Fixing Drafty Windows

Windows are a common area for people to notice heat loss in their homes, but they may not be the true cause of the drafts. Insufficient air sealing and insulation can make your windows seem leaky, even if they aren’t. Weatherizing your home with air sealing and insulation can make your home more comfortable while lowering your energy bills. If you're still noticing problems after weatherizing, reconditioning or replacing your windows is an option.

Where’s that cold air coming from?

When hot air rises, it can escape out of leaks in a home’s attic. Then fresh, cold air enters the home to replace the escaped air, coming in through openings around the foundation, doors, and windows. Because of their size and placement, these leaks can be difficult to see, but occupants can usually feel their impact when they create uncomfortable drafts or temperature differences.

To help reduce or eliminate those drafts, you can have your attic insulated and air sealed. This reduces the number of leaks in your home, so heated or cooled air will stay in your living space where it belongs. With less heated and cooled air escaping, your heating or cooling system will be able to more easily and efficiently maintain its set temperature.  

In most homes, insulating and air sealing is a cost-effective way to make your home more comfortable and reduce drafts. If you insulate and air seal and still feel drafts around your windows, it may be time to recondition or replace them.

What kind of windows do I have now?

If you're not sure what kind of windows you have, start by checking for a label in the corner that identifies the window type. If you don't see a label, you can still check them yourself.

Storm windows are a second set of windows installed with the existing windows. Usually, these are outside the original window, but sometimes they're inside. Your storm windows will have their own frame and tracks.

Double-pane windows can be identified by looking closely at the window itself. If you look at the edges of the window, where the window frame is, you will see two panes of glass with a space between them. You may also be able to use a light to check for multiple reflections in the glass. Double-pane windows became more common starting in the 1970s, so you could also make an educated guess based on the age of your home or its last window replacement.

How many panes of glass should each window have?

Before you set out to fix your windows, a good first step is to make sure you have enough panes of unbroken glass in each window, including the ones in your basement or utility room. We recommend having at least two panes of glass on every window in your home. The space between the panes of glass acts as insulation, which regulates temperature. If you already have double-pane windows, this is done. If you have single-pane windows, adding a storm window to each will help you create a double-pane effect. Triple-pane windows are a highly efficient option that will make your home more comfortable and resilient.

Can I fix my windows myself?

If your windows are in relatively good shape, you may be able to do some do-it-yourself activities to improve the comfort and efficiency of your home.

• Install window film to reduce the amount of heat that enters through windows
• Apply reusable rope caulk to the movable sections of the windows to seal gaps
• Caulk around the trim where there are gaps that could fit a credit card or fingernail
• Remove the trim in areas with larger gaps, add closed-cell spray foam to the cavity to seal gaps, then re-install the trim
• Hang and use insulated curtains to help prevent drafts

If you’re not comfortable doing these updates yourself or your windows need more work, you can call a professional for reconditioning.

How much will it cost to recondition my windows?

Before you replace all your windows, you may want to consider reconditioning them as a cost-effective way to improve their efficiency and extend their lifespans. Reconditioning can cost $150–$350 per window, depending on the window’s size and type.

During a reconditioning project, your contractor or window professional will assess the current state to decide what your windows need. They may insulate the space between the window frame and the house, install new window tracks or jamb liners, weather strip, replace loose putty or re-caulk, replace broken glass, and more.

What if I want to replace my windows?

If you’ve weatherized and tried alternative solutions but still feel uncomfortable, it may be time to consider replacing your windows. If this is your plan, installing Energy Star-certified triple-pane (sometimes called high-performance) windows will make your home more efficient, resilient, and comfortable. Depending on the windows, they may also increase your property value. Triple-pane windows cost about $350–$2,500 per window. For more information on triple-pane windows, visit the Wise Window Hub for industry-leading information. 

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