Ever wonder why your floors feel cold in January even after you insulated the attic? Chances are your rim joists are bare โ and they're bleeding conditioned air 24/7.
The rim joist is the band of framing that sits right on top of your foundation wall, running the entire perimeter of your home. In most Northeast Arkansas houses built before 2010, it's either uninsulated or stuffed with old fiberglass batts that have sagged, shifted, and lost half their R-value. IRC Section R402.1 requires rim joists to hit R-15 minimum in Climate Zone 3 โ a target that droopy batts rarely meet.
Closed-cell spray foam is the gold-standard fix here. A 2-inch lift of 2-lb closed-cell foam hits R-13 to R-14 and โ more importantly โ air-seals the cavity completely. Mice, moisture, and July humidity all find their way in through rim joists; foam stops all three at once. Material cost typically runs $1.75โ$2.50 per board foot installed, and an average 1,500 SF ranch home has roughly 150โ200 lineal feet of rim joist, meaning most jobs come in under $1,200.
In Jonesboro and Trumann, summer humidity is just as brutal as winter cold. An air-sealed rim joist keeps that muggy June air out of your crawl space and subfloor, which protects wood from long-term rot and keeps your AC from working overtime.
This is one of those quick-turnaround jobs โ most rim joist installs take half a day โ with payback periods well under five years based on typical utility savings of 10โ15% on heating and cooling.
Reply or DM us for a free rim joist inspection and estimate. We serve Jonesboro, Trumann, Paragould, and surrounding Northeast Arkansas communities.