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 a bathroom done differently?

Same rules, larger consequences. A bathroom pushes far more vapour into the wall, so a gap shows up faster. The fan housing and duct are sealed rather than trimmed around, and we check the fan vents outside rather than into the attic.

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.

Should I use poly or a smart membrane?

Most straightforward Rosslyn 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 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.

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 Rosslyn renovations quite often have both, and finding that before boarding is worth the hour.

Vapour Barrier Installation Rosslyn Edmonton | 6 Mil Poly

Poly and air sealing in Rosslyn 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
Poly on the warm side of the insulation
Window and door returns detailed properly
Electrical boxes poly-hatted and sealed
Rim joists air-sealed before insulating
Left ready for inspection before boarding

Inspection, and leaving it visible

It gets checked before it is covered

Vapour barrier and air sealing in Rosslyn are inspected before drywall covers them. We sequence to your inspection date rather than boarding ahead and covering something the inspector needs to see.

If it does not pass

We want the inspector's note directly. Most failures are specific — an unsealed box, a floating seam, a torn return — and they are corrected faster from the actual note than from a second-hand summary.

Rosslyn drywall in context

About Rosslyn

Rosslyn, just to the northeast of the city centre, was developed during the 1950s and 60s.

What we see in Rosslyn

In Rosslyn 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.

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 Rosslyn 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.

The rim joist and the bottom plate

Two cold junctions

In an Rosslyn 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 Rosslyn 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.

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.

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

How it works

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

Free quote

We come out to your Rosslyn 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 Rosslyn 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 Rosslyn 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 Rosslyn 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 Rosslyn 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 Rosslyn 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 Rosslyn Edmonton.

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FAQ — Vapour Barrier Installation Rosslyn Edmonton

Vapour Barrier Installation Rosslyn Edmonton: your questions answered

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 a bathroom done differently?: Same rules, larger consequences. A bathroom pushes far more vapour into the wall, so a gap shows up faster. The fan housing and duct are sealed rather than trimmed around, and we check the fan vents outside rather than into the attic.
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.
Should I use poly or a smart membrane?: Most straightforward Rosslyn 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 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.
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 Rosslyn renovations quite often have both, and finding that before boarding is worth the hour.

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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 Rosslyn Edmonton

Poly and air sealing in Rosslyn before the board goes on