Homeowners living in older houses often lose expensive heat straight through loose window frames and door sills. You can draft-proof windows by applying self-adhesive foam or rubber strips to the moving parts of the frame, and using silicone sealant for cracks in the fixed frame. For larger gaps, sliding windows, or exterior doors, brush strips or metal wiper seals offer a more durable solution.
Quick answer
Seal fixed frame cracks with silicone caulk and use weatherstripping for moving parts to stop drafts immediately. Renters should use temporary shrink film to block cold air without damaging paint.
- Best for quick, cheap fixes: Self-adhesive foam tape
- Best for sliding or sash windows: Brush strips
- Best for uneven gaps: Silicone EPDM rubber seals
- Best for winter renters: Window insulation shrink film
- Sealing drafts around windows and doors can save a typical US home about $55 to $60 a year on energy bills.
- Test your current seals using the paper test before buying materials.
- Always try adjusting the hinges on modern uPVC windows before replacing the rubber gaskets.
- A 1/8-inch gap under a standard 36-inch wide door lets in as much cold air as a 2.4-inch hole in the wall.
- How do you find exactly where a window is drafting?
- What is the difference between V-strip, foam tape, and brush weatherstripping?
- What is the best material to draft-proof wooden windows?
- How do you draft-proof sash windows?
- Can you draft-proof UPVC windows or adjust their hinges?
- How to keep drafts out of windows without replacing them?
- Are window insulation shrink films effective for drafty windows?
- How do you draft-proof front and back doors?
- What do owners say?
- Frequently Asked Questions
How do you find exactly where a window is drafting?
You cannot effectively seal a window until you know exactly where the air is leaking. Cold air finds the path of least resistance. Sometimes the leak is between the window sash and the frame. Other times, it happens where the window frame meets the drywall.
Use this four-step DIY draft diagnostic checklist to pinpoint the leaks.
- Visual Check: Look for daylight shining through the edges of closed doors and windows. Inspect old caulking for dry rot, cracking, or peeling.
- The Hand Test: On a cold, windy day, run your damp hand slowly around the edge of the window frame. The moisture on your skin makes it highly sensitive to temperature changes, helping you feel even faint breezes.
- The Paper Test: Open the window, place a standard sheet of printer paper across the seal, and close and lock the window. Pull the paper. If it slides out easily, the seal is broken. If the paper tears or resists pulling, the seal is tight. Repeat this around the entire perimeter.
- The Candle Test: Turn off all ceiling fans and close exterior doors. Light a candle or an incense stick and move it slowly around the window edges. If the flame flickers wildly or the smoke blows horizontally into the room, you have found a draft.
What is the difference between V-strip, foam tape, and brush weatherstripping?
Walking down the hardware store aisle, you will see dozens of draft-proofing coils. They fall into four main categories. Choosing the right one depends on the size of the gap and how the window operates.
| Material | Best Application | Expected Lifespan | Relative Cost |
|---|---|---|---|
| Self-Adhesive Foam Tape | Immediate, temporary relief on casement windows or fixed frames. | 1 to 3 years | $ (Lowest) |
| Silicone EPDM Rubber | Uneven gaps. Compresses from 1/16-inch to 1/4-inch. | 5 to 10 years | $$ |
| V-Strip (Tension Seal) | Sides of double-hung or sliding wooden windows. | 10+ years | $$$ |
| Brush Weatherstripping | Sliding sash windows, door bottoms, and track systems. | 10 to 15 years | $$$ (Highest) |
Self-adhesive foam strips are the cheapest option. They are easy to cut and apply. However, they typically only last one to three years before degrading, losing adhesion, or flattening completely. Foam also absorbs moisture, which can freeze during severe winter storms.
Silicone-based rubber tubular seals (EPDM) perform much better. They are hollow inside, allowing them to compress tightly when the window locks. They easily accommodate gaps ranging from 1/16-inch to 1/4-inch without putting excessive strain on the window latch.
What is the best material to draft-proof wooden windows?
For wooden casement windows (windows that crank outward on hinges), EPDM rubber seals are the best material. Wood expands and contracts with humidity and temperature changes throughout the year. The hollow rubber tube compresses to match these seasonal changes, keeping a tight seal.
Applying the material requires good preparation. First, scrape off any old weatherstripping. Clean the wooden frame using rubbing alcohol or a mild degreaser to remove dirt and oils. If the wood is bare, applying a thin coat of paint or primer and letting it dry completely will give the adhesive a much stronger surface to grip.
Cut the rubber seal to length and press the adhesive side firmly into the frame stop,the part of the frame the window pushes against when closed. Do not stretch the rubber as you apply it. Stretching causes the material to snap back over time, leaving gaps in the corners.
How do you draft-proof sash windows?
Traditional sliding timber sash windows are notorious for rattling in the wind and letting cold air pour in. Draft-proofing these requires a different approach than casement windows. You cannot use foam tape here; the sliding action of the window will quickly shred the foam.
Brush strips are the standard recommendation for sliding sash windows. They feature a rigid backing with dense nylon bristles that glide smoothly against the moving wood. They boast a lifespan of 10 to 15 years.
