into gaps and joints using a standard caulking gun, providing precise control and a smooth, seamless finish.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVersatile Use:\u003c\/strong\u003e Suitable for a wide range of substrates including timber, concrete, brick, and plasterboard.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDurable and Long-Lasting:\u003c\/strong\u003e Once applied, Passive Purple forms a flexible, durable seal that accommodates building movement and environmental changes while maintaining airtightness.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEnergy Efficiency:\u003c\/strong\u003e By eliminating air leaks, Passive Purple helps reduce energy loss, lowers heating and cooling costs, and supports energy-efficient, sustainable construction.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eWhy Choose Passive Purple in Sealant Tubes?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecision Application:\u003c\/strong\u003e Sealant tubes allow targeted application, ensuring even the smallest gaps are effectively sealed.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImproved Energy Performance:\u003c\/strong\u003e Sealing gaps with Passive Purple significantly reduces air infiltration, improving comfort and overall thermal performance.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePerfect for Retrofit and New Builds:\u003c\/strong\u003e Whether sealing a new building or upgrading an existing structure, Passive Purple sealant tubes offer a practical and reliable airtightness solution.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eAchieve superior airtightness with \u003cstrong\u003ePassive Purple Sealant Tubes\u003c\/strong\u003e — an easy-to-use, flexible solution for sealing gaps in the building fabric. Ideal for improving energy efficiency and sealing joints in both new and retrofit projects, \u003cstrong\u003ePassive Purple\u003c\/strong\u003e delivers a durable, long-lasting airtight seal.\u003c\/p\u003e\n\u003cp\u003eEach sausage covers approximately \u003cstrong\u003e6 linear metres\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eTested \u0026amp; Certified — worldwide\u003c\/h2\u003e\n\u003cp\u003ePassive Purple in sealant tubes is the same Passive Purple liquid airtight membrane formulation — independently verified to \u003cstrong\u003eboth ASTM (ICC-ES) and EN standards\u003c\/strong\u003e:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e🌿 \u003cstrong\u003eFrench A+ indoor-air rating \u0026amp; Finnish M1 class\u003c\/strong\u003e — very low VOC emissions (EN 16516 \/ RTS)\u003c\/li\u003e\n\u003cli\u003e🏠 \u003cstrong\u003ePassive House Institute Class A airtight\u003c\/strong\u003e — 0.02 m³\/h·m² @ 50 Pa (EN 12114)\u003c\/li\u003e\n\u003cli\u003e🔒 \u003cstrong\u003eAir barrier material\u003c\/strong\u003e — 0.02 L\/s·m² at 75 Pa (ASTM E2178 · ICC-ES ESR-4715)\u003c\/li\u003e\n\u003cli\u003e🔥 \u003cstrong\u003eReaction to fire\u003c\/strong\u003e — Class A to ASTM E84; Euroclass C-s1,d0 to EN 13501-1 (B-s1,d0 with FRED)\u003c\/li\u003e\n\u003cli\u003e💧 \u003cstrong\u003eWatertight\u003c\/strong\u003e (EN 14891) \u0026amp; intelligent vapour control, Sd ~0.8–40 m (EN ISO 12572)\u003c\/li\u003e\n\u003cli\u003e🧱 \u003cstrong\u003eStrong adhesion\u003c\/strong\u003e — steel 2.7, CLT 1.83, gypsum 1.6, brick 1.5 N\/mm² (EN ISO 4624)\u003c\/li\u003e\n\u003cli\u003e🦠 \u003cstrong\u003e10\/10 mould resistance\u003c\/strong\u003e (ASTM D3273) · 🛡️ radon \u0026amp; methane barrier · ♻️ EPD (EN 15804)\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eICC-ES ESR-4715\u003c\/strong\u003e, Passivhaus certified \u0026amp; BBA approved\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/passive-purple-tested-certified\" title=\"Passive Purple Tested \u0026amp; Certified\"\u003eSee all test data \u0026amp; certifications →\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/builder-forgot-the-vapour-control-layer-how-to-fix-it\" title=\"My Builder Forgot the Vapour Control Layer? Here’s How to Fix It\"\u003eMy Builder Forgot the Vapour Control Layer? Here’s How to Fix It\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/what-is-a-vapour-control-layer-vcl-explained\" title=\"What Is a Vapour Control Layer? | VCL Explained\"\u003eWhat Is a Vapour Control Layer? | VCL Explained\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/what-is-airtightness-and-why-it-matters-for-net-zero-buildings\" title=\"What is Airtightness (and Why It Matters for Net Zero Buildings)\"\u003eWhat is Airtightness (and Why It Matters for Net Zero Buildings)\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Intelligent Membranes","offers":[{"title":"1","offer_id":52608802292052,"sku":"IM\/00PHSS","price":12.0,"currency_code":"GBP","in_stock":true},{"title":"12","offer_id":52608802324820,"sku":"IM\/00PHSB","price":144.