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.

Should I use poly or a smart membrane?

Most straightforward Highlands 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.

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

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.

Vapour Barrier Installation Highlands Edmonton | 6 Mil Poly

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

Top plates, bottom plates and the perimeter

The edges do the leaking

The continuous joints at the top and bottom of an Highlands wall are longer than every box and lap put together, and they are the easiest to seal well or badly.

What good looks like

Sealant on the plate, poly laid into it and compressed by the framing or the board above, carried around corners rather than cut and butted at every change of direction.

Highlands drywall in context

About Highlands

Highlands, annexed to the city in 1912, was named in a contest offering a 50-dollar prize.

What we see in Highlands

In Highlands 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.

Electrical boxes, the usual failure point

A hole in the plane

Every outlet and switch in an Highlands 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.

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 Highlands 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.

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.

Where poly is the wrong choice

Not every assembly wants it

Some Highlands walls, such as an insulated concrete basement or an assembly with exterior rigid insulation, are designed to dry inward, and a full poly layer stops that.

How we approach it

We look at the whole assembly rather than defaulting to poly because it is what is usually done. Where a smart or variable-permeance membrane is the right call, we say so.

Why the warm side, and why only one

Which way the moisture moves

Through an Highlands 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.

How it works

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

Free quote

We come out to your Highlands 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 Highlands 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 Highlands 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 Highlands 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 Highlands 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 Highlands 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 Highlands Edmonton.

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FAQ — Vapour Barrier Installation Highlands Edmonton

Vapour Barrier Installation Highlands 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.
Should I use poly or a smart membrane?: Most straightforward Highlands 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.
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 Highlands walls, and it stays invisible until the damage shows.
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.
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.

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Vapour Barrier Installation Highlands Edmonton

Poly and air sealing in Highlands before the board goes on