Drafty windows and doors can cost you hundreds in energy bills each year. If your home feels chilly during winter or struggles to stay cool in summer, it’s time to address those leaks. Fixing drafts doesn’t require a contractor. With a few tools and techniques, you can seal gaps effectively and improve your home’s energy efficiency.

Identifying Drafts: Where to Start

Before applying fixes, locate the problem areas. Common culprits include window frames, door edges, and gaps around vents. To pinpoint drafts, try the candle test.

Light a candle and move it along suspected draft points. If the flame flickers, you’ve found a leak. Another option is the incense test: smoke trails will drift toward the gap. Don’t forget attic hatches and basement doors, they’re often overlooked but can cause significant energy loss.

Pro tip: A thermal camera can identify even minor leaks. Budget models start at $150, or you can rent one at Home Depot for under $50/day.

Check weatherstripping around doors. If it’s cracked or flattened, it won’t seal properly. For windows, look at the caulking. Deteriorated caulk leads to gaps that let cold air in. For larger gaps, inspect structural elements like siding or flashing.

Learn more about home insulation techniques to further reduce energy loss and improve comfort.

Fixing Drafty Windows

Windows are a major source of heat loss. Fixing them is often straightforward. Start with weatherstripping. Foam tape, available for $5-$10 a roll, is easy to apply and works well for double-hung windows. Clean the surface first, then press the tape along the edges. This creates a tight seal when the window is closed.

For sliding or casement windows, consider silicone weatherstripping or V-strips. These cost $10-$25 per pack and are durable enough for frequent use. If your window frames allow, you might also add draft blockers, long fabric tubes filled with foam or sand, placed along the bottom edge.

Caulking is another essential step. Use a high-quality silicone caulk, like GE Silicone II ($8 for a tube), to seal gaps outside the window frames. Apply it smoothly with a caulking gun. Wait 24 hours for it to cure fully.

If the glass pane itself feels cold, it’s time to upgrade. Look for double- or triple-pane windows with low-E coatings. These can cost $300-$1,000 per window, but they significantly reduce heat transfer and improve insulation.

Explore caulking and sealing tips for more detailed instructions.

Fixing Drafty Doors

Doors are another common source of energy loss. Start by checking the door sweep, the piece attached to the bottom of the door. If you see daylight under the door or feel air moving, replace the sweep. A new rubber or silicone sweep costs $10-$20 and installs easily with screws or adhesive.

For gaps along the sides or top of the door frame, use weatherstripping. Adhesive foam tape works for small gaps, while rubber or vinyl strips are better for larger ones. Expect to spend $15-$40 depending on the material and length.

Don’t forget the door threshold. If it’s worn, air can seep through. Adjustable thresholds are available for $20-$50 and can be tightened to close gaps. For doors that are especially drafty, a draft stopper may be necessary. These cost $10-$30 and can be placed at the bottom to block airflow.

Sliding glass doors require attention to the tracks. Vacuum out dirt and debris and add weatherstripping to any gaps. For an extra layer of protection, consider thermal curtains ($20-$100) to reduce heat loss.

Compare air purifiers and dehumidifiers to complement your draft-proofing efforts.

Insulating Around Windows and Doors

Insulation is critical for long-term energy savings. Start with expanding foam sealant, such as Great Stuff ($5-$15 per can). Spray it into larger gaps around window and door frames. It expands to seal spaces effectively and hardens within hours.

For older homes, adding rigid foam insulation panels around window frames can help. Products like Owens Corning Foamular ($30 for a 2’ x 8’ sheet) provide excellent thermal resistance.

Another option is window insulation film. This clear plastic sheet adheres to the inside of windows, creating an extra layer of insulation. Kits cost $10-$25 and can reduce heat loss by up to 20%. Apply the film with a hairdryer for a smooth finish.

Reflective insulation is ideal for sunny areas. Brands like Reflectix ($20 for a roll) help block solar heat gain during summer. Install them on windows facing direct sunlight.

If your home has older or single-pane windows, consider replacing them with energy-efficient models. Energy Star-rated windows can cut utility bills by 12%, according to the EPA.

FAQ

How do I test for drafts without special tools?

Use the candle test. Light a candle and move it along edges of windows, doors, and vents. If the flame flickers, you’ve found a draft. You can also use your hand to feel for cool air or hang a lightweight curtain to see if it moves.

Can I use duct tape to seal window drafts in an emergency?

Yes, duct tape can work temporarily to block drafts. It costs around $5-$10 per roll and is easy to apply. However, it’s not a long-term solution. The adhesive may damage paint or finishes over time and will likely need frequent replacement.

What’s the best way to seal large gaps in windows?

For large gaps, use expanding foam sealant like Great Stuff ($5-$15 per can). Spray it into the gap, and it will expand to fill the space. Once cured, trim any excess for a clean look. For gaps larger than 1 inch, consider professional repair.

Are thermal curtains worth the investment?

Absolutely. Thermal curtains can reduce heat loss by up to 25%, according to the U.S. Department of Energy. They cost $20-$100 per panel and can also block sunlight during summer, keeping your home cooler.

Should I replace my windows if they’re drafty?

If the frames are intact, try weatherstripping and caulking first. For single-pane windows or those with cracked glass, replacement is often the best option. Energy-efficient windows cost $300-$1,000 each and can save $125-$465 annually.