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Passivhaus-Sealant_-White-and-Purple_png.webp?v=1784733153"},{"product_id":"passive-purple-retrofit-airtightness-5kg","title":"Passive Purple Retrofit - Retrofit Airtightness Brush Applied Paint (5kg)","description":"\u003cp style=\"box-sizing: inherit; margin: 20px 0px 0px; padding: 0px; font-size: 1.6rem; color: rgb(32, 32, 32); font-family: Montserrat, sans-serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;\"\u003eHere at Intelligent Membranes, we have a range specifically for retrofitting air tightness and vapour control. Not only are the products extremely effective, but they are also environmentally friendly. Airtightness and controlling vapour equals better energy efficiency and a healthier environment for the inhabitants.\u003c\/p\u003e\n\u003cp style=\"box-sizing: inherit; margin: 20px 0px 0px; padding: 0px; font-size: 1.6rem; color: rgb(32, 32, 32); font-family: Montserrat, sans-serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;\"\u003ePassive Purple: The fact that Passive Purple is a liquid membrane means that it adheres to the surface it is applied to making it very difficult to damage. Unlike a paper membrane which can be susceptible to cuts, It impregnates the surface it is adhered to and creates an airtight substrate filling any holes, cracks, penetration leaks or problem areas.\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eTested \u0026amp; Certified — worldwide\u003c\/h2\u003e\n\u003cp\u003eThe Retrofit brush grade is the Passive Purple liquid airtight membrane formulation — independently verified to \u003cstrong\u003eboth ASTM (ICC-ES) and EN standards\u003c\/strong\u003e:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e🌿 \u003cstrong\u003eFrench A+ indoor-air rating \u0026amp; Finnish M1 class\u003c\/strong\u003e — very low VOC emissions (EN 16516 \/ RTS)\u003c\/li\u003e\n\u003cli\u003e🏠 \u003cstrong\u003ePassive House Institute Class A airtight\u003c\/strong\u003e — 0.02 m³\/h·m² @ 50 Pa (EN 12114)\u003c\/li\u003e\n\u003cli\u003e🔒 \u003cstrong\u003eAir barrier material\u003c\/strong\u003e — 0.02 L\/s·m² at 75 Pa (ASTM E2178 · ICC-ES ESR-4715)\u003c\/li\u003e\n\u003cli\u003e🔥 \u003cstrong\u003eReaction to fire\u003c\/strong\u003e — Class A to ASTM E84; Euroclass C-s1,d0 to EN 13501-1 (B-s1,d0 with FRED)\u003c\/li\u003e\n\u003cli\u003e💧 \u003cstrong\u003eWatertight\u003c\/strong\u003e (EN 14891) \u0026amp; intelligent vapour control, Sd ~0.8–40 m (EN ISO 12572)\u003c\/li\u003e\n\u003cli\u003e🧱 \u003cstrong\u003eStrong adhesion\u003c\/strong\u003e — steel 2.7, CLT 1.83, gypsum 1.6, brick 1.5 N\/mm² (EN ISO 4624)\u003c\/li\u003e\n\u003cli\u003e🦠 \u003cstrong\u003e10\/10 mould resistance\u003c\/strong\u003e (ASTM D3273) · 🛡️ radon \u0026amp; methane barrier · ♻️ EPD (EN 15804)\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eICC-ES ESR-4715\u003c\/strong\u003e, Passivhaus certified \u0026amp; BBA approved\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/passive-purple-tested-certified\" title=\"Passive Purple Tested \u0026amp; Certified\"\u003eSee all test data \u0026amp; certifications →\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/how-to-retrofit-vapour-control-without-the-mess-bba-approved-passivhaus-certified-building-control-ready\" title=\"How to Retrofit Vapour Control Without the Mess\"\u003eHow to Retrofit Vapour Control Without the Mess\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/builder-forgot-the-vapour-control-layer-how-to-fix-it\" title=\"My Builder Forgot the Vapour Control Layer? Here’s How to Fix It\"\u003eMy Builder Forgot the Vapour Control Layer? Here’s How to Fix It\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/enerphit-explained-the-passivhaus-standard-for-old-buildings\" title=\"EnerPHit Explained – The Passivhaus Standard for Old Buildings\"\u003eEnerPHit Explained – The Passivhaus Standard for Old Buildings\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\u003cp\u003e\u003cstrong\u003eQuality assurance:\u003c\/strong\u003e \u003ca href=\"\/pages\/qa-sign-off-downloads\"\u003eDownload the free Installation \u0026amp; QA Record sign-off sheet (IM-QA-07)\u003c\/a\u003e for this product.