Draught proofing
Warm rooms without losing your original windows
A routed brush-pile system fitted into the sash itself — invisible from the room, and reversible.
Why sashes leak
A sash window has to slide, so it is built with clearance. Add a century of shrinkage and worn parting beads and that clearance becomes a continuous gap running the height of the window on both sides.
Sealing it with foam strip stops the window opening. Routing a brush pile into the sash edge closes the same gap while leaving the window working exactly as it should — and it can be taken out again without a trace.
- Up to a 60% cut in draught losses through the window
- Noticeably less traffic noise from the street
- No more rattling in high wind
- Sashes run more smoothly, not less
- Completely hidden once the beads are back on
- Nothing irreversible — original joinery is retained
The process
Five steps, usually one day
Survey
We measure each sash, check the cords and note where the gaps actually are.
Strip out
Beads eased off, sashes removed, old paint and staples cleaned from the running surfaces.
Rout and seal
A fine groove is routed into the sash edges and brush pile is fitted into it.
Rebalance
Cords checked or renewed and weights re-matched so the window still holds at any height.
Refit and test
Beads refitted with a parting-bead seal, the window tested open and closed, room left clean.
Guide pricing
Draught proofing from £240 per sash window, including cord check and rebalance. Whole-house rates available.
Book a draught-proofing survey
Send us a photo of the window and we will usually come back the same day with an honest idea of cost.