Does Window Insulation Film Work? Here’s What You Need to Know

Who hasn’t placed their hand on a glass window to gauge the temperatures outside? It comes as no surprise, then, that glass doesn’t exactly serve as insulation in your home. So, if your stunning but drafty windows take up more than their fair share of wall space, window insulation films might have crossed your mind. But does window insulation film work? Yes, but you have to install it correctly. Here’s what you need to know before you buy.

How Window Insulation Film Works

Window film works by preventing unwanted air from entering as easily through the glass, which may otherwise have no insulation whatsoever. Window insulation film weatherizes your home by blocking cold air from entering during the winter and stopping hot air from seeping into the windows in the summer. 

Much like its name suggests, an insulation film is a thin film made of polyester that you can adhere to the interior side of your windows with adhesive tape. You simply clean your windows, cut the film to size, and apply it to your windows. But does window insulation film work, really? Well, both window pros and repair specialists agree that window insulation film is an effective and worthwhile addition to your windows. 

Cost to Install Window Insulation Film

Most window insulation films cost between $5 to $20 per square foot. Keep in mind that the features and quality of the films you choose will affect the cost. For example, the National Fenestration Rating Council (NFRC) verifies glare-resistant film for energy efficiency, giving it an NFRC certification rating. Keep in mind that glare-resistant film with this NFRC rating will cost more than one that lacks these accreditations and features.

The Pros and Cons of Installing Window Insulation Film

Since windows play a major part in regulating the temperature inside your home, it’s no wonder that it can feel a bit stressful to decide on treating your windows. If you’re on the fence about whether to install window insulation film or replace your windows, here are a few pros and cons to help you decide if window insulation film is right for you.

Pros

• Films are more budget-friendly at just $5 to $20 for enough to treat multiple windows. This is much less than the cost of replacing windows entirely, which ranges from $200 to $1,800 per window.

• Window insulation film can mean as much as a 30% to 40% decrease in your utility bills.

• Window films are an easy way to make your windows more energy efficient. 

• If you purchase solar window films, not only will the films insulate your home, but they’ll also block harmful UV lights from entering and warping the furniture inside.

• Films can help prevent shattered glass from spilling into your home.

• Depending on your state and local programs, you might receive rebates for using window films, especially solar films.

Cons

• Window films are best used on single-pane windows, as double-pane glass can fog due to the warmer and more insulated inner panel, despite limiting heat loss.

• While they can help insulate your home, window films won’t sufficiently protect you from hurricanes or other natural disasters.

• Certain window manufacturers may consider window films as a void to their window warranties.

• Like installing a screen on your phone, poorly installed window films can leave unsightly bubbles that are difficult to remove.

If you’re still unsure, or if you want to invest in higher quality, more efficient window films, a home energy auditor can help you determine what you need to do to enhance the insulation of your windows.

When to Hire a Professional Window Insulation Installer

Not everyone likes to install film. If installing protective films on your phone screens is challenging for you—or you don’t want the hassle of fidgeting with unruly plastic sheets—then you might want to hire a local window contractor to do the job. 

Trained professionals can quickly and easily install window film insulation and ensure it properly fits and covers the entirety of your windows. This will ultimately help you get the maximum insulation out of your films.