NHBC Standards 2023: Waterproof Membranes as a Tanking System
NHBC Standards 2023 Update: Waterproofing Requirements for Bathrooms and Wet Areas
The National House Building Council (NHBC), the UK’s leading provider of warranty and insurance for new homes, sets the benchmark for construction standards across the industry.
As part of the NHBC Standards 2023 updates introduced in July 2023, new requirements have been implemented regarding waterproofing in bathrooms and wet areas.
Under the updated guidance, all bath and shower enclosures, wet rooms and bathroom pods must incorporate an impermeable liquid-applied waterproofing membrane behind tiled finishes. This prevents the ingress of water and moisture into the building structure and reduces long-term damage and insurance claims.
These requirements apply to all housebuilders and developers in the UK. The updated standards are mandatory for every NHBC-registered home where foundations are begun on or after 1st January 2024.
Updated Wall Tiling Requirements - Clause 9.2.5
Due to a rise in insurance claims relating to failures around baths, shower enclosures and bathroom pods, NHBC has revised its guidance under Clause 9.2.5 ‘Ceramic Wall Tiling’.
The updated position makes clear that:
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Gypsum plasters must not be used in areas subject to repeated or persistent wetting.
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Wet areas, including shower enclosures and wet rooms, require backing surfaces to be protected with a suitable tanking system.
Within NHBC Standards 2023 (9.2/06, Table 2), liquid-applied waterproofing systems are identified as a compliant solution for protecting walls and floors in bathrooms and wet rooms.
NHBC Accepted Products and Compliance
To remain compliant, only suitable NHBC-accepted products that create a watertight covering for walls and floors should be specified.
Intelligent Membranes’ liquid-applied waterproofing systems meet these requirements. Our products are:
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NHBC accepted
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CE marked
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Compliant with EAD 030352-00-0503
This ensures alignment with the updated NHBC waterproofing regulations.
Poseidon Liquid Waterproof Membrane
Poseidon is a polymer-based liquid-applied waterproof membrane that cures to form a flexible, durable barrier.
It is specifically designed for:
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Concrete and cement-based surfaces
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Shower enclosures
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Bathrooms and wet rooms
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Steam areas
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Bathroom pods
With high crack-bridging properties, Poseidon provides an impervious waterproof layer prior to tiling. It is an ideal tanking solution for protecting bath and shower areas in line with the updated NHBC requirements.
The GOAT Waterproof Sealant
For complete waterproofing protection, corner detailing is critical.
The GOAT crack-bridging sealant is a fast-curing reactive polymer that becomes waterproof within one minute of application. Once cured, it forms a flexible, airtight and waterproof seal.
It should be applied to:
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Internal corners
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Wall-to-floor junctions
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Transitions in wet rooms
This ensures full crack-bridging protection before the application of Poseidon as part of a complete NHBC-compliant tanking system.
Technical Guidance and Application
To support compliance with NHBC Standards 2023, we have produced a technical guide outlining how and where to install waterproofing systems in bathrooms and wet rooms.
The diagrams are based on the NHBC Standards 2023 guidance and adapted to demonstrate best practice when using Intelligent Membranes’ waterproofing products.
Poseidon can be applied by:
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Spray
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Roller
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Brush
The GOAT sealant is applied using a standard mastic gun, ensuring quick and straightforward installation on site.
Stay Compliant with NHBC Standards 2023
With the July 2023 updates now in effect for all NHBC-registered homes with foundations started from 1st January 2024, specifying the correct liquid-applied waterproofing system is essential.
Intelligent Membranes provides NHBC-accepted waterproofing solutions designed to protect bath and shower enclosures, wet rooms and bathroom pods, ensuring compliance while delivering long-term performance.
If you require a liquid-applied waterproofing system that meets NHBC standards, contact our team today to discuss your project requirements.