Vapour permeance
Transmission through a specimen under specified conditions; it does not measure air leakage.
Material family: Construction, roofing and geosynthetics
Where it matters
Assembly-specific air, vapour and liquid-water control.
Testing and verification
Separate material permeance, assembly leakage, fire/code evidence and field continuity.
Related guides
Related products and materials
- Water-Resistive Barriers
- Air and Vapor Control Membranes
- Industrial Sealants & Joint Sealing
- Roofing Membranes & Underlayment
General information for preliminary evaluation; not independently reviewed or certified. Confirm grades, standards and suitability with the manufacturer for your application. Interpret within the exact material, grade and test method.