How to Seal Drafty Windows and Doors

Feeling a chilly breeze indoors even when all the windows are closed? That likely means you’re dealing with drafty windows or doors. Not only do drafts make your home uncomfortable, but they also cause your heating and cooling systems to work overtime leading to higher energy bills. The good news? You can fix most drafts yourself. This guide will show you exactly how to seal drafty windows and doors with simple tools and techniques, helping you stay warm, save money, and improve your home’s energy efficiency.

Why Sealing Drafts Matters

Drafts are one of the biggest culprits behind heat loss in winter and cool air loss in summer. According to the U.S. Department of Energy, sealing air leaks around windows and doors can reduce heating and cooling costs by up to 20%. That means learning how to seal drafty windows is not just a comfort issue it’s a smart move for your wallet and the environment.

How to Identify Drafts in Your Home

Before you can fix the problem, you need to know where the cold air is coming from. Here are some easy ways to detect drafts:

1. Feel for Cold Spots

Move your hand slowly around the edges of doors and windows. A sudden drop in temperature or airflow usually means there’s a gap.

2. Use the Candle or Incense Test

Light a candle or stick of incense and move it around window frames and door edges. If the flame flickers or the smoke trails sideways, there’s a draft.

3. Check for Daylight

Look around your door frames if you can see light coming through the edges, air is definitely getting through too.

4. Inspect During Windy Weather

Drafts are often most noticeable on windy days. This is a great time to walk around and do a visual and tactile check.

Tools and Materials You’ll Need

Before you begin sealing drafts, gather these DIY essentials:

• Weatherstripping (foam, rubber, or vinyl)

• Caulk and caulk gun (for cracks and gaps)

• Door sweeps or draft stoppers

• Expanding foam sealant (for large gaps)

• Plastic film insulation kits (for windows)

• Scissors, measuring tape, utility knife, and gloves

Most of these items are affordable and available at any hardware store.

Guide to Sealing Drafts

Now let’s walk through how to fix drafty doors and windows using practical, DIY-friendly steps.

1. Sealing Drafty Windows

a. Apply Weatherstripping

Clean the window frame and measure the length of the sides and top. Cut the weatherstripping to size and press it firmly into place around the window sash to create a tight seal when closed.

b. Caulk Around the Frame

Use a caulk gun to seal any visible cracks where the window frame meets the wall. Choose exterior-grade caulk for outside windows and paintable interior caulk for inside use.

c. Use Plastic Film Window Insulation

For older, single-pane windows, plastic film kits can significantly reduce heat loss. Simply attach the film with double-sided tape and shrink it using a hairdryer for a snug fit.

d. Close Gaps With Foam Sealant

For large gaps or cracks in the window frame or casing, spray expanding foam sealant into the crevices. Be cautious this foam expands a lot.

2. Sealing Drafty Doors

a. Install Weatherstripping Around the Frame

Apply adhesive-backed foam or rubber weatherstripping around the door jamb to eliminate side and top drafts.

b. Add a Door Sweep

Door sweeps attach to the bottom of the door and block air from sneaking in underneath. Choose from adhesive, screw-on, or slide-in models.

c. Use Draft Stoppers

For a temporary or renter-friendly fix, place a fabric or weighted draft stopper (aka draft snake) along the bottom of the door.

d. Check the Threshold

Sometimes the threshold needs adjusting. Tighten screws to raise the threshold, or add a door seal gasket to close gaps.

Temporary Fixes for Renters

If you’re renting and need non-permanent solutions, try these:

• Removable weatherstripping (adhesive foam tape)

• Draft snakes for both windows and doors

• Plastic film window kits

• Tension rods with thermal curtains to block drafts

These fixes can be removed when you move without damaging the property.

When to Call a Professional

Some issues are best left to the experts. Consider hiring a pro if:

• You notice significant water damage or rotting around windows or doors

• Your windows are very old or warped and need replacing

• There’s noticeable condensation or fogging between window panes (a sign of broken seals)

• DIY fixes don’t improve comfort or energy efficiency

While learning how to seal drafty windows is great for minor leaks, sometimes full replacements or structural repairs are the better long-term investment.

Conclusion

Drafty windows and doors may seem like a small annoyance, but they can have a big impact on your comfort and energy bills. With a few basic tools and a little time, you can weatherproof your home and enjoy a cozier, more efficient living space.