Ever wonder why your floors feel cold in January even with the heat cranked up? The rim joist โ that band of framing sitting right on top of your foundation wall โ is almost always the culprit. It's one of the most under-insulated spots in Northeast Arkansas homes, and it's costing you money every single day.
A typical uninsulated rim joist loses more conditioned air per linear foot than almost any other building cavity. We're talking gaps, cracks, and raw wood exposed to outside temps that regularly hit the low teens in Jonesboro and Trumann during a hard January. IRC Section R402.1 requires continuous air barriers in this zone โ but thousands of older homes were built before that code existed.
The fix is straightforward: two inches of closed-cell spray foam applied directly to the rim joist delivers roughly R-13, seals every crack in one pass, and is vapor-impermeable โ critical in a mixed-humid climate like Climate Zone 4 (where most of NEA sits). Installed cost typically runs $1.50โ$2.50 per square foot of rim joist area, and most crawl-accessible jobs wrap up in a single morning.
For a 1,500 SF ranch home with a 160-linear-foot perimeter, you're usually looking at 160โ200 board feet of foam and a finished job under $400โ$600 in most cases. Homeowners routinely report noticing warmer floors within the first heating season โ no exaggeration.
If you haven't had your rim joist looked at, it's worth a quick inspection before we hit August heat and you start thinking about next winter. We do free estimates across Craighead, Poinsett, and Greene counties.
Reply to this post, DM us, or call the number in our bio to schedule your free rim joist inspection today.