Vapour Barrier Installation Windsor Park Edmonton

Poly and air sealing in Windsor Park before the board goes on

Alberta winters put a large vapour drive from inside to outside, so the barrier belongs on the warm side of the insulation. Getting the position right matters as much as getting it sealed: a second barrier on the cold side traps moisture in the assembly with no way to dry.

• Rim joists air-sealed before insulating
• Electrical boxes poly-hatted and sealed
• Seams lapped at framing and sealed, not just taped
• Left ready for inspection before boarding
• Window and door returns detailed properly
• Poly on the warm side of the insulation

Vapour Barrier Installation Windsor Park Edmonton

Never two barriers

Windsor Park drywall in context

Where poly is the wrong choice

What a vapour barrier is not

The parts an inspector looks at first

Sealing at the electrical boxes

Seams belong on framing

Simple, clean, on schedule — Vapour Barrier Installation in Windsor Park Edmonton

Vapour Barrier Installation Windsor Park Edmonton: your questions answered

Is poly always the right answer?

No. Some assemblies, such as insulated concrete basements or walls with exterior rigid insulation, are designed to dry inward, and poly stops that. We look at the whole assembly rather than defaulting.

What about outlets on exterior walls?

Each one is a deliberate hole. They need poly hats or airtight boxes sealed to the sheet. Taping poly to the front of an ordinary box does not last once board is fastened over it, and it is the most common leak we find.

Does it matter where the sheets overlap?

Yes. A lap must land on solid framing and be sealed with acoustical sealant compressed between layers. An unsupported lap taped across a cavity flexes with pressure changes and works loose.

Can I add poly over insulation that already has a facing?

Usually no. Two retarders leave any moisture that gets in with no direction to dry. We check what is already in the wall before adding to it rather than assuming the cavity is bare.

Should I use poly or a smart membrane?

Most straightforward Windsor Park walls are fine with 6-mil poly, continuous and sealed. A variable-permeance membrane is worth it on retrofits and some basement details because it gives the assembly a drying path in both directions.

Is a basement wall done the same way as an upstairs wall?

No. A basement wall can take moisture from the ground too, so poly detailed like an above-grade wall can trap moisture against the concrete. The insulation is held off the concrete so the wall can dry, with vapour control on the warm side.