Vapour Barrier Installation Terra Losa Edmonton

Poly and air sealing in Terra Losa 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
• Left ready for inspection before boarding
• Poly on the warm side of the insulation
• Seams lapped at framing and sealed, not just taped
• Window and door returns detailed properly

Vapour Barrier Installation Terra Losa Edmonton

Inspecting it before it is covered

Terra Losa drywall in context

Windows, doors and the returns around them

Renovations, and meeting an existing barrier

Basement walls, where the rules change

The parts an inspector looks at first

Bathrooms, kitchens and the wet rooms

Simple, clean, on schedule — Vapour Barrier Installation in Terra Losa Edmonton

Vapour Barrier Installation Terra Losa Edmonton: your questions answered

Why is there staining around my window reveals?

Usually the vapour barrier return at the window was torn or tucked rather than sealed. It is a cold junction, so condensation shows there first — often as staining or mould at the reveal.

Is it a problem to have poly on both sides?

Yes. Two barriers trap moisture between them with no direction to dry. It is a real mistake we still find in renovated Terra Losa walls, and it stays invisible until the damage shows.

Is a bathroom done differently?

Same rules, larger consequences. A bathroom pushes far more vapour into the wall, so a gap shows up faster. The fan housing and duct are sealed rather than trimmed around, and we check the fan vents outside rather than into the attic.

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.

Will this stop water coming through my basement wall?

No, and installing it would hide the evidence. Water coming through a wall is a drainage and waterproofing problem. Vapour control manages moisture in the air, not liquid water, and we will say so rather than board over it.

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.