Is the vapour barrier the same as an air barrier?

Not by itself. Poly slows vapour diffusion; sealed properly it also slows air, and unsealed it does very little of either. The sealing is what turns a sheet of plastic into a working assembly.

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.

Will this pass inspection?

It is built to what the code asks for on your permit, and we leave it visible and sequence to your inspection date rather than boarding ahead. If an inspector raises something, we want the note directly so it is fixed from the actual reason.

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.

Should I use poly or a smart membrane?

Most straightforward Avonmore 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.

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.

Vapour Barrier Installation Avonmore Edmonton | 6 Mil Poly

Vapour barrier in Avonmore, sealed as a continuous plane

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.

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

Sealing at the electrical boxes

Every box is a hole

An outlet or switch on an exterior Avonmore wall is a deliberate opening straight through the barrier.

The fix

Poly hats or airtight boxes, sealed to the sheet. Taping the poly to the front of an ordinary box does not last, because the board is fastened over it and the seal breaks. This is the single most common leak we find behind finished walls.

Avonmore drywall in context

About Avonmore

Avonmore was developed during the 1950s and features primarily single family homes.

What we see in Avonmore

In Avonmore the drywall work is plaster and lath repair, popcorn and stipple ceiling removal, careful patching into original surfaces. We confirm what your home actually needs on site, in writing, before anything starts.

Warm side, always

The one rule everything else follows

The barrier goes on the heated side of the insulation. In an Avonmore climate that is the room side of an exterior wall.

Why position decides everything

Put it on the cold side and you have placed a moisture stop exactly where indoor humidity will condense against it, inside the wall, where nothing dries and nothing is visible until the damage is done.

Why the warm side, and why only one

Which way the moisture moves

Through an Avonmore winter, warm humid indoor air pushes outward through the assembly. A vapour barrier on the warm side stops that moisture before it reaches a cold surface where it can condense.

Two barriers is worse than one

A second barrier on the cold side traps moisture between the two with no direction to dry. It is a genuine mistake we still find in renovated walls, and it is invisible until the damage shows.

The parts an inspector looks at first

Predictable list

Electrical boxes, seams landing off framing, the top and bottom plates, window returns and any penetration. Those are where Avonmore vapour barrier inspections fail, and they fail for the same reasons every time.

Why we sequence to it

We leave the work visible and board after the inspection rather than ahead of it. Covering something an inspector needs to see costs a wall, not an afternoon.

Renovations, and meeting an existing barrier

Continuity across old and new

In an Avonmore renovation the new poly has to tie into whatever is already in the wall. A new sheet stopped at the edge of the work leaves an open seam inside the assembly.

What we look for

Whether an existing barrier is present at all, what condition it is in, and whether there is a second one somewhere that would trap moisture between the two. Older renovations quite often have both, and finding that before boarding is worth the hour it takes.

Electrical boxes, the usual failure point

A hole in the plane

Every outlet and switch in an Avonmore exterior wall is a cut in the poly. Left unsealed it is a direct path for moist air into the cavity, and the boxes are usually the coldest spot on the wall.

Poly hats and sealant

Boxes get a poly hat or an air-sealed box, and the poly is sealed to it rather than simply cut around. It is a small detail repeated dozens of times, which is exactly why it gets skipped.

How it works

Simple, clean, on schedule — Vapour Barrier Installation in Avonmore Edmonton

Free quote

We come out to your Avonmore Edmonton property, take a real look at the vapour barrier installation, and hand you a fixed price on the spot — no guessing, no vague ballpark. Every vapour barrier installation quote in Avonmore Edmonton starts with an honest, on-site assessment.

Book a day

We pick a day that works for your schedule and show up on time, ready to start the vapour barrier installation in Avonmore Edmonton. No back-and-forth rescheduling — once it's booked, our team is there.

The work

We keep the dust under control and protect your Avonmore Edmonton home while we finish the vapour barrier installation to a clean, paint-ready standard. Floors covered, doors sealed off, and the site left tidy at the end of every day.

Walk it with you

We don't pack up till you've walked the finished vapour barrier installation with us and you're happy with the result in Avonmore Edmonton. If anything needs a second look, we handle it before we call the job done.

Reviews

Rated by Edmonton Homeowners

★ ★ ★ ★ ★

Emplastrum Drywall is the vapour barrier installation contractor Avonmore Edmonton trusts for repair, restoration and finishing — rated on Google by Edmonton homeowners.

Read the reviews, or leave your own after your vapour barrier installation project in Avonmore Edmonton.

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FAQ — Vapour Barrier Installation Avonmore Edmonton

Vapour Barrier Installation Avonmore Edmonton: your questions answered

Is the vapour barrier the same as an air barrier?: Not by itself. Poly slows vapour diffusion; sealed properly it also slows air, and unsealed it does very little of either. The sealing is what turns a sheet of plastic into a working assembly.
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.
Will this pass inspection?: It is built to what the code asks for on your permit, and we leave it visible and sequence to your inspection date rather than boarding ahead. If an inspector raises something, we want the note directly so it is fixed from the actual reason.
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.
Should I use poly or a smart membrane?: Most straightforward Avonmore 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.
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.

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Vapour Barrier Installation Avonmore Edmonton

Vapour barrier in Avonmore, sealed as a continuous plane