How to Insulate Windows with Plastic Film

Plastic shrink film window insulation is one of the most effective and affordable ways to reduce heat loss through windows in winter. A single kit can insulate 9 windows for under $30. Here's exactly how to install it.

How Does Plastic Film Insulation Work?

The film creates an insulating air gap between itself and the glass — similar to how double-pane windows work. This air gap dramatically reduces heat conduction through the window. The film also eliminates drafts by sealing the entire window opening.

What You'll Need

• Window insulation film kit (includes film and double-sided tape)
• Hair dryer
• Scissors
• Clean, dry window frame

• Frost King Indoor Shrink Window Kit 42"x62" 9-Pack — includes clear shrink film and double-sided tape; covers 9 windows up to 42"x62"; shrinks crystal clear with a hair dryer

Step 1: Clean the Window Frame

Wipe the window frame where the tape will go with rubbing alcohol. Let dry completely. The tape won't adhere to a dusty or oily surface. This is the most important prep step.

Step 2: Apply the Double-Sided Tape

Apply the included double-sided tape around the entire window frame perimeter, about 1" from the glass. Press firmly. Leave the backing paper on for now.

Step 3: Cut the Film to Size

Cut the film about 2" larger than the taped area on all sides. This gives you enough to grip and trim after installation.

Step 4: Apply the Film

Peel the backing from the tape. Starting at the top, press the film onto the tape. Work across the top first, then down the sides, then the bottom. Keep the film as smooth as possible — wrinkles will shrink out in the next step.

Step 5: Shrink with a Hair Dryer

Set the hair dryer to medium heat. Hold it 2–3" from the film and move it slowly across the surface. The film will shrink tight and become crystal clear. Work from the center outward. Don't hold the dryer in one spot — it can melt the film.

Step 6: Trim the Excess

Use scissors to trim the excess film close to the tape edge. The result should be a taut, nearly invisible film across the window.

How Effective Is It?

Plastic film insulation reduces heat loss through the window by 35–45%. On single-pane windows, it effectively converts them to double-pane performance. It also eliminates drafts completely and reduces noise transmission.

Removing in Spring

Peel the film off starting at a corner. The double-sided tape usually comes off cleanly. Any residue can be removed with rubbing alcohol. The window frame is undamaged and ready for summer.

Tips for Best Results

• Install on a dry day — humidity prevents tape adhesion
• Don't stretch the film when applying — let the heat shrink it
• If a bubble won't shrink out, it's usually a small wrinkle — apply more heat
• Install before the first cold snap for maximum benefit