\u003c\/p\u003e","brand":"Intelligent Membranes","offers":[{"title":"Purple","offer_id":52682700194132,"sku":"IM\/00RETB5PURPLE","price":55.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/PASSIVE-PURPLE-RETROFIT-5-KG.png?v=1784733619"},{"product_id":"passive-purple-retrofit-airtightness-10kg","title":"Passive Purple Retrofit - Retrofit Airtightness Spray\/Roller Paint (10kg)","description":"\u003cp style=\"box-sizing: inherit; margin: 20px 0px 0px; padding: 0px; font-size: 1.6rem; color: rgb(32, 32, 32); font-family: Montserrat, sans-serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;\"\u003eHere at Intelligent Membranes, we have a range specifically for retrofitting air tightness and vapour control. Not only are the products extremely effective, but they are also environmentally friendly. Airtightness and controlling vapour equals better energy efficiency and a healthier environment for the inhabitants.\u003c\/p\u003e\n\u003cp style=\"box-sizing: inherit; margin: 20px 0px 0px; padding: 0px; font-size: 1.6rem; color: rgb(32, 32, 32); font-family: Montserrat, sans-serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;\"\u003ePassive Purple Retrofit: The fact that Passive Purple Retrofit is a liquid membrane means that it adheres to the surface it is applied to making it very difficult to damage. Unlike a paper membrane which can be susceptible to cuts, It impregnates the surface it is adhered to and creates an airtight substrate filling any holes, cracks, penetration leaks or problem areas.\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eTested \u0026amp; Certified — worldwide\u003c\/h2\u003e\n\u003cp\u003ePassive Purple Retrofit is the Passive Purple liquid airtight membrane formulation — independently verified to \u003cstrong\u003eboth ASTM (ICC-ES) and EN standards\u003c\/strong\u003e:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e🌿 \u003cstrong\u003eFrench A+ indoor-air rating \u0026amp; Finnish M1 class\u003c\/strong\u003e — very low VOC emissions (EN 16516 \/ RTS)\u003c\/li\u003e\n\u003cli\u003e🏠 \u003cstrong\u003ePassive House Institute Class A airtight\u003c\/strong\u003e — 0.02 m³\/h·m² @ 50 Pa (EN 12114)\u003c\/li\u003e\n\u003cli\u003e🔒 \u003cstrong\u003eAir barrier material\u003c\/strong\u003e — 0.02 L\/s·m² at 75 Pa (ASTM E2178 · ICC-ES ESR-4715)\u003c\/li\u003e\n\u003cli\u003e🔥 \u003cstrong\u003eReaction to fire\u003c\/strong\u003e — Class A to ASTM E84; Euroclass C-s1,d0 to EN 13501-1 (B-s1,d0 with FRED)\u003c\/li\u003e\n\u003cli\u003e💧 \u003cstrong\u003eWatertight\u003c\/strong\u003e (EN 14891) \u0026amp; intelligent vapour control, Sd ~0.8–40 m (EN ISO 12572)\u003c\/li\u003e\n\u003cli\u003e🧱 \u003cstrong\u003eStrong adhesion\u003c\/strong\u003e — steel 2.7, CLT 1.83, gypsum 1.6, brick 1.5 N\/mm² (EN ISO 4624)\u003c\/li\u003e\n\u003cli\u003e🦠 \u003cstrong\u003e10\/10 mould resistance\u003c\/strong\u003e (ASTM D3273) · 🛡️ radon \u0026amp; methane barrier · ♻️ EPD (EN 15804)\u003c\/li\u003e\n\u003cli\u003e✅ \u003cstrong\u003eICC-ES ESR-4715\u003c\/strong\u003e, Passivhaus certified \u0026amp; BBA approved\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/passive-purple-tested-certified\" title=\"Passive Purple Tested \u0026amp; Certified\"\u003eSee all test data \u0026amp; certifications →\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/how-to-retrofit-vapour-control-without-the-mess-bba-approved-passivhaus-certified-building-control-ready\" title=\"How to Retrofit Vapour Control Without the Mess\"\u003eHow to Retrofit Vapour Control Without the Mess\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/builder-forgot-the-vapour-control-layer-how-to-fix-it\" title=\"My Builder Forgot the Vapour Control Layer? Here’s How to Fix It\"\u003eMy Builder Forgot the Vapour Control Layer? Here’s How to Fix It\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/enerphit-explained-the-passivhaus-standard-for-old-buildings\" title=\"EnerPHit Explained – The Passivhaus Standard for Old Buildings\"\u003eEnerPHit Explained – The Passivhaus Standard for Old Buildings\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\u003cp\u003e\u003cstrong\u003eQuality assurance:\u003c\/strong\u003e \u003ca href=\"\/pages\/qa-sign-off-downloads\"\u003eDownload the free Installation \u0026amp; QA Record sign-off sheet (IM-QA-07)\u003c\/a\u003e for this product.\u003c\/p\u003e","brand":"Intelligent Membranes","offers":[{"title":"Purple","offer_id":52682698490196,"sku":"IM\/00RETS10PURPLE","price":119.