What is a draught strip?
A draught strip is a sealing profile fitted in the rebate of a window or door to close the gap between the sash or door leaf and the frame. It keeps out cold air, noise, dust and insects, and is one of the cheapest and quickest ways to reduce draughts and heat loss.
Types
- Foam strip: cheap and easy, but short-lived. Suitable as a temporary fix.
- Rubber or EPDM profile: available in shapes such as P, E, D and V, each for a particular gap size. Lasts much longer.
- Silicone profile: stays flexible for a long time, even in the cold.
- Brush strip: for sliding doors, sash windows and under doors.
- Groove-fitted profile: a profile with a foot that is pressed into a routed groove in the frame. More durable than self-adhesive strips.
Choosing and fitting the right strip
- Measure the gap: press a piece of modelling clay wrapped in cling film onto the rebate and close the window or door. The thickness of the impression is the gap size.
- Match the profile to the gap: the strip should be slightly compressed, not squashed flat. Too thick, and the window closes badly and the hardware is overloaded.
- Prepare the surface: clean, dry and grease-free. Do not fit self-adhesive strips in freezing weather.
- Apply: in full lengths, with neat mitred or tightly butted corners. Do not stretch the strip, or it will shrink back.
- Test: trap a sheet of paper between window and frame. If it pulls out without resistance, the seal is not working there.
Common mistakes
- Sticking the strip in the wrong place in the rebate, so it rubs against the sash.
- Taping over or blocking ventilation openings. Draught-proofing does not replace ventilation.
- Leaving old, hardened strips in place. Check them every few years.
Related terms
- Draught
- EPDM
- Hardware/ironmongery
- Window frame
- Airtightness
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