Why is there staining around my window reveals?

Usually the vapour barrier return at the window was torn or tucked rather than sealed. It is a cold junction, so condensation shows there first — often as staining or mould at the reveal.

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

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.

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 Duggan 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 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.

Vapour Barrier Installation Duggan Edmonton | 6 Mil Poly

Poly and air sealing in Duggan before the board goes on

A vapour barrier only works as a continuous plane. In Duggan the failures are almost never the sheet itself — they are the electrical boxes, the top and bottom plates, the window returns and the penetrations, where the poly is cut and not resealed.

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

Inspection, and leaving it visible

It gets checked before it is covered

Vapour barrier and air sealing in Duggan 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.

Duggan drywall in context

About Duggan

Duggan (a pioneer citizen and former mayor of Edmonton's early rival, the City of Strathcona), Duggan reflects the popular design elements of the 1960s.

What we see in Duggan

In Duggan 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.

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.

Warm side, always

The one rule everything else follows

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

Renovations, and meeting an existing barrier

Continuity across old and new

In an Duggan renovation the new poly has to tie into whatever is already in the wall. A new sheet stopped at the edge of the work leaves an open seam inside the assembly.

What we look for

Whether an existing barrier is present at all, what condition it is in, and whether there is a second one somewhere that would trap moisture between the two. Older renovations quite often have both, and finding that before boarding is worth the hour it takes.

Inspecting it before it is covered

Last chance to see it

Once board is on, an Duggan 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.

Electrical boxes, the usual failure point

A hole in the plane

Every outlet and switch in an Duggan 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.

How it works

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

Free quote

We come out to your Duggan 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 Duggan 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 Duggan 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 Duggan 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 Duggan 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 Duggan 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 Duggan Edmonton.

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FAQ — Vapour Barrier Installation Duggan Edmonton

Vapour Barrier Installation Duggan Edmonton: your questions answered

Why is there staining around my window reveals?: Usually the vapour barrier return at the window was torn or tucked rather than sealed. It is a cold junction, so condensation shows there first — often as staining or mould at the reveal.
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 Duggan renovations quite often have both, and finding that before boarding is worth the hour.
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.
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 Duggan 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 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 Duggan Edmonton

Poly and air sealing in Duggan before the board goes on