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/24.png?v=1784732057"},{"product_id":"wohler-smoke-stick","title":"Wohler S 100 Smoke Stick","description":"\u003cp\u003e\u003cspan\u003eThe \u003c\/span\u003e\u003cstrong\u003eWöhler S 100 Smokestick\u003c\/strong\u003e\u003cspan\u003e is an essential tool for visualising air flows! It features easy smoke generation and a convenient, replaceable smoke tank, making it a dependable choice for identifying leaks in and around buildings. With its battery operation and a smoke tank that lasts up to 900 seconds, you can count on its durability and efficiency.\u003c\/span\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cspan\u003eEasy smoke production\u003c\/span\u003e\u003cspan\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eInterchangable smoke tanks\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eBattery operated\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cspan\u003eThe Wohler S 100 Smoke Stick includes the following.\u003c\/span\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan\u003e1 x Wohler S 100 Smoke Stick\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003e2 x Wohler smoke tanks\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003e1,800 mAh lithium-ion battery\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eUSB-C charging cable\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003e1 x Metal flex hose with filter sponge\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003e1 x Rubber hose with filter sponge\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003e1 x Carry case\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/home_blog\/the-science-behind-airtight-buildings\" title=\"The Science Behind Airtight Buildings\"\u003eThe Science Behind Airtight Buildings\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/what-is-airtightness-and-why-it-matters-for-net-zero-buildings\" title=\"What is Airtightness (and Why It Matters for Net Zero Buildings)\"\u003eWhat is Airtightness (and Why It Matters for Net Zero Buildings)\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/builder-forgot-the-vapour-control-layer-how-to-fix-it\" title=\"My Builder Forgot the Vapour Control Layer? Here’s How to Fix It\"\u003eMy Builder Forgot the Vapour Control Layer? Here’s How to Fix It\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Wohler","offers":[{"title":"Default Title","offer_id":52608802816340,"sku":"IM\/00WSP","price":199.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/12174_649407279_5.jpg?v=1781215461"},{"product_id":"wohler-smoke-tanks-packof3","title":"Wohler Smoke Tanks (Pack Of 3 Tanks)","description":"\u003cp\u003eWohler Smoke Tanks (Pack Of 3 Tanks) - Refill tanks for the Wohler S 100 Smoke Stick\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/home_blog\/the-science-behind-airtight-buildings\" title=\"The Science Behind Airtight Buildings\"\u003eThe Science Behind Airtight Buildings\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/what-is-airtightness-and-why-it-matters-for-net-zero-buildings\" title=\"What is Airtightness (and Why It Matters for Net Zero Buildings)\"\u003eWhat is Airtightness (and Why It Matters for Net Zero Buildings)\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Wohler","offers":[{"title":"Default Title","offer_id":52608802849108,"sku":"IM\/00WST","price":93.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/airtracer_cartridge.jpg?v=1784733584"},{"product_id":"passive-purple-internal-vapour-control-bundle-pack","title":"The BIG BOY Bundle","description":"\u003ch2\u003eWhat is and how to use Passive Purple?\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003ePassive Purple Intelligent liquid airtight vapour control membrane is an airtight coating applied using an airless spray device to all areas of the external envelope (warm side of the insulation) of a building. This includes difficult connection areas such as floors, walls, roofs, and joists.\u003c\/li\u003e\n\u003cli\u003eWhen Passive Purple Intelligent Membrane is used on the warm side of the insulation, it can be applied to either face of the external envelope to create a vapour control layer.\u003c\/li\u003e\n\u003cli\u003eTo install Passive Purple Intelligent Membrane, ensure the surface is solid, dust-free, and closed before starting the application.\u003c\/li\u003e\n\u003cli\u003eA closed surface means all holes and joints must be sealed beforehand:\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eLarge holes and joints (\u0026gt;5mm):\u003c\/strong\u003e seal with fast-setting cement-based products or polyurethane foam.