Best Draft Stoppers & Window Insulation Kits to Keep Your Home Warm

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That chilly breeze by the window or the cold air sneaking under your front door isn't just uncomfortable. It's money leaking out of your house. ENERGY STAR estimates homeowners can save an average of about 15% on heating and cooling costs by sealing air leaks and adding insulation.

The best part? Most draft fixes cost under $20, need no tools, and take less than an hour. Here are the products worth buying, how to choose, and how to install them so they actually work.

How we chose: We compared product specifications, independent reviews and long-term owner feedback, focusing on how well each product seals, how easy it is to install and remove, and how it looks. Prices change. Check the current price before you buy.

Our top picks at a glance

Product	Type	Best for	Price
3M Indoor Window Insulator Kit	Shrink film	Best overall window kit	$
Frost King Window Insulation Kit (multi-pack)	Shrink film	Best value for many windows	$
Duck MAX Strength Window Kit	Thicker shrink film	Homes with pets/kids	$
Twin draft guard (under-door, slide-on)	Foam door draft stopper	Best for interior & exterior doors (no tools)	$
Adhesive door sweep	Door bottom seal	Gaps under exterior doors	$
Foam or V-strip weatherstripping	Weatherstripping	Gaps around door frames and window sashes	$
Removable rope caulk	Temporary caulk	Sealing window cracks for one season	$
Outlet & switch foam gaskets	Foam gaskets	Drafty outlets on exterior walls	$

$ = typically under $25.

Window insulation kits

Window insulation kits use a clear plastic film that you attach to the inside of the window frame with double-sided tape, then shrink tight with a hair dryer. The film traps a layer of still air between it and the glass, which acts like an extra pane. It's nearly invisible once installed and peels off in spring.

They're especially effective on older single-pane windows, drafty windows and rooms that always feel cold.

1. 3M Indoor Window Insulator Kit: Best overall

3M's kit is the one most reviewers and homeowners reach for first. The film shrinks clear and tight, and the double-sided tape holds well all winter.

✅ Clear, wrinkle-free finish when shrunk properly
✅ Available in packs for multiple windows, plus patio-door sizes
⚠️ The tape can pull paint off some window frames, test a small spot first

2. Frost King Window Insulation Kit: Best value

If you have a lot of windows to cover, Frost King's multi-packs are one of the cheapest ways to do the whole house.

✅ Low cost per window
✅ Works well on standard windows
⚠️ Film is a bit thinner, handle carefully during install

3. Duck MAX Strength Window Kit: Best for pets and kids

Duck's thicker film is more resistant to punctures from curious pets and little fingers.

✅ Thicker, tougher film
✅ Good for high-traffic rooms
⚠️ Slightly more visible than thinner films

How to install a window insulation kit (step by step)

Clean the window frame with rubbing alcohol and let it dry completely. Tape won't stick to dust or grease.
Apply the double-sided tape around the frame (on the trim, not the glass). Press firmly.
Wait 15 to 20 minutes for the tape to set, skipping this is the #1 cause of loose film.
Cut the film about an inch larger than the tape on each side.
Press the film onto the tape, starting at the top, then sides, then bottom. Pull gently so it's fairly smooth.
Shrink it with a hair dryer on high, holding it a few inches away and moving constantly. Wrinkles disappear as the film tightens.
Trim the excess film with a utility knife.

Tip: Do it on a mild, dry day if you can, tape sticks best at room temperature.

Door draft stoppers

The gap under a door is one of the biggest draft sources in many homes. Here's how to choose:

Option	Best for	Install
Twin draft guard (two foam tubes that slide under the door)	Interior doors, exterior doors with small gaps	No tools; moves with the door
Adhesive door sweep	Exterior doors	Peel and stick
Screw-on door sweep	Exterior doors, larger gaps	Screwdriver; most durable
Weighted "draft snake"	Rarely-used doors, renters	Just lay it down
Door threshold seal	Worn thresholds	Varies

4. Twin draft guard: Best no-tool door stopper

A twin draft guard has two foam tubes connected by fabric that slides under the door. One tube on each side. It moves with the door when you open and close it, so you don't have to put it back every time.

