What about outlets on exterior walls?

Each one is a deliberate hole. They need poly hats or airtight boxes sealed to the sheet. Taping poly to the front of an ordinary box does not last once board is fastened over it, and it is the most common leak we find.

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.

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.

Will this pass inspection?

It is built to what the code asks for on your permit, and we leave it visible and sequence to your inspection date rather than boarding ahead. If an inspector raises something, we want the note directly so it is fixed from the actual reason.

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

Vapour Barrier Installation Morinville | 6 Mil Poly

Poly and air sealing in Morinville before the board goes on

A vapour barrier only works as a continuous plane. In Morinville 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.

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

Warm side, always

The one rule everything else follows

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

Basement walls, where the rules change

Concrete complicates it

A Morinville 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 Morinville basement smells musty.

The rim joist and the bottom plate

Two cold junctions

In an Morinville 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.

Windows, doors and the returns around them

Where the detail gets fiddly

The return between a window frame and the wall in Morinville 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.

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

Inspection, and leaving it visible

It gets checked before it is covered

Vapour barrier and air sealing in Morinville 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.

How it works

Simple, clean, on schedule — Vapour Barrier Installation in Morinville

Free quote

We come out to your Morinville 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 Morinville 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 Morinville. No back-and-forth rescheduling — once it's booked, our team is there.

The work

We keep the dust under control and protect your Morinville 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 Morinville. If anything needs a second look, we handle it before we call the job done.

Reviews

Rated by Morinville Homeowners

★ ★ ★ ★ ★

Emplastrum Drywall is the vapour barrier installation contractor Morinville trusts for repair, restoration and finishing — rated on Google by Morinville homeowners.

Read the reviews, or leave your own after your vapour barrier installation project in Morinville.

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FAQ — Vapour Barrier Installation Morinville

Vapour Barrier Installation Morinville: your questions answered

What about outlets on exterior walls?: Each one is a deliberate hole. They need poly hats or airtight boxes sealed to the sheet. Taping poly to the front of an ordinary box does not last once board is fastened over it, and it is the most common leak we find.
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.
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.
Will this pass inspection?: It is built to what the code asks for on your permit, and we leave it visible and sequence to your inspection date rather than boarding ahead. If an inspector raises something, we want the note directly so it is fixed from the actual reason.
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 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 Morinville walls, and it stays invisible until the damage shows.

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Vapour Barrier Installation Morinville

Poly and air sealing in Morinville before the board goes on