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSmall holes and joints (2–5mm):\u003c\/strong\u003e seal directly using Passive Purple Liquid Brush, the thicker brush-applied version.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003eAfter preparation, Passive Purple can be spray-applied with an airless machine, allowing a single operator to apply up to \u003cstrong\u003e300 m² per day\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003eFor small projects, such as private houses, Passive Purple Brush can be applied using a flat paintbrush.\u003c\/li\u003e\n\u003cli\u003eWall-to-ceiling connections must also be made airtight, especially where different construction materials meet, such as brick to concrete or steel to concrete.\u003c\/li\u003e\n\u003cli\u003eDifferent construction materials react differently to changes in humidity and temperature and move at different rates. This can cause small cracks in finishes, leading to air leaks, reduced energy performance, and an increased risk of damp and mould.\u003c\/li\u003e\n\u003cli\u003eBoth airtight paints can be used for wall-to-ceiling connections: Passive Purple spray-applied and Passive Purple Brush.\u003c\/li\u003e\n\u003cli\u003eGet in touch with our team at \u003ca href=\"mailto:info@intelligentmembranes.com\"\u003einfo@intelligentmembranes.com\u003c\/a\u003e to learn more.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eNote:\u003c\/strong\u003e If you do not have an airless sprayer but still wish to install Passive Purple yourself, a roller-applied version is also available. It may take a little longer, but it still delivers reliable airtight performance.\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/what-is-a-vapour-control-layer-vcl-explained\" title=\"What Is a Vapour Control Layer? | VCL Explained\"\u003eWhat Is a Vapour Control Layer? | VCL Explained\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/builder-forgot-the-vapour-control-layer-how-to-fix-it\" title=\"My Builder Forgot the Vapour Control Layer? Here’s How to Fix It\"\u003eMy Builder Forgot the Vapour Control Layer? Here’s How to Fix It\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/what-is-airtightness-and-why-it-matters-for-net-zero-buildings\" title=\"What is Airtightness (and Why It Matters for Net Zero Buildings)\"\u003eWhat is Airtightness (and Why It Matters for Net Zero Buildings)\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Intelligent Membranes","offers":[{"title":"Default Title","offer_id":52608803111252,"sku":"IM\/00PPBBB","price":564.93,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/The-Big-Boy-Bundle.png?v=1784733561"},{"product_id":"the-goat-sealant-airtight-flexible-sealant","title":"The GOAT Liquid Grommet - Airtight \u0026 Flexible Sealant (Box of 6 310ml mastic tubes)","description":"\u003cp\u003e\u003cstrong\u003eThe GOAT Liquid Grommet\u003c\/strong\u003e is a fast-curing, airtight and flexible sealant supplied as a box of 6 × 310ml mastic tubes. Ideal for sealing service penetrations, corners and junctions, it becomes waterproof within minutes of application and cures to form a durable, airtight and watertight seal.\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eSee it on site in 360°\u003c\/h2\u003e\n\u003cp\u003eA service penetration sealed with The GOAT, applied in a deliberate key shape: the extended section below the opening follows the planned cable route, so the cable emerges through sealant rather than through a gap.\u003c\/p\u003e\n\u003cfigure style=\"margin:20px 0;padding:0;\"\u003e\n\u003cdiv style=\"position:relative;padding-top:56.25%;background:#f4f4f4;border-radius:6px;overflow:hidden;\"\u003e\u003ciframe src=\"https:\/\/kuula.co\/share\/Ln1BS?logo=1\u0026amp;info=1\u0026amp;fs=1\u0026amp;vr=0\u0026amp;zoom=1\u0026amp;sd=1\u0026amp;thumbs=1\" title=\"The GOAT liquid grommet, a key-shaped seal following the cable route — 360 degree site tour\" loading=\"lazy\" frameborder=\"0\" scrolling=\"no\" allow=\"xr-spatial-tracking; gyroscope; accelerometer\" allowfullscreen=\"\" style=\"position:absolute;top:0;left:0;width:100%;height:100%;border:0;\"\u003e\u003c\/iframe\u003e\u003c\/div\u003e\n\u003cfigcaption style=\"margin-top:10px;font-size:0.9rem;\"\u003eClick and drag to look around. \u003ca href=\"\/pages\/360-images\"\u003eSee all our 360° site tours\u003c\/a\u003e.