Window insulation (your first step to keeping out the cold)

Let’s get cozy and talk about window thermal insulation.

Key tips to remember

  • Fewer leaks mean a more efficient, warmer home
  • Keep the chimney closed when not in use
  • Seal cracks around windows
  • Install door sweeps
  • Use ceiling fans

Feeling a draft of cold air that shouldn’t be there? Now is a great time to make sure your home is effectively sealed before the extreme cold of winter settles in. Knowing how to insulate windows for winter and how to cover windows to keep the cold out is an important part of making your home more energy-efficient and taking better care of your furnace or HVAC system, not to mention a great way to lower your utility bills. Knowing how to insulate windows will also make those cold winter nights a lot cozier. Sure, you can insulate windows for summer — you’ll reap the benefits of insulating year-round — but in this case, we’re talking about the best window insulation techniques for cold weather, including window insulation film for winter, plastic for windows, and what you can do with a window insulation kit. Read on!

Energy-saving tips, maintenance and repairs

During the winter season, you fight to do two things: Keep out the cold air and keep in the warm heat. The following five economical tips will help make it easier to stay warmer all season long.

Seal cracks around windows

A weather-resistant temporary caulk helps prevent drafts, keeps out bugs, and insulates your home during the winter months. It’s inexpensive and easy to apply, and once spring arrives, you can simply peel the caulk away without causing damage and open your windows again.

Use ceiling fans

Many people only use ceiling fans during the summer to stay cool, but you can use them to your advantage in the winter too. When the heat you blast in your home rises, you can rotate your fan clockwise and circulate hot air back down. This keeps your entire home warmer for longer.

Keep the chimney closed when not in use

You can’t see through it, but your chimney is a window to outside winter weather. When not using your fireplace, be sure to close the damper to keep out the cold and other elements.

Close off unused rooms

By closing doors to unused rooms, you effectively reduce the square footage your heating system must work to keep warm. Not only does this help your home stay warmer in the areas where you’re actually living, but it can also contribute to significant savings on your heating bill.

Install door sweeps

A door sweep is an affordable way to seal doorways during both the winter and the summer. Use a temporary sweep or install a permanent one at frequently used doorways to prevent warm air from escaping underneath. But remember, there’s more to weatherstripping than just door sweeps. Weatherstripping can involve a variety of materials, including metal, wood, plastic, vinyl, foam, felt, sponge and silicone, which create solid air seals around door frames, keeping warm air in and cold air out in the winter, and doing the reverse during hotter months. Making your doors airtight with weatherstripping can involve various parts, such as:

  • Door sweep: Metal frames or flanges often include vinyl, felt, plastic or sponge bristles, which sweep across the bottom of the door on the inside, against the threshold.
  • V-channel: Also known as a V-strip or tension seal, these are typically metal and installed at the door’s top and along the sides, creating a lasting, mostly invisible seal.
  • Felt seal: Inexpensive and often made with synthetic fibers or wool-based materials, these are installed to improve seals around doors and hinges but aren’t very durable.
  • Foam tape: Made of vinyl, rubber or PVC, this type of weatherstripping is inexpensive and easily installed due to its adhesiveness, yet it also isn’t particularly durable.
  • Bulb flange: A vinyl or silicone bulb flange has a low profile, takes up little space and isn’t an eyesore. While it is fairly durable, it doesn’t fill gaps as well as foam tape.


Best window insulation materials

If you have leaky, old windows, these techniques and materials won’t magically elevate them to the higher-quality realm of modern windows, but they can help you get through a lean season or two more comfortably as you save to invest in new windows, maybe for next year. Here’s some helpful information about a few of the best window insulation materials:

  • Window insulation film: Cut to size and attached inside, plastic film for windows creates a thermal barrier to reflect heat in warmer months and retain it in the winter.
  • Weatherstripping: Cheap but effective, a window sealing kit comes with weatherstripping that may require a window to remain shut until it is removed.
  • Caulk: Caulk is inexpensive and easily peeled or scraped away and replaced. Use silicone-based versions to seal metal and glass, and water-based versions around windows.
  • Spray foam: Used to fill larger gaps unsuitable for caulk, expanding spray foam is sold in a low-expansion version that is easier to control around windows.
  • Draft stoppers: Here’s a great way to fill gaps and eliminate drafts coming from underneath doors or windows. They’re affordable and effective, and also aid in soundproofing.
  • Window treatments: If you don’t like the idea of a plastic window cover, or weatherstripping with caulk, foam or anything else we’ve mentioned, you can invest in energy-efficient window treatments — thick curtains or drapes designed specifically to retain heat. Some have white plastic backs and do double duty in the summer, reflecting outside heat away from the home to keep things cooler inside.

Thanks for reading our post on the wide world of window insulation. While you’re here, you may also have some interest in learning more about what it costs to replace a radiator, what to keep in mind when getting ready to prep your home for winter, some of the benefits of smart thermostats, or even more detail on the importance of weatherstripping doors. At Cinch, we’ve put together a crack team of writers who are constantly on the case, assembling and articulating our best advice on a range of home-improvement topics. We’re happy to have you here.

The information in this article is intended to provide guidance on the proper maintenance and care of systems and appliances in the home. Not all of the topics mentioned are covered by our home warranty or maintenance plans. Please review your home warranty contract carefully to understand your coverage.

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