Leaky windows are almost always the result of dried out caulking. Caulking is supposed to last many years, but if it is exposed to direct sunlight year after year, it can lose its protective qualities. It shrinks, pulls away from the glass or wood and actually creates a channel that funnels water right into your home. The only sure-fire way to stop windows from leaking air and water is to remove the old material and replace it with some fresh caulking.
Pry at one corner of the dry caulking with a caulk removal tool. When the edge comes loose, insert the edge of the tool behind the caulk and run the tool down the side of the window to cut the dry caulking away from the window. Do all sides where the glass touches the window, and the perimeter of the casing where the window touches the brick or siding. Pry and scrape off any remaining caulking with the tool. Use a wire brush to scrape out any remaining debris from cracks or openings where the old caulk came out.
Remove extremely difficult caulk with an oscillating tool equipped with a flexible scraper blade accessory. As caulk ages, it can become really hard and difficult to remove by hand. Use the oscillating tool to tackle these tough areas. The oscillating tool makes quick work of any type of caulk removal.
Hammer nails or small brads into any loose trim pieces, molding or braces around or on the window.
Insert fresh caulk into the applicator and clip off the end. Starting at the top, liberally apply a heavy bead of caulk to the same places where the old caulk came out. Pull the trigger as you move the applicator down the sides, along the top and bottom of the window to replace any old caulking. If you see any new cracks or splits, fill them with caulk.
Apply caulk to any new nail holes, dips, chips, gouges, splits or cracks. Let the caulking dry for 24 hours before using the window.
Tips & Warnings
- There are many colors of caulking. Purchase one that best matches your siding.
- Don't pry too hard on old glass or get too rough with it. It can be fragile.
- Use protective eye wear when using power tools.
Things You'll Need:
- Caulk removal tool
- Oscillating tool
- Flexible scraper blade accessory
- Nails or brads
- Exterior caulk
- Caulk applicator
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