What if there is already a vapour barrier in the wall?

We tie into it, and we check whether there is a second one somewhere that would trap moisture between the two. Older Glastonbury renovations quite often have both, and finding that before boarding is worth the hour.

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

Should I use poly or a smart membrane?

Most straightforward Glastonbury 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.

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.

Can you install the barrier if someone else did the insulation?

Yes, but we check the insulation first. A barrier over a poorly filled cavity locks the problem in, and once the board is on neither can be corrected without opening the wall.

Vapour Barrier Installation Glastonbury Edmonton | 6 Mil Poly

Poly and air sealing in Glastonbury 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.

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

Poly against smart membranes

Two approaches

Standard 6-mil poly is the common choice in Glastonbury 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.

Glastonbury drywall in context

About Glastonbury

Glastonbury is named after an English monastery that is associated with the legend of King Arthur and the location of the Holy Grail.

What we see in Glastonbury

In Glastonbury 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.

The rim joist and the bottom plate

Two cold junctions

In an Glastonbury 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.

Warm side, always

The one rule everything else follows

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

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 Glastonbury 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.

Inspecting it before it is covered

Last chance to see it

Once board is on, an Glastonbury 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.

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 Glastonbury wall before adding to it rather than assuming the cavity is bare.

How it works

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

Free quote

We come out to your Glastonbury 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 Glastonbury 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 Glastonbury 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 Glastonbury 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 Glastonbury 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 Glastonbury 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 Glastonbury Edmonton.

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FAQ — Vapour Barrier Installation Glastonbury Edmonton

Vapour Barrier Installation Glastonbury Edmonton: your questions answered

What if there is already a vapour barrier in the wall?: We tie into it, and we check whether there is a second one somewhere that would trap moisture between the two. Older Glastonbury renovations quite often have both, and finding that before boarding is worth the hour.
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 Glastonbury walls, and it stays invisible until the damage shows.
Should I use poly or a smart membrane?: Most straightforward Glastonbury 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.
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.
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.
Can you install the barrier if someone else did the insulation?: Yes, but we check the insulation first. A barrier over a poorly filled cavity locks the problem in, and once the board is on neither can be corrected without opening the wall.

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Vapour Barrier Installation Glastonbury Edmonton

Poly and air sealing in Glastonbury before the board goes on