Is Your Home Leaking Air?

Older homes were Drafty and could naturally ventilate themselves. Modern homes are designed to be more air tight and ventilation, heating and cooling are more controlled. Sealing air leaks now makes your home more comfortable and helps reduce heating and cooling costs.

Sealing air leaks is one of the most cost-effective ways to improve energy efficiency, reduce heating and cooling bills (potentially saving 10-20% on energy costs), eliminate drafts, and enhance indoor comfort. Uncontrolled air leakage can account for significant energy loss, as conditioned air escapes and outdoor air infiltrates. Many leaks are hidden, but DIY methods can address the most common ones.

Finding Air Leaks

Before sealing, identify leaks:

Visual and tactile inspection: Check for daylight around doors/windows, cracks in walls, or rattling frames.

Incense or candle test: On a windy day, hold lit incense near suspected areas—if smoke blows horizontally, there's a leak.

Hand test: Feel for drafts around edges.

Professional option: A blower door test (often part of an energy audit) depressurizes the home to reveal leaks precisely, sometimes using infrared cameras.

Common Leak Locations

Windows and doors (frames, sills)

Electrical outlets/switches on exterior walls

Plumbing/duct/wiring penetrations

Attic hatches, Roof Vents and Penetrations, recessed lights, chimneys

Baseboards, rim joists in basement/crawlspace

Vents, fans, fireplaces

Sealing Methods and Materials

Use the right material for the job:

Caulk: For stationary cracks/gaps (e.g., window frames). Choose silicone or latex; paintable if needed.

Weatherstripping: For movable parts (doors, operable windows). Foam, V-strip, or door sweeps.

Expanding foam: For larger gaps (e.g., plumbing holes). Use low-expansion to avoid overfill.

Foam gaskets: Behind outlet/switch plates.

Other: Rigid foam or fire-rated materials for attics/chimneys.

Tips for Success

Start with easy, high-impact areas like doors/windows and outlets.

Clean surfaces before applying materials.

Don't over-seal—maintain ventilation to avoid moisture or indoor air quality issues (e.g., use exhaust fans).

For complex areas (attics, ducts), consider a professional.

Many utility companies offer rebates or free audits.

These DIY steps can yield quick payback, often within a year. If your home is older or very leaky, a full energy assessment maximizes savings.