How to Seal Gaps Around Windows and Why It’s Important

When you’ve settled down on the couch for the evening, a mug of tea in one hand and a good book in the other, you’re ready to be warm. You take a sip of tea. You turn a page. But you have an uneasy feeling in the back of your mind. Looking up, you realize what it is.

seal gaps around windows

There’s a draft. It causes the skin on the back of your neck to prickle. You have to get a blanket and cover up, but the blanket keeps sliding off, and you have to keep setting down your tea to fix it. If only you could just turn up the heat – it shouldn’t be so cold in here! But you’re already spending enough on energy bills each month, so you put the blanket on and deal with the frustration, when all you wanted was a cozy evening free of stress.

You have the same problem in the summer, too. You expect to come home and collapse in the sanctuary of your air conditioning – but your home is never as cool as you want it to be. Certain parts of the house remain decidedly sticky all summer long. You’ve tried turning up the AC, but your children’s rooms get so cold they can’t play inside them anymore. You’re never quite cool enough in one part of the house, but chilled in the other.

Consequences of Window Leaks

drafty windows

It’s not black magic that’s making your home this way. It’s not pixies or elves making mischief with your temperatures. You may be suffering from a home invasion. It’s not a rodent. It’s not a bug. It’s not a mold, mildew or fungus. No, your home is likely being invaded by air.

Windows often create the illusion of being weather-proof. After all, the rain doesn’t get in. Snow and hail and bugs and debris are also kept outside by windows. And while windows do an excellent job at these things, most windows let in the invisible side of weather: air.

You may have heard that your home is losing heat each winter through gaps in your windows. In fact, the average home loses up to 30% of heating and cooling energy through air leaks. We’d all rather send our children to college than pay hundreds of accumulated dollars in energy bills. Yet we sit by as precious heating and cooling gets sucked out through the window.

Not only is heated and cooled air getting out of your home, other things are getting in. Air contaminates sneak through these tiny cracks and float their way about your home. Moisture gets in, creating mold and general discomfort.

Last, but not least, your window gaps are not just costing you, they’re costing the environment. The less energy you use, the better off your grandchildren and their grandchildren will be. The little things often do the most long-term good, and you can start creating a better world by creating a leak-proof home.

While a home can have multiple forms of air leaks, the two most common are doors and windows. While the knowledge that your home is costing you money every year can be frustrating, it’s a surprisingly simple problem to solve.

Here are steps and tips you can follow to alleviate air leaks.


One of the easiest ways to check for gaps is incense. Not through a magic spell; the smoke is drawn to the air gaps.

Simply walk through your home with a lighted incense stick, stopping near likely places. (Doors and windows are the best place to start.) If the smoke is drawn towards the window instead of straight up, then you know you have an air leak.


Now knowing where your problems exist, you can make a list of what areas in your home you want to seal. You have a couple of options when it comes to sealing your home, the following being the most common:


An old standby. Caulk is relatively inexpensive and easy to come by, and if you can drag a nozzle in a straight line, you can install it.

The downside of caulk is that it’s messy, covers in mold easily, and only lasts a couple of years before it begins to buckle and crack, recreating your problem.

Bronze Weather Stripping

Though difficult to install and expensive, this solution lasts for decades. If you’re looking to stop the problem once and for all, this may be the option for you.

Self-Stick Plaster Types

Easier to install, these only last a couple of years. Still, they may be the right choice for you at the moment since they’re not as pricey as other options.

Adhesive-Backed EPDM Rubber

This option is a wonderful blend of quality and price; it’s not as steeply priced as bronze weather stripping, but lasts at least ten years.

If you’re looking for a good compromise between cost and longevity, this may be the one for you.

Pulley Seals

In addition to getting a product to block your long window gaps, you should also consider getting a pulley seal, which is specially made to block the air that slips in near window cords.

Once you’ve made your choice on what product will give the best result for you, you can head on over to the hardware store and pick it up. Then start fixing!

Sealing Gaps Around Windows Is Easy and Important

It only takes a brief walk with an incense stick and a day of home improvement to fix your air leak problems. Since every day there’s more energy wasted, the sooner you’re able to take care of your air leaks, the better. Once your windows are properly sealed, you can live in peace knowing your home is protected from drafts. The environment will thank you–and so will your energy bill. It’s a great way to improve your windows.

For homeowners who have windows that are past their prime, replacement is the only true solution to eliminating leaks. In such a case, Feldco is here to help.

With over 400,000 homeowners served in the Midwest, we know a thing or two about window replacement. Get a free quote now to see why we’re named America’s #1 window company.

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