Vapour and air control membranes for building assemblies
Vapour and air barrier procurement starts with the assembly position, not the roll alone. Specify the layer location, membrane type, joint treatment and penetration accessories so suppliers can quote a compatible package.
Start with the right material groups.
Vapour control layers
Provide the layer position and required vapour resistance from the approved assembly detail. List the membrane, joint tapes and sealants separately.
Air barrier membranes
Define the airtightness target, substrate and continuity requirements. Ask suppliers to state how laps, sills and service penetrations remain continuous.
Accessory package
Request tapes, primers, corner patches, pipe collars and fixings matched to the membrane. Confirm which package supplies each accessory type.
A material price is only part of the package.
One schedule, clearly separated scopes. This is a request outline, not an installation drawing.
Included materials
List each vapour or air control membrane by assembly position, roll dimensions and net area to be covered.
Connections & interfaces
Identify tapes, primers, mechanical fixings, corner patches and penetration accessories; state whether they are included or supplied separately.
Confirm separately
Confirm substrate preparation, temporary exposure limits, waste allowances and inspection responsibilities with the project team and supplier.
Six details that make offers clearer.
- Product designation and position
- State the project-prescribed membrane type, assembly position and required resistance class or performance target.
- Substrate and surface condition
- Describe the adjoining material, surface finish and any primer needed before the membrane is fixed.
- Roll format and net area
- Request roll width, length and the net coverage area, keeping overlap and waste allowances separate.
- Lap and joint treatment
- Ask how the supplier proposes to treat laps, T-joints and membrane transitions at the specified detail.
- Penetrations and service interfaces
- List pipes, ducts, outlets and structural connections that cross the membrane plane.
- Temporary exposure and storage
- Request the maximum exposed period, UV limits, packaging and protected storage requirements.
| Item & description | Quantity |
|---|---|
| VB-01Vapour control membrane for warm-side assembly position; roll size and resistance class per project specification. | 1400 m² |
| VB-02Air barrier membrane with matched joint tape, corner patches and pipe collars for the approved envelope detail. | 36 rolls |
Example quantities only; no live prices or supplier offers. Use your project schedule for final values and ask suppliers to list deviations.
Three checks before you decide.
Layer position confirmed
Check the quoted membrane matches the specified warm-side or cold-side location before comparing brands.
Accessory continuity
Verify that tapes, primers and penetration components are listed against the same assembly detail.
Coverage versus net area
Compare net measured area with roll coverage and confirm how laps, waste and site cuts are handled.
Details worth clarifying early.
Is a vapour control layer the same as an air barrier?
They perform different control functions. Identify which function the assembly requires and ask the supplier to confirm the proposed membrane for that position.
What information is needed to compare membrane quotations?
State the assembly position, project performance requirement, substrate, roll dimensions and accessory list. Ask for the supplier's proposal against that same data set.
Turn your material schedule into a request.
Create a Matravo account to prepare your request. For account or sourcing-flow questions, visit support.