How to Fix a Drafty Window

Drafts are the quiet thieves of home comfort, quietly stealing your climate-controlled air while letting outside humidity and chill settle into your living space. A window that whistles when the wind picks up is usually suffering from failed seals or simple physical gaps that developed as the house settled over the years. Fixing this doesn't require a professional contractor or a massive renovation budget. By systematically sealing the perimeter, sash, and glass, you turn a leaky nuisance into a tight, energy-efficient barrier. Done well, this process eliminates the cold spots near your window frame and stabilizes the temperature of your entire bedroom.

1. Find Where Air Enters. Light an incense stick and slowly pass it around the edges of the window frame and sash on a windy day. Observe where the smoke plumes inward or flickers erratically to pinpoint exactly where air is entering.
2. Strip and Clean Surfaces. Wipe down the entire window track and frame with a cloth dampened in a mixture of water and mild dish soap. Remove all dust, grit, and old adhesive residue so that new seals will adhere properly.
3. Apply V-Strip Seals. Cut the V-strip to fit the vertical sides of the window sash. Peel back the adhesive and press it firmly into the track where the sash meets the frame.
4. Cushion the Bottom Sash. Apply a rubber bulb seal or foam tape to the bottom edge of the lower sash. This creates a cushion between the sash and the windowsill when the window is locked.
5. Seal Frame-to-Wall Gaps. Inspect the gap between the window frame and the wall; if you see light, use exterior-grade silicone caulk to seal it. Apply a thin, consistent bead and smooth it with a damp finger for a clean finish.
6. Insulate with Shrink Film. If the glass itself feels cold, shrink-wrap the interior frame with a clear plastic window insulation kit. Use the included double-sided tape and a hairdryer to shrink the film until it is crystal clear and tight.