Best Window Insulation Film 2026: Kits That Stop Drafts

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It’s a January evening and you’re on the couch with a blanket, a mug of tea and the TV on, but the curtain by the old window keeps moving on its own. Put your hand near the glass and you can feel the cold pouring off it. The heat is running, the thermostat says 68, and that corner of the room still feels like 60. A sheet of clear plastic, some tape and a hair dryer can fix most of that feeling in an afternoon.

The best window insulation film for most homes is a shrink-film kit like the Duck Indoor 10-Window Kit or the 3M Indoor Window Insulator Kit: clear plastic you tape to the window frame and tighten with a hair dryer. It stops drafts and cold-glass chill for one winter, then peels off in spring. For sliding doors, use a patio-door kit; for gaps around the sash, add foam weatherstripping.

Below: six products for drafty windows and doors, what each one really does, how to put the film up without wrinkles or peeled paint, and an honest look at how much it saves. We researched and compared them from maker and retailer specs and ENERGY STAR and DOE-funded guidance; we did not test them.

Prices change often. We couldn’t confirm current prices for these kits in October 2026, so we haven’t listed them; ENERGY STAR puts the whole project at under $100. Check the current price before you buy.

Our top picks

Window insulation film kits compared

Product	What it covers	Type	Stays up	Best for
Duck 10-Window Kit	Ten 3 x 5 ft windows (62 x 420 in film)	Shrink film + tape	One heating season	Whole-house drafty windows
3M 5-Window Kit	Five 3 x 5 ft windows	Shrink film + tape	One heating season	A few rooms, first-timers
Duck MAX Strength	Rolled film, cut to size	Heavier shrink film + tape	One heating season	Busy rooms, pets, kids
3M Patio Door Kit	One sliding patio door	Shrink film + tape	One heating season	Doors you don’t use in winter
Frost King R338H	10 ft of 3/8 x 3/16 in foam	Weatherstripping	Until it wears out	Small gaps on windows you open
Frost King V25WA	EPDM D-section strip	Weatherstripping	Until it wears out	Wider gaps

Shrink film or permanent window film?

“Window insulation film” means two different products, and it’s easy to buy the wrong one.

Shrink film kits (everything in our picks except the weatherstripping) are thin, clear plastic sheets you stick to the window frame with double-sided tape, a few inches away from the glass. A hair dryer shrinks the plastic tight. The film blocks drafts that sneak around the sash and traps a layer of still air in front of the glass, the same idea as an interior storm window. ENERGY STAR says these covers “are inexpensive, reduce drafts, help the house feel warmer during winter months,” and cut condensation on the window. They come down in spring.

Applied (permanent) window film sticks directly to the glass, like a car tint. Most of it is solar-control film: it cuts summer heat and glare and blocks 95–99.9% of UV light, according to the DOE-supported Efficient Window Coverings site. Some low-e films also reduce winter heat loss a little, but the same source says applied film generally doesn’t add much insulation, recommends storm windows if insulation is the goal, and says removal takes special procedures, best done by professionals. Dark films on older glass can also raise the risk of heat-stress cracks, and many window makers’ warranties exclude aftermarket film, so read your window warranty before you buy any. If your problem is a hot west window in summer, applied film is worth a look; if it’s a cold, drafty window in winter, shrink film is the cheaper, reversible fix.

The best window insulation film kits

1. Duck Indoor 10-Window Shrink Film Insulator Kit: best value

If more than a couple of windows are drafty, this is the box to buy. Duck’s kit (item 286216) has one roll of film measuring 62 by 420 inches and 168 feet of double-sided tape, enough for ten windows of about 3 by 5 feet. You cut the film to each window with a few inches of overlap, run the tape around the trim, press the film on and shrink it with a hair dryer.

• Good: the most coverage per box in our picks; one long roll fits odd window sizes; crystal-clear film once it’s shrunk.
• Watch out: you cut every piece yourself, so measure carefully; like all shrink film, it’s a one-season product and you can’t open the window while it’s up.
• Best for: older homes with lots of single-pane or leaky windows.

Check the Duck 10-Window Kit price on Amazon

2. 3M Indoor Window Insulator Kit (2141W-6): best overall

3M’s kit is the classic: film and double-sided tape for five windows up to 3 by 5 feet, installed with scissors and a hair dryer. Retailers quote 3M saying it stops cold drafts and helps prevent frosty windows, and that it lasts the season. ENERGY STAR’s how-to says the tape “removes easily without damaging the finish,” but test a hidden spot first on old or freshly painted wood.