\u003c\/figcaption\u003e\n\u003c\/figure\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/nhbc-standards-2023-waterproof-membranes-as-a-tanking-system\" title=\"NHBC Standards 2023: Waterproof Membranes as a Tanking System\"\u003eNHBC Standards 2023: Waterproof Membranes as a Tanking System\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/five-things-about-waterproofing\" title=\"Five Things About Waterproofing\"\u003eFive Things About Waterproofing\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Intelligent Membranes","offers":[{"title":"Default Title","offer_id":52608803144020,"sku":"IM\/GOATGB","price":60.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/The-GOAT-Sealant-3.png?v=1784732469"},{"product_id":"passive-purple-x-10kg-white-spray-roller","title":"Passive Purple X (10kg) - Spray\/Roller","description":"\u003cp\u003e\u003cspan lang=\"EN-GB\"\u003eKey characteristics of Passive Purple X (shares Passive Purple External's certified performance): \u003c\/span\u003e\u003c\/p\u003e\n\u003cul type=\"disc\"\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eFireclass B\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eRaintight but vapour breathable\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eAirtight\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eUV resistant\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eAnti-fungus\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eSelf-cleaning \/ reduced dirt pickup caused by UV netting\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eCrack-bridging\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eCarbonatation block (for concrete); realkalising (concrete)\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan lang=\"EN-GB\"\u003eProtection against salts (for roads) (concrete structures).\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003eCan also be used as a protective coating on concrete as anticarbonatation on concrete\/cement coating.\u003c\/li\u003e\n\u003cli\u003eInternal and External uses\u003c\/li\u003e\n\u003cli\u003eSmoke Tight\u003c\/li\u003e\n\u003cli\u003eLets the Building or substrate breathe\u003c\/li\u003e\n\u003cli\u003eIntelligent Moisture management\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv style=\"border-top: 2px solid #b5985a; margin-top: 28px; padding-top: 18px;\"\u003e\n\u003ch2 style=\"color: #4a1a6e;\"\u003eTested \u0026amp; Certified — fire-rated, watertight \u0026amp; breathable\u003c\/h2\u003e\n\u003cp\u003ePassive Purple X shares the certified Passive Purple External performance, independently verified to both European (EN) and US (ASTM) standards:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e🔥 \u003cstrong\u003eReaction to fire Euroclass B-s1,d0\u003c\/strong\u003e (EN 13501-1, on A1 substrates ≥653 kg\/m³) \u0026amp; \u003cstrong\u003eASTM E84 Class A\u003c\/strong\u003e (Flame Spread 0 \/ Smoke 15)\u003c\/li\u003e\n\u003cli\u003e💧 \u003cstrong\u003eWatertight Class W1\u003c\/strong\u003e (EN 13859-2) \u0026amp; water permeability Class W3 (EN 1062-3); near-zero water absorption (EN 16302)\u003c\/li\u003e\n\u003cli\u003e🌬️ \u003cstrong\u003eBreathable \/ vapour-open\u003c\/strong\u003e — Sd ≈ 0.6 m (EN ISO 12572)\u003c\/li\u003e\n\u003cli\u003e🧱 \u003cstrong\u003eCrack-bridging\u003c\/strong\u003e A3 (23°C) \/ A4 (-10°C) (EN 1062-7) \u0026amp; CO₂ \/ carbonation barrier Class C1 (EN 1062-6)\u003c\/li\u003e\n\u003cli\u003e☀️ \u003cstrong\u003eUV-stable\u003c\/strong\u003e (strength increases after 500 h UV) · low-emission \u003cstrong\u003eEMICODE EC2\u003c\/strong\u003e · anti-fungus (rating 0)\u003c\/li\u003e\n\u003cli\u003e🇬🇧 \u003cstrong\u003eKiwa BDA Agrément\u003c\/strong\u003e (BAW-21-214-P-A-UK) · Passive House component (phB) · US ICC-ES AC212 water-resistive barrier\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/passive-purple-tested-certified\" title=\"Tested \u0026amp; Certified\"\u003eSee all test data \u0026amp; certifications →\u003c\/a\u003e · read about \u003ca href=\"\/blogs\/educational\/passive-purple-external-fire-class-b-watertight-breathable\"\u003ePassive Purple External\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top: 2px solid #b5985a; margin-top: 28px; padding-top: 18px;\"\u003e\n\u003ch2 style=\"color: #4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/airtight-and-vapour-control-for-high-rise-re-cladding-installed-from-the-outside-i\" title=\"Airtight and Vapour Control for High-Rise Re-Cladding\"\u003eAirtight and Vapour Control for High-Rise Re-Cladding\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/the-airtightness-challenge-facing-modern-construction-why-blockwork-alone-is-no-longer-enough\" title=\"The Airtightness Challenge: Why Blockwork Alone Is No Longer Enough\"\u003eThe Airtightness Challenge: Why Blockwork Alone Is No Longer Enough\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/how-to-retrofit-vapour-control-without-the-mess-bba-approved-passivhaus-certified-building-control-ready\" title=\"How to Retrofit Vapour Control Without the Mess\"\u003eHow to Retrofit Vapour Control Without the Mess\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cp\u003e\u003cstrong\u003eQuality assurance:\u003c\/strong\u003e \u003ca href=\"\/pages\/qa-sign-off-downloads\"\u003eDownload the free Installation \u0026amp; QA Record sign-off sheet (IM-QA-06)\u003c\/a\u003e for this product.