How to Insulate Your Windows for Winter

How to Insulate Your Windows for Winter

One of the best ways to save money on your heating bill is by sealing up cracks in windows. That’s why winterizing them before the cold season starts will help you survive those frigid days and nights without turning up your thermostat.

In the below post, we’ll review best practices on how to insulate your windows for winter. We’ll also evaluate whether insulating your windows is worth the cost.

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5 Ways to Winterize Your Windows

As the temperature outside starts to drop, you may notice that you have a tough time keeping your home warm. Often, this is because of poorly insulated windows.

In fact, heat gain and heat loss through windows are responsible for 25%–30% of residential heating and cooling energy use.

While windows can be a big source of heat loss in your home, there are multiple ways to winterize them. If you’re looking for the most cost-effective ways to winterize your windows without replacing them, consider the following tips.

Air Seal and Caulk

Air leaks are caused by air passing through cracks and gaps around your windows.

These can be as small as a hairline crack in the window frame or something much larger like an open door, but they all have one thing in common: cool drafts that make you shiver on those cold days throughout winter months. If you feel these uncomfortable breezes at any point of time during the year then it’s worth having them checked out to ensure no heat is being lost where it should stay warm.

Inspecting the exterior of your windows for cracks and gaps is a good place to start. Make sure you look over all window frames, as well as caulking that may be deteriorating or rotting wood. These signs can lead to big problems in both functionality and safety. Check if there are any missing pieces from the glass itself (which will not only hinder light coming into your home but also make it easier for intruders).

When it comes to caulking, the best advice is often given in the worst order. First, make sure you clean and dry the area of any debris before replacing your old caulk with new one. Caulk will not stick if there are dust or dirt particles on top that could attract moisture which causes mold growth – another major concern for those looking out for their health as well as preserving property values.

Check out our detailed post to find the best caulk for air sealing windows, doors, and other parts of your home.

Weather Stripping

Weather stripping is a type of sealing material that can be used to seal doors and windows. It comes in three different types: felt, foam, or metal/vinyl strips. The most common weather stripping material is open-cell foam. When trying to decide which one will work best for you think about what your needs are as well as any pros or cons associated with each option based on their thickness (felt), flexibility (foam), and durability (metal).

How to Insulate Windows for Winter - Weather Stripping

In terms of the best foam weather stripping products, we often recommend MAGZO Foam Tape Weatherstrip. This foam weather stripping tape can be used as insulation, shock absorption and sound absorbing materials. It is easy to handle, manageable, and can be cut and conformed to a variety of shapes and sizes, making it a good foam strip for windows, doors, or any place you need to prevent unwanted heat transfer.

Thermal Window Treatments

Another way to help insulate your windows is by adding some insulating window treatments.

To do this, you can use curtains made of insulating material such as wool or silk. If you prefer to keep your windows clear and open, check out insulating blinds that are similar in concept but different in application. They’re also sold with a variety of insulating materials like aluminum composite, which is very lightweight and easy to transport should you need to relocate for various reasons.

Foam Insulation Kits

If you want a permanent solution to insulate your windows, then getting some foam insulation kits may be what you need. The beauty of these products is how well they are designed – from the ease of installation right down to their efficient design.

When installing foam insulation kits make sure you follow the instructions on the box. Even if you are somewhat confident in your abilities to install this insulating foam product, read up on any tips or warnings it may have. The insides they contain are compressed and easy to break free but once released all that force can come at a price.

Foam insulation kits come in varying sizes – typically a 2×4 foot section of starter kit insulates 10 square feet of space. Take note that these insulating kits do not include everything needed for installation; you will also need an adhesive like Super 77.

When setting up your insulating kit, make sure any surfaces you’re working with are clean before getting started.

Window Film

Window films are a clear, insulating barrier that are applied to each side of the window. They help insulate the home by slowing down the rate of heat loss through windows.

Window film insulates and improves a building’s thermal efficiency. The insulating window film shields the room from outdoor weather conditions such as rain or cold winds.

In terms of cost, window films are typically more expensive than insulating materials such as insulating curtains or blinds. With that being said, they can be effective insulators and they don’t block the view from outdoor to inside which insulating curtains or blinds would.

How to Insulate Windows for Winter - Window Film

Our favorite window film is made by 3M. The 3M Indoor 1-Window Insulation Kit is designed for insulating windows located between the inside and outside of your home. This product is quick and easy to install and can help homeowners save on energy bills.

Is Insulating Your Windows Worth It?

Is Insulating Your Windows Worth It

Insulating your windows is relatively cheap. Most blinds and window treatments cost between $75-150 for insulating window treatments. Meanwhile insulating kits cost around $25 per 2×4 ft. insulator – which if you are insulating all of your windows that means spending anywhere from $50 to a few hundred dollars depending on the size and size of your home.

The costs can add up but it is often worth the money because it’s an easy solution (compared to replacing your windows). Plus, because installation is simple, most people choose to insulate their windows regardless of cost. It beats living in a super cold or hot home year after year without insulating them.

In terms of ROI and cost savings from insulating windows, there are a number of variables that impact cost savings. For instance, where you live, how often you use your heating and cooling systems, your utility costs, the type of windows, and the age of your windows all play a role in savings. This makes it relatively challenging to answer if insulating your windows is entirely worth it. Ultimately, the best way to make a decision is to ask yourself if you’re willing to sacrifice comfort. If the answer is no, then insulate your windows.

Should I just replace my windows?

Should I just replace my windows

Air sealing and adding insulation materials is a cost effective way to squeeze some extra life out of your windows. But, at some point, it may be easier to bite the bullet and just replace your windows altogether.

Some signs you should replace windows include:

  • Leaking around the window frames. Air leaks can happen when windows are installed or even if they age. Sometimes insulating your windows with insulating kits isn’t enough to stop sealing issues from popping up.
  • Condensation and ice buildup on your windows during times of cooler weather or heavy rainfall.

Replacing old, drafty windows is a necessity for insulating your home effectively – especially if you live in colder climates. However, this solution isn’t cheap. The average cost of replacing one window is anywhere between $300-$500 depending on where you get them from and what kind of material you want (vinyl, wood, aluminum). Frequently, you can insulate all of the windows in your home for the same price of one replacement window.


In the end, insulating your windows is a cheap way to improve your energy efficiency at home. It’s an easy project that can be done in as little as an hour by anyone with basic DIY skills and little money. Anything from insulating kits to insulating curtains and blinds will help insulate your windows for winter effectively.