Rim joist spray foam insulation in Picture Butte is the smallest item we quote and consistently the one owners here notice most for what it involves. The rim joist is the band of framing where the floor structure sits down on top of the foundation wall. It runs the entire perimeter of the house, it is roughly the depth of a floor joist, and in most houses in this town it has never been touched.
The drift line and the rim joist line are the same line
Here is the local reason it matters more than the usual explanation suggests. On open ground with little to break the wind, snow does not stay where it falls; it moves and it piles against anything standing up. The foundation wall of a house is exactly that, so by January there is a drift packed against it on the exposed sides.
Most people assume a drift insulates. It does, where it is actually covering the wall. The problem is the top edge of it. Snow packed against a wall channels wind along its surface and concentrates it right at the line where the drift ends, and on most houses in this town that line sits at or just above the top of the foundation - which is the rim joist. So the one band of the building with the least insulation in it is also the band getting the most air movement across it in the coldest weeks of the year.
That is why the complaint is nearly always the same: the floor is cold along the outside walls, and it is worse on windy days than on merely cold ones.
What is in there now
In almost every house of this vintage, a piece of fibre batt pushed into each joist bay by hand. It was never sealed, it does not fit the irregular space, and in many bays it has slumped out of position. Behind and around it the gaps are continuous: between the sill plate and the concrete, at the ends of each joist, and wherever a service passes through.
Batt in that location does very little, because the problem is air movement and batt does not stop air. That is the single most useful thing to understand about this job. The foam is bought as an air seal that happens also to insulate, not the other way round.
Why foam fits this particular space
Each joist bay is a slightly different shape, with the joist end, the sill plate, the concrete and sometimes a service all meeting in a corner. Nothing cut to size will seal it. Closed-cell foam is sprayed into the bay, expands into every gap, bonds to the wood and the concrete, and at roughly two inches is a vapour retarder as well, which is what it needs to be against an exterior band like this.
It is also the easiest job in the house to carry out. It happens inside the basement, usually from a ladder, and it disturbs no finished room. Where the basement is unfinished, the whole perimeter is reachable in a single visit.
What changes afterwards
Two things that owners report consistently. The floor along the outside walls stops feeling cold, which in a bungalow is most of the floor area people actually walk on. And the difference between a calm cold day and a windy cold day shrinks, because the band that was responding to the wind has been closed.
Who you are dealing with
Rim joist spray foam insulation Picture Butte is work we take care of ourselves. We scope it, we quote it, we schedule it, and our own installers are the ones holding the gun.
Rim Joist Spray Foam Insulation Picture Butte: Common Questions
Why is my floor colder on windy days than on cold ones? Because the rim joist is an air leak rather than just a thin spot. Wind drives air through it, and the floor directly above responds within minutes.
There is batt in there already. Is that not enough? No. The rim joist problem is air movement and batt does not stop air. It also rarely fits the bay well enough to be doing much thermally.
How much does rim joist spray foam insulation cost in Picture Butte? Priced per board foot over the area sprayed, and the total area is small, which is why this item recovers its cost faster than anything else we quote. Access along the perimeter is the only real variable.
Best rim joist spray foam insulation contractor in Picture Butte? Ask whether they seal the sill plate to the concrete as part of it. The joint between the wood and the foundation is where a lot of the leak actually is.
Size the assembly with the R-value calculator, then get a free Picture Butte quote. More on Rim Joist Spray Foam Insulation Alberta province-wide.