Air Sealing Checklist
- Seal bottom plate of exterior walls with caulk or gasket; seal inside edge with caulk after walls are up.
- Seal band joist with caulk, spray foam, or gasketing between top plate and band joist, and between band joist and subfloor.
- For bath tubs on outside walls, insulate the exterior wall and air seal behind tub with sheet goods or plastic before tub is installed. After the drain is installed, seal the tub drain penetration with sheet goods and caulk or spray foam.
- For droped ceilings or soffits, duct and flue chases, and open partition walls, use sheet goods and sealant to stop air leakage from attic into soffit and then insulate. Alternately, install framing and drywall for the soffits after the taped ceiling drywall is installed.
- Caulk the backsides of window flanges to the sheathing during installation.
- Seal between door thresholds and subflooring with caulk.
- Seal window and exterior door rough openings with backer rod and caulk, or use non-expanding latex-based spray foams that will not pinch jambs or void window warranties.
- Seal all electrical wire, plumbing, and HVAC penetrations between any conditioned and unconditioned spaces with caulk or spray foam.
- Seal wiring and knockouts in electrical boxes with caulk. Also seal outdoormounted boxes to the exterior sheathing.
- Seal drywall to top and bottom plates using gaskets, adhesive, or caulk.
- Seal electrical switch, outlet, and circuit breaker boxes to drywall with caulk or foam.
- Seal light fixture boxes, medicine cabinets, and bath and kitchen ventilation fans to drywall with caulk or foam.
- Seal all duct boots to floor or drywall with caulk, foam, or mastic.
- Seal any plumbing or electrical wire penetration through drywall with caulk or foam.
- Seal gaps at whole house fan with spray foam or housewrap tape (ensure louvers function properly).
- For attic hatches and kneewall accessm doors, weatherstrip and include a tight latch. Add rigid insulation.
- For attic pull-down stairs, make stairs airtight using latch bolts and weatherstripping. Add an insulated cover.
- Seal between a masonry chimney and the attic framing using sheet metal or other noncombustible sheet goods and high-temperature (450°F), fire-rated caulk.
- Seal around the metal flue of combustion equipment using a UL-approved metal collar and high-temperature (450°F), fire-rated caulk.
- Use only UL-approved airtight, IC-rated recessed light fixtures (that meet ASTM E283 requirements); seal between fixture and drywall with caulk.
AIR SEAL EXTERIOR
- Repair any damaged sheathing pieces.
- Seal all exterior penetrations, such as porch light fixtures, phone, security, cable and electric service holes, with caulk or spray foam.
- If not using housewrap, seal all sheathing seams with housewrap tape or caulk.