✅ No tools or adhesive
✅ Cut to fit most doors
⚠️ Not ideal for doors with very large gaps or thick carpet

5. Adhesive or screw-on door sweep: Best for exterior doors

For exterior doors, a door sweep attached to the bottom of the door gives a more permanent seal. Silicone or rubber sweeps adjust to uneven floors.

Quick test: Close the door on a sheet of paper. If it slides out easily, your door needs a better seal. If you can see daylight around the door, it definitely does.

Weatherstripping

Weatherstripping seals the gaps around doors and the moving parts of windows.

6. Foam tape or V-strip weatherstripping

Self-adhesive foam tape: Cheap and easy; good for irregular gaps. Replace every year or two.
V-strip (tension seal): Plastic or metal strip folded into a "V" that springs open to seal gaps. Very durable and nearly invisible; great for door jambs and the sides of sash windows.
Rubber/silicone door seal kits: Replace the worn seal in the door frame for a like-new fit.

7. Removable rope caulk: Best temporary seal

Rope caulk is a soft, putty-like strip you press into gaps around window frames by hand. It seals cracks for the season and peels off cleanly in spring, perfect for renters or windows you open in summer.

8. Outlet & switch foam gaskets

Outlets and light switches on exterior walls can leak surprising amounts of cold air. Pre-cut foam gaskets fit behind the cover plate. Turn off the power at the breaker, unscrew the cover, add the gasket and replace the cover.

How to find the drafts in your home

Do the smoke test: On a windy day, hold a lit incense stick near window frames, door edges, outlets, baseboards and attic hatches. If the smoke wavers or blows sideways, you've found a leak.
Use your hand: Feel for cold air on a cold, windy day.
Look for light: At night, have someone shine a flashlight around a door frame from outside while you look for light from inside.
Use a thermal camera or thermal leak detector for the most accurate results.

Common draft spots: window frames and sashes, under exterior doors, door frames, attic hatches, outlets on exterior walls, around pipes and wires, fireplace dampers, and dryer vents.

How much can you save?

Results vary by home, but sealing drafts is consistently one of the cheapest, highest-return winter upgrades. ENERGY STAR's estimate of about 15% savings on heating and cooling comes from combining air sealing with added insulation. Even on its own, sealing the worst leaks makes rooms feel noticeably warmer, so you can lower the thermostat, and the U.S. Department of Energy says turning the thermostat back 7 to 10°F for 8 hours a day can save up to 10% a year.

👉 More ways to save: 12 Ways to Lower Your Heating Bill This Winter

Frequently asked questions

Do window insulation kits really work? Yes, especially on older single-pane or drafty windows. The film creates an insulating air pocket and stops drafts around the sash. They're one of the cheapest ways to make a cold room feel warmer.

Will window film damage my paint? The tape can sometimes lift paint, especially on older or poorly-bonded paint. Test a small hidden area first, and remove the tape slowly in spring, pulling at a low angle. A hair dryer can soften stubborn tape.

Can I still open my windows with insulation film? No, the film seals the window shut until you remove it. Leave at least one window in key rooms uncovered for ventilation or emergencies, and never cover a window that's an emergency exit.

What's the best draft stopper for under a door? For interior doors, a twin draft guard is easy and effective. For exterior doors, a door sweep attached to the bottom of the door gives the best long-term seal.

How often should I replace weatherstripping? Foam tape usually lasts a year or two. Higher-quality rubber, silicone or V-strip weatherstripping can last several years. Replace it whenever it's cracked, flattened or peeling.

The bottom line

For most homes, start with the 3M Indoor Window Insulator Kit on your coldest windows, a twin draft guard or door sweep on drafty doors, and weatherstripping around door frames. Together, they cost less than a single month's heating bill, and you'll feel the difference right away.

Getting ready for winter? Use our Complete Winterize Your Home Checklist.