WHERE TO USE

RIM JOIST

The rim joist supports the floor joists and is located in the area where the wall meets the basement ceiling. Since clapboard siding typically ends here, it is a major source of air infiltration. In fact, a recent study conducted by Dow revealed that by sealing sill plate/rim joist penetrations, homeowners can save $44 annually.**

If fiberglass insulation is already installed, remove the insulation and use GREAT STUFF™ Gaps & Cracks to seal the intersecting edges of the rim joist, wall and floor joists. Then replace the insulation once the foam has cured. If there is no insulation, install some now. Or, better yet, cut pieces of foam board like blue STYROFOAM™ Brand Extruded Polystyrene (XPS) Foam Insulation up to 2 inches thick or THERMAX™ Insulation up to 4 inches thick to fit in each rim joist "box." Then use GREAT STUFF™ Gaps & Cracks to seal around the four edges of the foam board.

** In this study, air loss was measured using blower door tests. Potential energy savings were estimated using REM Home Energy Analysis Software. Results vary based on construction, style, year built and other unique home characteristics. Participating homeowners were current employees of Dow.