• Good: simple, widely sold, five precut window lengths; good tape adhesion on clean, dry trim.
• Watch out: sized for 3 x 5 ft windows, so big picture windows need a bigger kit; retailer listings repeat a “90% better R-value” claim for single-pane windows that we couldn’t find an independent test for.
• Best for: first-timers doing a few rooms.

Check the 3M Indoor Window Insulator Kit price on Amazon

3. Duck MAX Strength Window Insulation Kit: best heavy-duty film

Regular shrink film is thin, and a cat, a curious toddler or a dog that loves the window can poke through it by February. Duck’s MAX line uses a heavier-duty film that Duck says creates an airtight seal to block drafts; Duck lists its MAX rolled kits in a 62 by 126 inch size. It goes up the same way: tape, film, hair dryer. Check the box for how many windows your size covers, because the MAX kits come in fewer, smaller rolls than the 10-window kit.

• Good: tougher film for windows that get bumped; same simple install.
• Watch out: fewer windows per box than the standard kit; still a one-season product.
• Best for: kids’ rooms, pet windows and busy living rooms.

Check the Duck MAX Strength kit price on Amazon

4. 3M Indoor Patio Door Insulator Kit (2144W-6): best for patio doors

A sliding glass door is the biggest single piece of glass in many homes, and the track and weatherstripping on older sliders leak a lot of cold air. 3M’s patio-door kit is the same tape-and-shrink system in a size made for a slider. The catch is obvious: once it’s up, you can’t use the door until spring. It makes sense for a slider you never open in winter, or one that leads to a deck under snow.

• Good: one piece of film for a big door; turns a cold wall of glass into a much calmer one.
• Watch out: blocks the door for the season; never cover a door or window that’s a fire escape route.
• Best for: sliders you won’t use until spring.

Check the 3M Patio Door Kit price on Amazon

5. Frost King R338H Rubber Foam Weatherseal: best for sash gaps

Film isn’t the answer for a window you need to open, like a kitchen or bathroom window. Self-stick foam weatherstripping is. Frost King’s R338H is a 10-foot roll of sponge rubber foam, 3/8 inch wide and 3/16 inch thick, that you press onto the sash or stop where light or air comes through.

• Good: cheap, stays up year-round, and the window still opens.
• Watch out: 10 feet doesn’t go far (a 3 x 5 ft window has 16 ft of edge); foam compresses and wears, so check it each fall.
• Best for: small gaps on windows you open often.

Check the Frost King R338H price on Amazon

6. Frost King V25WA EPDM D-Section Weatherseal: best for bigger gaps

When foam tape is too thin to close the gap, a rubber profile works better. The V25WA is Frost King’s self-stick EPDM rubber strip with a D-shaped section that squashes to fill wider, uneven gaps around sashes and doors. EPDM is a durable synthetic rubber that holds its shape longer than open foam.

• Good: handles wider gaps than foam; durable rubber.
• Watch out: too thick for tight gaps, where it can stop a window from closing; check the strip size on the package against your gap.
• Best for: older windows and doors with uneven gaps.

Check the Frost King V25WA price on Amazon

How to put up window insulation film (without wrinkles)

ENERGY STAR rates this an easy one-day project for under $100. You need scissors or a utility knife, a tape measure, rubbing alcohol and cotton balls or a rag, a hair dryer and, for high windows, a step ladder.

1. Pick a dry, mild day. Tape sticks best to clean, dry trim at room temperature, so do it before the deep cold if you can.
2. Clean the trim. Wipe the frame where the tape goes with rubbing alcohol and let it dry. Dust and kitchen grease are why tape lets go in January.
3. Tape the frame. Run the double-sided tape around the face of the trim (not the glass), pressing it down firmly. Leave the backing on until the film is ready.
4. Cut the film with extra. ENERGY STAR says to leave a few inches on each side. Peel the tape backing and press the film on from the top, then the sides, then the bottom, keeping it loosely smooth.
5. Shrink it. Hold the hair dryer a few inches away on high and keep it moving, starting at the corners and working in. Wrinkles pull out as the film tightens. Don’t touch the dryer to the film or hold it in one spot, or it can melt a hole.
6. In spring, pull the film off and peel the tape slowly at a low angle. Warm stubborn tape with the hair dryer first.

