Ever wonder why your floors feel cold in January even after you've insulated the attic? The rim joist is probably the culprit โ and most Northeast Arkansas homes built before 2010 have zero insulation there.
The rim joist is the short band of framing that sits on top of your foundation wall and supports your floor system. In a typical 1,500 SF ranch home, that band adds up to 50โ80 linear feet of raw, uninsulated wood exposed to outside air. Cold air pours through gaps, sill plates, and masonry cracks all winter long.
The fix is 2" of closed-cell spray foam applied directly to the rim joist cavity. Two inches gets you to roughly R-13, which meets IRC R402.1 requirements for Climate Zone 3 โ where Jonesboro and Trumann both land. Because closed-cell foam air-seals AND insulates in one step, you eliminate the convective loop that makes batt insulation in rim joists nearly useless.
Cost? Expect $1.50โ$2.50 per board foot installed. A typical ranch rim joist job runs $300โ$600 total โ one of the best dollar-per-dollar upgrades you can make before heating season hits in October. Payback on energy savings alone is often under three years.
If your HVAC runs longer than it should on a cold January morning, or you've got that classic "cold socks" feeling walking on hardwood floors, call us before the temperatures drop. We're scheduling fall rim joist and basement work now across Craighead, Poinsett, and Greene counties.
Reply here or DM us for a free estimate โ takes about 20 minutes on-site and we can usually get you on the schedule within a week.