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How to Insulate Doors and Seal Windows for Winter

As the winter days approach once again, we all begin to think about the chilly weather that will no doubt arrive in Washington. The mid-40 to 50 degrees Fahrenheit are a stark contrast to the warmer climates of the summer months and catch us off guard. 

One of the best ways to keep your home warm and cozy this winter is by winter-proofing doors and windows throughout the house. This is made possible by sealing doors and windows for the winter. This guide is an easy guide for how to seal doors and windows in preparation for the cold days ahead this winter season.

Steps to Sealing Doors and Windows for Winter

Insulation has been a method that has been practiced throughout history in various ways. While this process is carried out using different methods, there is still a proven method and process that is most effective for sealing doors and windows. If you follow our steps below, you will be able to save yourself money on energy while enjoying a comfortable atmosphere during the frigid temperatures. 

Assessing Your Home’s Winter Insulation Needs

The first step to effective winter insulation is assessing where it is needed the most. Each home’s needs are different and can vary from year to year. Here’s how to get a good picture of your home’s insulation needs this winter: 

Identify Areas with Drafts and Heat Loss

Walk around your home and feel for drafts around windows and doors. Pay special attention to areas where there is a significant temperature difference. 

Choose Appropriate Insulation Materials and Tools

As you conclude your assessment, take the time to evaluate the type of insulation and sealing materials you will need. We will go over the types of materials available for sealing doors and windows as we provide instructions for doing so. 

Calculate the Budget for the Project

Determine your budget for the insulation and sealing project. Keep in mind the benefits of comfort and energy savings you will reap as you weigh the costs of your project. 

How To Seal Windows for Winter

Sealing windows is especially important, but it will also keep out the cold and moisture. Here’s what you do to seal your windows: 


Weatherstripping is a very popular material used to seal gaps and prevent air, moisture, and drafts from entering through gaps around doors and windows. You can choose from the following: 

  • Adhesive-backed foam tape
  • V-strip
  • Felt strip 

Each of these strip materials come in different brands and thickness. We recommend following the manufacturer’s instructions included with the package of your chosen material. 

Installing Window Film

Window films are known as window tints that are self-adhesive and are applied to the surface of glass windows. Here are some of the most common types of window film: 

  • Solar control film
  • Privacy window film
  • Decorative window film
  • Security window film 
  • UV-blocking film
  • Energy-efficient window film

Before applying window film, make sure that the window is clean. Take precise measurements of the window to cut the film to fit appropriately. If the film isn’t self-adhesive, apply the adhesive solution yourself. After applying the film to the window, you must trim and smooth it out to remove air bubbles. 

Window Coverings 

In addition to the typical insulation described above, consider adding window coverings with thermal properties. Typical window coverings usually include curtains, blinds, or shades. When colder than usual, you’ll need to keep them closed to prevent heat loss out of the house. 

Insulating Doors for Winter

If there are any gaps around your doors, you will feel inconsistent or cold temperatures inside the house. Below are the steps for preventing this by insulating doors for the winter. 

Weatherstripping Doors

Like with windows, there are a handful of materials for sealing doors that suit different insulation needs. Here is a list of the most common ones: 

  • Adhesive-backed foam tape
  • Tension seal
  • Feal weatherstripping
  • Door sweeps
  • Gaskets
  • Metal strips 

Take the time to carefully review the instructions for applying the type of weatherstripping that is most needed for the doors. 

Replacing or Upgrading Doors

In addition to adding weatherstripping for sealing doors and windows for winter, we also recommend assessing the overall condition of your doors. Here are some signs that it may be time for a new door: 

  • Excessive drafts and air leaks, no matter what you do to prevent them. 
  • Visible damage like cracks, dents, and warping. 
  • Difficulty opening or closing the door. 
  • Rattling or loose hardware
  • Faded or peeling finish 
  • High energy bills
  • Insects and pests making their way through the cracks
  • The door is several decades old
  • External noise coming through the door

Is Your AC Ready for the Winter Months?

Winterizing your home by insulating and sealing windows and doors is a practical and cost-effective way to keep the house warm and comfortable throughout the cold months. 

This process can be made even more effective when the pros at CM Heating & Air help prep your AC Unit for the winter months ahead. 

Contact CM Heating & Air today for a free consultation and how this service will benefit your home.

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