Windows can leak both water and air. Sometimes the leaks occur because the seals around the windows have broken or pulled away due to aging or long-term exposure to harsh weather. In that case, both drafts and rain can seep into your home through the leak.
Leaks can also occur when rain gets into the house through a problematic roof, chimney, or siding that doesn’t fit snugly against the house. In that case, the water will flow down through the interior of the house until it encounters a window, and will then drip in through a window frame.
Caulk and seal
Although replacing your old windows with new ones is always a wise choice if it’s within your budget, for a short-term solution, it’s pretty simple to fix your window seals. Start with an inexpensive caulking gun from your local hardware store. Examine the window all around the frame to see if you can detect the leak. You may need to remove any old caulk and paint, which you can do with a putty knife, large screwdriver, or stiff brush. Make sure the area is dry so you don’t seal in moisture. Cut the tip of the caulking cartridge at a 45-degree angle and insert it into the dispenser or “gun.” Hold the dispenser at an angle against the window and press the trigger. You can caulk all joints in a window frame and the joint between the frame and the wall, as well as individual leaks.
While caulking works to seal up cracks and gaps on immovable parts of a window, weather stripping is used to create air-tight barriers on the movable parts of a window. There are many kinds of weather stripping to choose from, including self-stick plastic vinyl, felt, reinforced foam, tape, and metal. To narrow down your choices, consider price, visibility, and attractiveness of the stripping from both inside and outside the window, as well as the durability and ease of installation. A sales person should be able to help you make the right decision when you shop.
Ask a pro
If your windows are leaking water through the frames or sills, rain is probably getting into the house either because the exterior seals have worn away or because there are problems with the roof, chimney, spaces between siding panels, or possibly even a backed-up gutter.
A roofing contractor can inspect your roof and chimney for holes, missing shingles, poor flashing, or backed-up gutters. Sometimes you can solve the problem by replacing the shingles, patching the roof, and cleaning out the gutters. You may need to replace the flashing around the roof seams and the chimney. As an extra precaution, caulk all the way around the windows outside to make sure they’re sealed against rain.
Make minor repairs
You can also inspect your siding for loose panels. You or a contractor can hammer loose panels back into place to prevent water from getting into the house that way.
You might have to hose down the side of the house in sections until the window starts to leak and you can pinpoint the place outside where the problem is. Once you do, you can determine if siding needs to be secured or replaced.
Don’t let leaks go unattended for long. Air leaks can boost your energy bills as much as 15%, because they let hot air in during the summer, as well as cold air during winter, which puts extra strain on your HVAC system. Water leaks can also damage your interior walls and cause mold to build up on the inside of your drywall.
How have you dealt with your drafty windows? Which method worked best? Tell us about it in the comments below!