Does it matter where the sheet meets the ceiling and floor?

It is the whole job. Left loose at the top or bottom plate, warm air simply goes over or under a perfectly installed sheet. The junction into a vaulted ceiling is the most commonly skipped and the wettest point in the room.

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.

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.

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.

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.

Vapour Barrier Installation Webber Greens Edmonton | 6 Mil Poly

Poly and air sealing in Webber Greens 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.

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

Poly against smart membranes

Two approaches

Standard 6-mil poly is the common choice in Webber Greens and works when it is continuous and sealed. A variable-permeance membrane tightens in winter and opens in summer, giving the assembly a drying path in both directions.

When it is worth the difference

Most straightforward walls are fine with poly. Retrofits, assemblies that cannot be fully sealed and some basement details benefit from a membrane. We say which we would use and why rather than defaulting.

Webber Greens drywall in context

About Webber Greens

Webber Greens is a new neighbourhood in west Edmonton, Alberta, Canada.

What we see in Webber Greens

In Webber Greens the drywall work is first-year settling, basement dev for first owners, Level 5 over builder-grade. We confirm what your home actually needs on site, in writing, before anything starts.

Laps, and the framing member behind them

Where sheets meet

A lap needs to land on solid framing and be sealed with acoustical sealant compressed between the layers, not taped in mid-air across a cavity.

Why it fails otherwise

An unsupported lap flexes with pressure changes and the seal works loose. In an Webber Greens build the sheets are planned so that laps fall on studs rather than wherever the roll ran out.

What a vapour barrier is not

It is not an air barrier 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.

It is not a damp-proofing fix

If a Webber Greens basement has water coming through the wall, vapour control is not the answer and installing it will hide the evidence. That is a drainage and waterproofing problem, and we will say so rather than board over it.

Warm side, always

The one rule everything else follows

The barrier goes on the heated side of the insulation. In an Webber Greens 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.

Never two barriers

The trap

Poly on the room side plus a second impermeable layer behind the insulation leaves any moisture that gets in with no direction to dry.

Where it happens

Renovations, mostly. A new barrier gets added over a wall that already had a foil-faced or kraft-faced layer. We look at what is already in an Webber Greens wall before adding to it rather than assuming the cavity is bare.

Sealing at the electrical boxes

Every box is a hole

An outlet or switch on an exterior Webber Greens 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.

How it works

Simple, clean, on schedule — Vapour Barrier Installation in Webber Greens Edmonton

Free quote

We come out to your Webber Greens 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 Webber Greens 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 Webber Greens 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 Webber Greens 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 Webber Greens 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 Webber Greens 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 Webber Greens Edmonton.

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FAQ — Vapour Barrier Installation Webber Greens Edmonton

Vapour Barrier Installation Webber Greens 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.
Does it matter where the sheet meets the ceiling and floor?: It is the whole job. Left loose at the top or bottom plate, warm air simply goes over or under a perfectly installed sheet. The junction into a vaulted ceiling is the most commonly skipped and the wettest point in the room.
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.
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.
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.
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.

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Estimate only — rounded up, based on standard coverage rates (drywall +10% waste; paint ~350 sq ft per gallon per coat; batt bundles by cavity depth, less a framing factor; studs at your chosen spacing plus waste). Product coverage varies by brand — confirm quantities before buying. Ask us about the right R-value for your project.

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Vapour Barrier Installation Webber Greens Edmonton

Poly and air sealing in Webber Greens before the board goes on