The rim joist - the band of framing where the floor system sits on the foundation - is the single leakiest part of most Alberta homes. It is a long run of gaps right at the cold transition between basement and outdoors, and it is usually stuffed with a scrap of batt that does almost nothing.
Why it is the best small job in the house
A rim joist retrofit is fast and cheap relative to its effect: a couple of inches of closed-cell seals the band completely, stops the draft you feel across a basement floor, and cuts the heat loss that runs all winter. It is often the highest return-per-dollar spray foam job available.
Closed-cell, every time
Because the rim joist sits at the moisture-and-cold boundary, it wants closed-cell: R-value, air-seal and a vapour barrier in one. Open-cell does not belong here.
Get a free quote - often bundled with a basement job.