About 60 percent of homes in Innisfail were built before 1991, and on a roof of that age the attic problem is almost never in the middle of the attic. It is at the edge. Attic spray foam insulation in Innisfail is mostly work in the first metre or so above the exterior wall, where the rafter meets the top plate and where the snow outside decides what happens.
Wet snow is a different load from dry snow
Parkland snow arrives heavy and wet and it does not blow off a roof the way prairie snow does. It sits, it compacts, and when the temperature swings above freezing it melts from underneath against a roof deck that is being warmed from inside. The water runs down to the eave, reaches the part of the roof that is genuinely cold because there is no heated room beneath it, and freezes there. That ridge of ice then dams the next melt behind it. Everything people describe as an ice problem on an Innisfail roof is really a heat problem a few feet uphill of where the ice appears.
The heel is the reason the edge stays warm
On an older house the rafter sits more or less directly on the top plate, so the space available for insulation tapers to nothing right where it is needed most. Whatever depth was blown in got pushed back from the edge, or it was blown against the sheathing and choked the vent path. Either way the last stretch of roof deck above the wall is warmer than the rest of the roof, which is exactly the condition that produces the melt. Adding more depth in the open middle of the attic does nothing about this, because the middle was never the problem.
What foam does at the edge that nothing else does
Closed-cell foam gives roughly R-6 to R-7 per inch and becomes a vapour barrier at around two inches, which is what lets it work in a space where there is no room for depth. Sprayed into the taper, it seals the top plate, the gap behind the exterior wall sheathing and the joint between the plate and the rafter in one pass, then carries an R-value in the few inches that are actually available. With a baffle set first, the vent path stays open above it. That combination is the fix for a cold edge, and it is not achievable with material that has to be cut to a size.
Three vent systems arguing with each other
A pre-1991 roof around here has usually been re-shingled more than once, and each time somebody added ventilation. We open attics with a ridge vent, a row of roof-mounted pots and a pair of gable louvres all working at once. That is not three times the ventilation. It is a set of short circuits that pull air between the roof openings instead of from the soffit to the ridge, leaving the eaves dead and the edge warm. Deciding what to close is part of the job.
Frost on the sheathing, and where it goes in a chinook
When indoor air leaks into a cold attic the moisture it carries freezes onto the underside of the sheathing rather than showing up as a drip. It can sit there for weeks. Then the weather turns, the frost melts all at once, and it lands on the insulation and the ceiling below. Homeowners report it as a roof leak because it arrives like one. Sealing the ceiling plane is what stops it, and in this climate the thaw cycle is frequent enough that the same assembly gets loaded and unloaded several times a winter.
We take care of the work
We quote the job, schedule it and stand behind it, and our own installers do the work on attic spray foam insulation Innisfail. You deal with us from the first site visit to the last pass of foam.
Attic Spray Foam Insulation Innisfail: Common Questions
Why does the ice always build up at the gutter line? Because the melt is happening further up the roof where the deck is warm, then refreezing at the edge where the deck is cold. The ice is the symptom and the warm part is the cause.
We added more blown-in and nothing changed. Why? New depth goes on top of the open flat area, which is where the attic already worked. If the heat is escaping at the top plate and the eave, depth in the middle cannot reach it.
Can you insulate right out to the edge? With a baffle in place and closed-cell sprayed into the taper, yes. That is the one assembly that fits an R-value into a space a few inches deep.
How much does attic spray foam insulation cost in Innisfail? The sprayed portion is priced per board foot at the thickness the taper allows, with any blown-in depth over the open area on top, so the number follows area and target R-value. On this stock the small sealed area at the perimeter is where the money does the work.
How do I choose an attic spray foam contractor in Innisfail? Ask what they intend to do at the eave, and ask them to tell you which of your existing roof vents they would close. A quote that only measures the flat area has not looked at the part that is failing.
Size the job with the R-value calculator, then get a free Innisfail quote. More on Attic Spray Foam Insulation Alberta province-wide.