One safety rule: keep at least one window in every bedroom openable (unfilmed) as an emergency exit, and never film over a window that’s part of a fire escape plan. Film also shouldn’t touch hot surfaces: keep it away from space heaters and baseboard heaters right under the window.

How much does window insulation film save?

Honestly: some, mostly in comfort, and how much depends on your windows. The U.S. Department of Energy says heat gain and loss through windows are responsible for 25–30% of home heating and cooling energy use, so windows matter. But ENERGY STAR gives “applying plastic over windows” two stars out of five for energy savings, because leaks around windows “may have less impact on energy use than those in the attic and basement.”

For a sense of scale: the DOE-supported Efficient Windows Collaborative says a regular storm window cuts conduction and radiation heat loss from a typical single-pane wood window by roughly one-third. Shrink film works on a similar principle, but it’s a thin plastic sheet held up with tape, not a sealed rigid panel, and we found no independent test of the retail kits. So treat film as a cheap way to stop drafts and cold spots, with a smaller, uncertain effect on your bill. The bigger the leak and the older the window (single-pane, loose sash), the more you’ll notice.

If your windows are already double-pane and don’t leak, film won’t change much; your money goes further on attic air sealing and insulation (see our DIY attic insulation guide). There’s no federal tax credit for windows, doors or insulation in 2026: the 25C credit ended for work completed after December 31, 2025. Some states and utilities still run weatherization and rebate programs; check DSIRE, your utility and your state energy office.

How to choose window insulation film

• Count and measure your windows first. Add a few inches on each side of the trim, then buy a kit that covers your total. Rolls (like Duck’s 10-window kit) handle odd sizes better than precut sheets.
• Film the windows you won’t open; weatherstrip the ones you will. A mix of both usually works best.
• Choose heavier film where it will get bumped: kids’ rooms, pet windows, behind furniture you move.
• Check your trim. On fragile old paint or unfinished wood, test the tape in a hidden spot. Some kits use magnetic or reusable frames for this reason.
• For a reusable, longer-term fix, look at interior storm panels: the Efficient Window Coverings site says a well-fitted panel brings a single-pane window close to a double-pane one, at around $60 for a 30 x 60 inch window.
• Summer heat is a different problem. For hot, sunny windows, look at applied solar-control film, shades or awnings instead of shrink film.

Keep exploring

Windows are one piece of a warmer, cheaper winter. Our guide to how to lower your electric bill ranks the biggest wins, and lowering your electric bill in winter covers heating habits. The attic usually beats the windows for savings, so see the best DIY attic insulation, and if you heat one room with a portable heater, read the best space heater for a low electric bill. For how heat moves through glass and walls, see thermal energy and radiant energy, or browse all our energy saving tips.

Window insulation film questions

Does window insulation film really work?

For drafts and cold spots, yes. ENERGY STAR says shrink film covers reduce drafts, make a room feel warmer and cut condensation. The energy savings are modest: ENERGY STAR rates the project two out of five stars for savings, behind attic and basement air sealing. It helps most on old single-pane or leaky windows.

Does the film go on the glass or the frame?

Shrink film goes on the frame (the trim around the window), using the double-sided tape in the kit, so a layer of still air is trapped between the film and the glass. Permanent window film is a different product that sticks directly to the glass, mainly for sun and glare control.

Will the tape pull paint off my window trim?

Usually not on sound paint: ENERGY STAR’s how-to says the tape comes off without damaging the finish. Old, chalky or freshly painted trim is the risk. Test a small piece in a hidden corner, let paint cure fully before taping, and in spring peel the tape slowly at a low angle, warming it with a hair dryer.

Can I use window insulation film on double-pane windows?

Shrink film on the frame is fine on any window, though the benefit is smaller on tight double-pane windows. Applied film stuck to the glass is different: dark films can add heat stress, and many window makers’ warranties exclude aftermarket film. Check your window warranty before applying anything directly to the glass.

How long does shrink film last?

One heating season. You put it up in fall and take it down in spring; the film and tape aren’t reusable. If you want something that comes back every year, interior storm panels or magnetic window inserts cost more up front but are reusable.

Is there a tax credit for window insulation in 2026?

No federal one. The 25C energy efficiency credit, which covered windows, doors and insulation, ended for work completed after December 31, 2025, and film kits never qualified. Some states and utilities offer weatherization help or rebates, especially for income-qualified homes; check DSIRE and your utility.