Rim joist insulation might be the most overlooked energy leak in Northeast Arkansas homes. These wooden boards sit between your foundation and first floor, creating a thermal bridge that can waste 10-15% of your heating and cooling costs.
Most rim joists in our area are completely uninsulated or stuffed with old fiberglass that's pulled away from the wood. This creates air gaps where your conditioned air escapes and humid outdoor air sneaks in — especially brutal during our 90°F summers and surprise February freezes.
Closed-cell spray foam is the gold standard for rim joist sealing. At R-6 per inch, two inches gives you R-12 while creating an air barrier that fiberglass can't match. For a typical 1,800 SF home, you're looking at roughly $800-1,200 for professional spray foam application.
The payback is solid. Most homeowners see 8-12% reduction in energy bills, which translates to $150-250 annual savings. In Jonesboro's climate zone, rim joist insulation typically pays for itself in 4-6 years.
DIY foam boards can work too, but getting a perfect air seal around all the pipes, wires, and irregular spaces is tricky. Gaps defeat the purpose.
With summer electric bills climbing, now's a smart time to tackle this project before peak cooling season hits. Your HVAC system will thank you when it's not fighting to maintain 72°F against rim joist air leaks.
Thinking about rim joist insulation for your home? Reply or DM us for a free estimate.