Rim joist spray foam insulation in Morinville is the single item that appears on every house in this town regardless of which half it belongs to, and it gets there by two entirely different routes.
The same symptom arriving from opposite directions
On the older half the space where the floor structure sits on the foundation was never insulated at all, so it is an open band of cold running right around the building. On the newer half it usually has insulation in it, held in place, with nothing sealing the joint behind. Both produce cold floors at the edge of the room above and a basement that will not hold temperature near the ceiling, and both are fixed by making that band continuous rather than by adding more material to it.
Why held-in-place insulation does so little there
A batt cut and pushed into each bay stops heat crossing the material and does nothing at all about air moving around it. In this location that is the whole problem: the joint between the wood and the concrete is not airtight, the ends of the joists sit in pockets, and warm moist air from the basement reaches cold surfaces behind whatever is in the way. Foam applied to the surfaces solves both at once, which is why this detail comes up so often in a Morinville quote.
What it costs relative to what it changes
This is the least expensive item on either list here, and it is measured in a day rather than a week. The band is reachable from inside the basement, it does not involve taking a room apart, and it does not require a decision about finishes. For a household in this town wanting to spend a modest amount and feel it, this is the recommendation, and it is worth making before anybody talks about walls or attic depth.
The places along that band where it is always worse
The corners, where two runs meet and the pocket is deepest. Wherever a service passes through, which is usually several points along one elevation. Under a door threshold, where the framing steps and the detail was made on site. And anywhere an addition meets the original building, because there the band belongs to two structures that were built at different times. Those points are checked individually rather than treated as part of a run, and they are where most of the time on the job actually goes.
Rim Joist Spray Foam Insulation Morinville: Common Questions
Does this apply to a newer house? Yes. There it is usually insulated and not sealed, which produces the same cold floor.
Why not just add insulation? Because the loss is air moving around it rather than heat passing through it.
What does it involve? Access from inside the basement, usually a day, and no decisions about finishes.
Size the assembly with the R-value calculator, then get a free Morinville quote. More on Rim Joist Spray Foam Insulation Alberta.