\u003c\/p\u003e","brand":"Intelligent Membranes","offers":[{"title":"White","offer_id":52683125358932,"sku":"IM\/00PPXS10WHITE","price":119.99,"currency_code":"GBP","in_stock":true},{"title":"Cream","offer_id":52683125260628,"sku":"IM\/00PPXS10CREAM","price":119.99,"currency_code":"GBP","in_stock":true},{"title":"Black","offer_id":52683125293396,"sku":"IM\/00PPXS10BLACK","price":119.99,"currency_code":"GBP","in_stock":true},{"title":"Purple","offer_id":52683125326164,"sku":"IM\/00PPXS10PURPLE","price":119.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/25-1.png?v=1784732307"},{"product_id":"passive-purple-external-airtight-fire-rated-facade-waterproofing-membrane-10kg-cream-spray-roller","title":"Passive Purple External Airtight Fire Rated Façade Waterproofing Membrane (10kg) - Spray \/ Roller","description":"\u003ch3\u003eKey Characteristics of Passive Purple External\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003ePassive Purple External\u003c\/strong\u003e is a \u003cstrong\u003eFire Class B (Euroclass B-s1,d0) liquid-applied airtight paint\u003c\/strong\u003e for both \u003cstrong\u003einternal and external applications\u003c\/strong\u003e. It combines airtightness, weather protection, and intelligent moisture management in a single certified solution.\u003c\/p\u003e\n\u003ch4\u003eKey Benefits \u0026amp; Features\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e🔥 \u003cstrong\u003eFire Class B\u003c\/strong\u003e – exceptional fire resistance, setting it apart from standard membranes.\u003c\/li\u003e\n\u003cli\u003e🌧 \u003cstrong\u003eRaintight \u0026amp; Vapour Breathable\u003c\/strong\u003e – keeps water out while allowing moisture to escape, ensuring a healthy building fabric.\u003c\/li\u003e\n\u003cli\u003e🔒 \u003cstrong\u003eAirtight \u0026amp; Smoke-Tight\u003c\/strong\u003e – delivers a complete barrier to uncontrolled air leakage and smoke movement.\u003c\/li\u003e\n\u003cli\u003e☀️ \u003cstrong\u003eUV Resistant \u0026amp; Self-Cleaning\u003c\/strong\u003e – long-term durability with reduced dirt pickup and surface staining.\u003c\/li\u003e\n\u003cli\u003e🦠 \u003cstrong\u003eAnti-Fungus Protection\u003c\/strong\u003e – prevents mould growth and safeguards indoor air quality.\u003c\/li\u003e\n\u003cli\u003e🧱 \u003cstrong\u003eCrack-Bridging\u003c\/strong\u003e – maintains airtightness even where movement or minor cracks occur.\u003c\/li\u003e\n\u003cli\u003e🧪 \u003cstrong\u003eConcrete Protection\u003c\/strong\u003e – blocks carbonation, provides realkalisation, and shields against salts from roads and de-icing.\u003c\/li\u003e\n\u003cli\u003e🌍 \u003cstrong\u003eDual Purpose\u003c\/strong\u003e – suitable for \u003cstrong\u003einternal and external\u003c\/strong\u003e applications across retrofit and new-build projects.\u003c\/li\u003e\n\u003cli\u003e💨 \u003cstrong\u003eIntelligent Moisture Management\u003c\/strong\u003e – allows the substrate to breathe, balancing vapour openness with airtight performance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eWith \u003cstrong\u003ePassive Purple External\u003c\/strong\u003e, you get \u003cstrong\u003eairtightness, weather resistance, and long-term structural protection\u003c\/strong\u003e in one advanced, certified liquid membrane — ideal for timber frame, retrofit, and high-performance construction projects.