Passive Purple air barrier — tested to ASTM E2178

Tested Air Barrier: Passive Purple Meets ASTM E2178

Airtightness is a global concern, but the standards that prove it are not. Europe specifies to EN; the United States specifies to ASTM and asks for code-compliance evidence on each project. Passive Purple is one of the rare air-barrier products tested to both — so it can be written into a specification on either side of the Atlantic. 🔒

What ASTM E2178 measures

ASTM E2178 is the US standard test method for the air leakage of a building material. It measures how much air passes through the material itself under a defined pressure difference, and it is the test that decides whether a product qualifies as an air-barrier material. The recognised threshold is an air leakage of ≤0.02 L/(s·m²) at 75 Pa. A material below that line is accepted as an air barrier; above it, it is not.

Passive Purple was tested to ASTM E2178 by ICC NTA in the USA, with these results:

  • Total air leakage of 0.01 L/(s·m²) at 75 Pa — half the qualifying threshold, so the report meets the air-barrier criteria comfortably.
  • Passive Purple air permeance: 0.000011 L/(s·Pa·m²).
  • Passive Purple Brush air permeance: 0.000002 L/(s·Pa·m²).

These are the figures a US air-barrier specification asks for, delivered by an accredited independent laboratory.

From test results to code acceptance

Passing a test is one thing; showing code compliance on a project is another. In the US, acceptance is through the test reports themselves, submitted to the code official or authority having jurisdiction (AHJ) for each project. Passive Purple and Passive Purple Brush have been independently tested as:

  • A qualifying air-barrier material to ≤0.02 L/(s·m²) at 75 Pa; and
  • A Class A material for surface burning characteristics (tested to ASTM E84). 🔥

For a US specifier, ask Intelligent Membranes for the test reports to include in your submittal, and apply the membrane at the specified film thickness. For wood or OSB substrates, check fire and finish requirements for your project with us and your code official.

The same product, proven to two standards

This is the point that matters for anyone working across markets. It is not that Intelligent Membranes sells one product in Europe and a different one in America. It is the same Passive Purple, proven independently to both regimes:

  • Europe: Passive House Institute Class A (phA) to EN 12114, confirmed at Ghent University.
  • United States: air-barrier material to ASTM E2178 and Class A to ASTM E84.

For a design practice with projects in more than one country, that removes a genuine headache. You are not sourcing and re-detailing an alternative product to satisfy a different rulebook — the airtight layer, the application method and the details stay consistent, and the paperwork is already in place for both. And because Airtight White is the same formulation as Passive Purple, simply white-pigmented, these certifications carry across to it as well.

Specifying in the US market

To make US specification straightforward, US specifications are available in CSI MasterFormat — the standard specification structure American architects and specifiers already work in. Supply and installation on the ground is supported by a Chicago-based distribution and install partner, WickRight, so specifying the product does not mean sourcing it from overseas with no local support.

Why it matters

An air barrier is only as good as the evidence behind it. A liquid-applied membrane that carries a real ASTM E2178 result and an ASTM E84 Class A result gives US specifiers the test evidence they need to write it into a spec and submit it to the code official — and the parallel EN certification means a single product answers the requirements of both continents.

You can review the full reports and classifications on our full test data & certifications page, and see the product here: Passive Purple. Whether your project answers to EN or to ASTM, the airtight layer is already certified.

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