How to Install Window Insulation Film

Quick answer: to install window insulation film, clean and dry the window frame, stick the tape around the frame, then press the clear film onto the tape so it covers the glass and sits smooth and even. Trim any excess film, and seal draughty gaps around the frame with weatherstripping. The film adds a clear layer over the window for the colder months without blocking the view.

What is window insulation film?

Window insulation film is a thin, clear plastic sheet that is fixed to the window frame with tape, so it sits over the glass. It is a simple, no-drill winter fix for single windows and older frames, and it can be removed when the weather warms up.

TidyMend sells a winter window insulation film (70 × 180 cm): a clear film of about 27.6 × 70.9 in with a tape strip in the packaged set. See all window insulation film or the full Draft & Weather Sealing range.

What you need

Window insulation film large enough to cover the frame, with tape
A tape measure
Sharp scissors or a craft knife
A cleaner suitable for your frame, and a dry cloth
Optional: weatherstripping for gaps around opening windows

Step-by-step: how to install window insulation film

Measure the window. Measure the width and height of the frame you will stick the tape to. Check that the film is big enough to cover it with a little spare at each edge. Our film is 70 cm high × 180 cm wide, so compare that with your window before you start.
Clean the frame. Wipe the frame where the tape will go to remove dust and grease, then let it dry completely. Tape sticks best to a clean, dry surface.
Apply the tape. Stick the tape around the frame in one continuous border, pressing it down firmly along its length. Do not remove the top backing until you are ready to fit the film.
Cut the film to size. Cut the film so it overlaps the tape on every side.
Fix the top edge first. Peel the backing from the top strip of tape and press the top edge of the film onto it, keeping the film level.
Work down the sides and bottom. Peel the rest of the backing a little at a time and press the film onto the tape, smoothing it outwards so it sits evenly over the glass.
Trim the excess. Trim any film that hangs past the tape for a neat edge.
Check the edges. Run your finger along the tape to make sure the film is stuck all the way round, with no open gaps.

Some window film kits are designed to be tightened with a hair dryer after fitting. Only do this if the instructions that come with your film say so.

Seal the gaps around the window too

Film covers the glass, but cold air also gets in through gaps around opening sashes and frames. For a fuller winter fix, use it together with draught-proofing:

Gaps around opening windows and doors: foam weatherstripping such as the wedge-profile foam window and door seal strip or EVA foam weatherstripping tape.
Sliding windows: a self-adhesive foam seal for sliding windows.

For step-by-step help with strips, see how to install weather stripping on a door (and windows). For the gap under a door, see how to stop drafts under a door.

Tips for a neat result

Fit the film on a dry day, when the frame is not damp with condensation.
Press the tape down firmly before you add the film; most loose edges start with tape that was not fully stuck.
Test the tape on a small, hidden part of the frame first if you are worried about paint or a delicate finish.
Remember that a window covered with film cannot be opened until the film is removed.

More options in the shop: the Duck MAX Strength window insulation kit, 5 windows, the Frost King V76H patio door shrink kit (ships to the United States only) and the Duck window insulation kit, 10 windows (ships to the United States only).

Frequently asked questions

What does window insulation film do?

It adds a clear layer over the window for the colder months. The film is fixed to the frame with tape so it sits over the glass, and you can still see through it.

Does window insulation film block the view?

No. The film is clear, so it adds a layer over the window without changing the view.

What size is TidyMend’s window insulation film?

It comes in one size: 70 cm height × 180 cm width (about 27.6 × 70.9 in), with a tape strip in the packaged set.

Can I still open the window after fitting the film?

Not while the film is in place, because it is stuck across the frame. Choose windows you do not need to open during the colder months.

Should I use film or weatherstripping?

They do different jobs. Film covers the glass; weatherstripping closes gaps around frames, sashes and doors. Many homes use both.

Looking for privacy rather than insulation? The static cling privacy window film is a frosted, no-glue film for bathroom windows, glass doors and side panels that clings to clean glass with water and lets light through. See more window privacy film.

How to Install Window Insulation Film (Winter Window Insulation Guide)