Window Leaks, Best Tests and Repair Tips

If your windows are letting air escape through small leaks, you might find out in a couple of ways. One, a room might feel warmer or colder than the rest of your house. The other notification would be from your wallet: Leaks lead to higher energy bills.

If you suspect a leak, it’s important to confirm as quickly as possible so you can try to repair it. Prolonged leaks will be uncomfortable and expensive, and won’t get any better on their own. Try these methods to find and treat a leaky window.

Sight and touch tests. The first and easiest method is to simply walk outside and check the exteriors near the windows in question. If you see cracks or holes near the windows, you’ve found your leak. You can also feel around the windows both outside and inside for air escaping out or in for clear signs of a window leak.

Light test. If the leaks aren’t that obvious, try a simple light test. During the day, turn off all the lights in the room where you suspect a leak. Then inspect the area around the window. If you can see daylight, you have a small leak. This test is also good to perform periodically as part of smart maintenance whether you think you have a leak or not. But if you see daylight, you have one.

Candle Test. If you’re still not sure, a candle can help you find a leak once and for all. Using a lit candle, trace a path around your window. If you see the flame or smoke pull toward the window, you have a leak. And to be 100 percent sure, have someone stand outside the window with a hair dryer or leaf blower. If they aim toward the window and your candle reacts, air is getting through.

Fixing A Leak

Okay, you’ve found the leak. Now what? It’s time to try to repair it, and the process is pretty straightforward. Here’s what you’ll need and what to do in order to get the project done right.

Window Frame and Grille. To repair this area you’ll need caulk and a putty knife. Always start out by removing old caulk and paint with the knife, cleaning the area with soap and water, and letting it dry. Apply caulk to the area at a 45-degree angle, in a continuous stream if possible. If the caulk leaks out, use the putty knife to reposition it, and reapply caulk as necessary until the leak is covered. Always apply in smooth lines.

Lower Rail and Window Sill. This repair includes weatherstripping. Again, clean the area with soap and water and let it dry. Then open the window, measure and cut the weatherstripping accordingly and apply, making sure you have a good seal when the window is shut.

After these repairs, repeat the leak tests to make sure it’s covered and no longer letting air out.

Still Having Problems? Try Mister Window.

If the above repairs didn’t stop the leak, or the fix ends up being temporary, it might be time to replace your windows. For more than 45 years, Mister Window has been a leader in selling and installing replacement windows, impact windows and hurricane-resistant windows. Serving Hillsborough, Pinellas, Manatee and Sarasota counties, we have the inventory and experience to make sure your windows are look and perform exactly that way you want. The people who work on your project are our employees, and dedicated to our values and commitment to excellent service. That service includes keeping you informed every step of the way, and a thorough walk-through when the job is done to ensure you’re completely satisfied. And we’ll start with a free home consultation, which can be in-person or virtual, get all necessary information, and make sure our plans meet your specifications. Simply contact us here with any questions or to schedule your home inspection.

Mister Window

February 17, 2023

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