Which side does the vapour barrier go on?

The warm side of the insulation. Through an Alberta winter moisture pushes outward from the heated space, and the barrier stops it before it reaches a cold surface where it can condense.

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.

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 Evansdale walls, and it stays invisible until the damage shows.

Should I use poly or a smart membrane?

Most straightforward Evansdale 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.

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.

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 Evansdale Edmonton | 6 Mil Poly

Poly and air sealing in Evansdale 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.

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

Basement walls, where the rules change

Concrete complicates it

A Evansdale basement wall can take moisture from the ground as well as from the room. That is why a poly barrier detailed the way it is on an above-grade wall can trap moisture against the concrete instead of keeping it out.

How the assembly is built

Rigid insulation or a framed cavity held off the concrete gives the wall a way to dry, with vapour control on the warm side of the insulation. Getting that order wrong is the most common reason a finished Evansdale basement smells musty.

Where the barrier meets the ceiling and the floor

The two continuous edges

A Evansdale wall barrier has to be sealed at the top plate and the bottom plate. Left loose, warm air simply goes over or under a perfectly installed sheet.

Cathedral and vaulted areas

Where a wall runs into a vaulted ceiling the junction is awkward and often skipped. It is also the warmest, wettest point in the room because that is where the air collects. It gets detailed properly or the rest of the sheet is decorative.

The rim joist and the bottom plate

Two cold junctions

In an Evansdale basement the rim joist and the bottom plate against concrete are where warm air meets cold most directly. Both need sealing before insulation, not after.

Sequencing

Once the insulation and poly are on, neither can be reached without pulling the wall apart. We deal with them first, and we would rather flag a problem there at the quote than discover it behind a finished wall.

Seams belong on framing

Not floating in a bay

A lap sealed in the middle of a cavity has nothing solid behind it. Any movement or pressure opens it, and it cannot be inspected properly.

How we run it

Sheets are sized so seams land on a stud or plate, lapped, and sealed against solid backing. It uses slightly more material and it is the difference between a barrier that holds and one that is only continuous on the day it was installed.

Inspecting it before it is covered

Last chance to see it

Once board is on, an Evansdale vapour barrier is inaccessible for the life of the wall.

How we work

The barrier gets walked and repaired, every box, every lap, every penetration, before boarding is scheduled, and it is photographed. A tear found before the board goes on costs a piece of tape; found afterwards it costs a wall.

Windows, doors and the returns around them

Where the detail gets fiddly

The return between a window frame and the wall in Evansdale is awkward, tight, and often left as a torn edge tucked behind trim.

Why it matters

It is also a cold junction where condensation shows first, usually as staining or mould at the reveal. The poly is cut to fit, sealed to the frame and supported, rather than folded and hoped for.

How it works

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

Free quote

We come out to your Evansdale 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 Evansdale 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 Evansdale 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 Evansdale 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 Evansdale Edmonton. If anything needs a second look, we handle it before we call the job done.

Reviews

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Emplastrum Drywall is the vapour barrier installation contractor Evansdale 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 Evansdale Edmonton.

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FAQ — Vapour Barrier Installation Evansdale Edmonton

Vapour Barrier Installation Evansdale Edmonton: your questions answered

Which side does the vapour barrier go on?: The warm side of the insulation. Through an Alberta winter moisture pushes outward from the heated space, and the barrier stops it before it reaches a cold surface where it can condense.
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.
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 Evansdale walls, and it stays invisible until the damage shows.
Should I use poly or a smart membrane?: Most straightforward Evansdale 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.
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.
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 Evansdale Edmonton

Poly and air sealing in Evansdale before the board goes on