\u003c\/p\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eTested \u0026amp; Certified — fire-rated, watertight \u0026amp; breathable\u003c\/h2\u003e\n\u003cp\u003eIndependently certified to both European (EN) and US (ASTM) standards:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e🔥 \u003cstrong\u003eReaction to fire Euroclass B-s1,d0\u003c\/strong\u003e (EN 13501-1, on A1 substrates ≥653 kg\/m³) \u0026amp; \u003cstrong\u003eASTM E84 Class A\u003c\/strong\u003e (Flame Spread 0 \/ Smoke 15)\u003c\/li\u003e\n\u003cli\u003e💧 \u003cstrong\u003eWatertight Class W1\u003c\/strong\u003e (EN 13859-2) \u0026amp; water permeability Class W3 (EN 1062-3); near-zero water absorption (EN 16302)\u003c\/li\u003e\n\u003cli\u003e🌬️ \u003cstrong\u003eBreathable \/ vapour-open\u003c\/strong\u003e — Sd ≈ 0.6 m (EN ISO 12572), so the wall dries outward\u003c\/li\u003e\n\u003cli\u003e🧱 \u003cstrong\u003eCrack-bridging\u003c\/strong\u003e A3 (23°C) \/ A4 (-10°C) (EN 1062-7) \u0026amp; CO₂ \/ carbonation barrier Class C1 (EN 1062-6)\u003c\/li\u003e\n\u003cli\u003e☀️ \u003cstrong\u003eUV-stable\u003c\/strong\u003e (strength increases after 500 h UV) · low-emission \u003cstrong\u003eEMICODE EC2\u003c\/strong\u003e · anti-fungus (rating 0)\u003c\/li\u003e\n\u003cli\u003e🇬🇧 \u003cstrong\u003eKiwa BDA Agrément\u003c\/strong\u003e (BAW-21-214-P-A-UK) · Passive House component (phB) · US ICC-ES AC212 water-resistive barrier\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003ca href=\"\/pages\/passive-purple-tested-certified\" title=\"Tested \u0026amp; Certified\"\u003eSee all test data \u0026amp; certifications →\u003c\/a\u003e · read about \u003ca href=\"\/blogs\/educational\/passive-purple-external-fire-class-b-watertight-breathable\"\u003ePassive Purple External\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003e🌎 Tested for World Markets — ASTM (US) \u0026amp; EN (Europe)\u003c\/h2\u003e\n\u003cp\u003ePassive Purple External is fire rated to \u003cstrong\u003eASTM E84 Class A (US)\u003c\/strong\u003e and \u003cstrong\u003eEN fire Class B (Europe)\u003c\/strong\u003e — tested to US ASTM standards alongside its European certifications, so the same fire rated façade membrane can be specified on both sides of the Atlantic.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eUS architects \u0026amp; specifiers: \u003ca href=\"\/pages\/us-specifications\" title=\"US specifications in CSI MasterFormat\"\u003edownload the US specifications (CSI MasterFormat)\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli\u003eUS supply \u0026amp; install: \u003ca href=\"\/pages\/chicago\" title=\"Passive Purple Chicago — distributed and installed by WickRight\"\u003eWickRight, our Chicago distribution \u0026amp; installation partner\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli\u003eFire rated range: \u003ca href=\"\/collections\/fire-protection\" title=\"Fire protection collection\"\u003eshop the full fire protection collection\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border-top:2px solid #b5985a;margin-top:28px;padding-top:18px;\"\u003e\n\u003ch2 style=\"color:#4a1a6e;\"\u003eRelated Guides\u003c\/h2\u003e\n\u003cp\u003eHelpful guides related to this product:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/airtight-and-vapour-control-for-high-rise-re-cladding-installed-from-the-outside-i\" title=\"Airtight and Vapour Control for High-Rise Re-Cladding\"\u003eAirtight and Vapour Control for High-Rise Re-Cladding\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/educational\/what-is-airtightness-and-why-it-matters-for-net-zero-buildings\" title=\"What is Airtightness (and Why It Matters for Net Zero Buildings)\"\u003eWhat is Airtightness (and Why It Matters for Net Zero Buildings)\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/blogs\/news\/damp-walls-two-breathable-solutions-that-actually-work\" title=\"Damp Walls? Two Breathable Solutions That Actually Work\"\u003eDamp Walls? Two Breathable Solutions That Actually Work\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\u003cp\u003e\u003cstrong\u003eQuality assurance:\u003c\/strong\u003e \u003ca href=\"\/pages\/qa-sign-off-downloads\"\u003eDownload the free Installation \u0026amp; QA Record sign-off sheet (IM-QA-05)\u003c\/a\u003e for this product.\u003c\/p\u003e","brand":"Intelligent Membranes","offers":[{"title":"Purple","offer_id":52683132174676,"sku":"IM\/00PPE10PURPLE","price":119.99,"currency_code":"GBP","in_stock":true},{"title":"Black","offer_id":52683132141908,"sku":"IM\/00PPE10BLACK","price":119.99,"currency_code":"GBP","in_stock":true},{"title":"Cream","offer_id":52683132207444,"sku":"IM\/00PPE10CREAM","price":119.99,"currency_code":"GBP","in_stock":true},{"title":"White","offer_id":52683132240212,"sku":"IM\/00PPE10WHITE","price":119.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/2104\/7636\/files\/Passive_Purple_External_Purple_10kg_-_Airtight_Fire_Rated_Facade_Waterproofing_Membrane.png?v=1784732199"}],"url":"https:\/\/intelligentmembranes.com\/collections\/airtight-membranes.oembed","provider":"Intelligent Membranes","version":"1.0","type":"link"}