Window weatherstripping 101

Benefits of weatherstripping windows

Weatherstripping can be a cheap, easy and surprisingly effective method of keeping cold air out of your warm house in the winter. Without having to be an expert at DIY, you can easily install and maintain weatherstripping without spending a fortune. Your home has a lot of different windows, all of which could be letting precious warm air out. Weatherstripping is definitely worth your time.

If your windows are in very bad shape, weatherstripping may be a waste of your time and money, however. If the frames are rotten or damaged or if the glass in the window itself is broken, you would be better off replacing the damaged windows. But once you get those issues fixed, weatherstripping can be extremely effective. Even new windows benefit from weatherstripping.

 

Where to add weatherstripping

You should target those windows that are letting in the most cold air. There are a number of ways to test this:

• Try dangling a small piece of paper in front of the window. If a draft blows the paper around, install weatherstripping there. 

• Get somebody to stand on the other side of the window while you use a hair dryer to blow air around the frame. If your helper can feel the air from the hair dryer, then it’s time to fit weatherstripping. 

• If you can see a crack or gap in the frame, then it’s definitely time to think about weatherstripping.

 

Choosing the right window weatherstripping

There are a number of different types of weatherstripping:

• Adhesive-backed foam. Adhesive-backed foam is inexpensive and easy to fit. It comes in rolls that you simply cut to size and apply. You can only use this stripping on friction-free parts of a window, such as the lower window sash, however. In other areas, this type of stripping will peel off when the window is opened or closed.

• Vinyl stripping. V-shaped vinyl stripping is also sold in rolls and is also easy to fit. You can use this on the side or the top of window frames. One side of the V-shape sticks to the surface of the window frame, while the other side folds in as the window is closed, creating a shield that blocks a draft. A combination of adhesive-backed foam and vinyl stripping is a good solution for sash windows.

• Spring metal stripping. This type of weatherstripping works in the same way as vinyl stripping, but looks more attractive. The metal strips are nailed into place, rather than via adhesive, so this is trickier to fit than vinyl stripping. You can buy spring metal stripping in a variety of different finishes.

• Felt. Felt is now considered to be quite an old-fashioned product, but it is versatile and can be used on a variety of surfaces. Felt has to be nailed, glued or stapled. While not difficult to install, it tends to be more visible than other options and not as effective at stopping airflow.

 

The best time to fit weatherstripping

Most weatherstripping products need to be installed when it is warm and dry so that any adhesive required can dry thoroughly and robustly. Summer—as long as it’s not a rainy day—is the ideal time to fit weatherstripping so the house is ready for fall and winter. However, if you're late to the game, choose a warmer, sunny fall day.

 

Ease of DIY weatherstripping

The ease of installation varies according to the type of weatherstripping that you use.

• Always follow the manufacturer’s guidelines. 

• As a basic principle, always apply weatherstripping to clean, dry surfaces. 

• Ensure that you measure the area carefully before cutting anything to size. 

• Some self-adhesive products may not be effective on certain surfaces, such as metal, so you may need to invest in some extra-strong adhesive too.

Tip: Make sure you clean all surfaces before installing weatherstripping. In the event that you are replacing weatherstripping, remove any existing product first, including traces of adhesive. This will ensure that you have the most effective insulation possible.

Make sure that you also weatherstrip your doors for maximum insulation. Find out more about this in “Door weatherstripping 101.”