Rim joist spray foam insulation in Sherwood Park is the smallest item on this site and one of the strongest returns on it. The rim joist is the band of framing where the floor structure meets the top of the foundation wall, running the whole way around the house, and in a climate with no warm spells it works against you continuously.
Nine months without a break is what makes it count
The band is a few inches tall and it is easy to dismiss on that basis. What makes it matter here is duration: the heating season runs the better part of nine months without interruption, so a leak in that band is not an occasional draught, it is a loss that runs every hour of every one of those days. Multiply a small rate by that many hours and it stops being small, which is why this detail regularly outperforms much larger and more expensive work.
Why it was never done properly in this stock
On a house from the sixties or seventies the band was treated, if at all, with a piece of batt pushed into each bay. That fills the space and leaves the joints in the framing open, so air continues to move around and behind it. It was normal practice and nobody did anything wrong. It simply does not seal, and in a suburb where most of the housing dates from that period, most of the bands are in that condition.
What actually changes in the house afterwards
The reports are specific and they are not about a number on a bill. The floor above stops being cold at the edges of the room, the strip of cold that sits along the outside walls of a finished basement goes away, and the furnace settles into longer, less frequent cycles. On a Sherwood Park house those three together are what people describe when they say the basement finally feels like part of the house.
Do it at the same time as anything else down there
It is the first thing to do in an unfinished basement and it should be done at the same time as any foundation wall work, because the access is shared and doing them separately means paying for the same setup twice. If the lower level is already finished, the band is reached by opening the top of the wall, which is a smaller job than it sounds but is no longer the cheap one.
Rim Joist Spray Foam Insulation Sherwood Park: Common Questions
How can an area as small as the rim joist matter? It is small but it leaks for nine months without a break. Duration is what makes it significant here.
Why does a rim joist with batt in it still leak air? Batt fills the bay without sealing the joints behind it. That is the usual condition and it is why the band still leaks.
When should it be done? At the same time as any other basement work, because the access is shared.
Size the assembly with the R-value calculator, then get a free Sherwood Park quote. More on Rim Joist Spray Foam Insulation Alberta.