To seal the vertical sides of a sash window, you usually replace the parting bead,the thin vertical strip of wood separating the top and bottom sashes. Modern replacement parting beads come with a channel already routed into them, holding a brush strip that presses directly against the sliding windows.
Can you draft-proof UPVC windows or adjust their hinges?
Modern uPVC (unplasticized polyvinyl chloride) windows have rubber gaskets built into the frame. When they draft, many homeowners immediately assume the gasket has failed. Often, the real culprit is a misaligned hinge.
From the Shop
We frequently see homeowners stick cheap foam tape directly over the built-in rubber gaskets on uPVC windows. This creates too much pressure. When they force the handle down, the extra bulk completely snaps the internal locking mechanism. Never stick weatherstripping directly onto a uPVC window’s moving seal.
Over time, the heavy glass causes the window sash to sag slightly. This pulls the top corner away from the frame, creating a gap. Use this troubleshooting logic to fix uPVC drafts:
1. Close the window on a piece of paper.
2. If the paper slides out easily near the hinge side → Adjust the hinge tension screws with an Allen key to pull the sash tighter to the frame.
3. If the paper slides out easily on the handle side → Adjust the window locking keeps (the metal cams on the edge). Turn them with an Allen key to increase closing pressure.
4. If the paper slides out easily everywhere and the rubber looks permanently flattened or cracked → Pull out the old gasket and push a new replacement gasket seal into the track.
How to keep drafts out of windows without replacing them?
Full window replacements cost thousands of dollars. If you are a renter, replacing windows is entirely out of your control. Fortunately, you can keep drafts out using non-permanent methods that will not damage the property.
Heavy thermal curtains with a tight weave block drafts effectively. To work properly, the curtain must drop all the way to the floor or rest directly on the window sill, trapping the cold air behind the fabric. Draft excluder cushions (fabric tubes filled with sand or polyester) laid across the bottom sill stop the heaviest cold air from rolling off the glass and onto your floor.
Are window insulation shrink films effective for drafty windows?
Yes. Window insulation shrink films are highly effective, especially for single-pane windows. They create a dead-air space between the cold glass and your warm room. This trapped air acts as a strong insulating barrier.
Kits come with double-sided tape and a large sheet of clear plastic film. You stick the tape around the window trim, press the plastic onto the tape, and use a standard hair dryer to shrink the film. The heat makes the plastic pull tight like a drum, removing wrinkles and making it nearly invisible.
While effective, they have downsides. Once installed, you cannot open the window. Additionally, leaving the double-sided tape on for more than one winter season often leads to peeled paint when you finally remove it.
How do you draft-proof front and back doors?
Exterior doors leak massive amounts of heat. A 1/8-inch gap under a standard 36-inch wide door lets in as much cold air as a 2.4-inch hole punched directly through your living room wall.
To seal a door perimeter, install EPDM rubber weatherstripping inside the door jamb. The door should compress the rubber slightly when latched. For the bottom gap, install a door sweep. Metal sweeps with flexible rubber or brush bottoms screw directly into the lower face of the door, dragging slightly against the threshold to block wind.
Do not forget the small penetrations. Mail slots (letterboxes) and keyholes allow freezing air to pour straight into entryways. Install an internal brush cover over the mail slot to block wind while still allowing mail to pass through.
What do owners say?
Owners like
- Foam tape is incredibly cheap and easy to apply for immediate, temporary relief.
- Shrink film kits make a massive thermal difference on single glazing during winter.
- EPDM rubber seals last much longer than cheap foam ones and don’t absorb water.
- Magnetic secondary glazing is highly praised for being removable in the summer.
Common complaints
- Foam strips often unpeel after a few months, especially if the frame wasn’t perfectly degreased.
- Applying shrink film with a hairdryer can be tedious, and the double-sided tape often damages paint upon removal.
- Applying too thick of a rubber seal makes windows and doors very difficult to close and lock.
- Brush strips on sash windows can sometimes catch and make the window stiff to open.
Summarised from owner reviews and long-term user reports; individual experiences vary.
Frequently Asked Questions
how to draft proof windows
Clean the window frame thoroughly and apply self-adhesive EPDM rubber weatherstripping to the moving parts. For fixed frames with cracks, use a silicone sealant to block the air. Ensure you use the paper test to locate the exact gaps before applying materials.
how to draft proof windows uk
Whether you are fixing windows in the US or looking at methods from the UK, traditional timber sash windows require specific attention. Instead of foam tape, you must replace the parting bead with a modern version that holds a friction-resistant brush strip to allow the wood to slide without tearing the seal.
how to draft proof windows and doors
Combine perimeter weatherstripping with bottom seals. For windows, use rubber or V-strips on the side jambs. For doors, install a metal and rubber sweep at the bottom to block threshold drafts, and seal any mail slots or large keyholes with dedicated brush covers.
how do you draft proof windows
Identify the gaps using the paper or candle test. Clean the area with a degreaser. Cut your chosen seal,foam for temporary fixes, rubber for durability, or brush for sliding tracks,and press it firmly into the frame stop so the closed window compresses it.
how to keep draft out of windows
If you cannot install permanent weatherstripping, hang heavy thermal curtains that reach the floor, place heavy draft excluder cushions on the window sills, or apply clear heat-shrink insulation film over the entire window frame to trap a layer of dead air against the glass.
