Ever wonder why your floors feel cold even after you've insulated the attic? The rim joist โ that band of framing sitting right on top of your foundation wall โ is almost certainly the culprit. It's one of the most overlooked air-leakage points in any house, and in Northeast Arkansas, where October nights are already dropping into the low 40s, it's working against you right now.
A typical uninsulated rim joist loses heat through three mechanisms at once: conduction through the wood, convection from air gaps, and moisture infiltration from the crawl space or basement below. Sealing and insulating this area with 2-inch closed-cell spray foam hits roughly R-13 in a space that previously sat at R-0. IRC R402.1.2 actually requires rim joists to be insulated in Climate Zone 3 โ where Jonesboro and Trumann both land โ and a lot of older homes simply never got the memo.
The job itself is fast. A typical 1,500 SF footprint house has somewhere between 150โ200 linear feet of rim joist. At roughly 1.5โ2 board feet of foam per linear foot, most rim joist jobs run $1.50โ$2.50 per square foot of wall surface โ often under $600 total. Homeowners regularly report a noticeable difference in floor comfort and HVAC run-time within the first heating cycle after the work is done.
If your energy bills have crept up and your attic already has adequate insulation, the rim joist is the next place to look. It's a small investment with a disproportionately big payoff โ especially heading into a Jonesboro winter.
Reply or DM us for a free rim joist assessment. We serve Jonesboro, Trumann, Paragould, and the surrounding Northeast Arkansas area.