Hartwell Sash ยท London

Sash Cord
Replacement & Repair

Windows that slam shut, won't stay open, or drop suddenly โ€” usually a broken or worn sash cord. Repaired properly in a single visit, across London.

1 day Completed in one visit
Both Cords replaced as standard
Free Survey & no obligation
Up to 5yr Workmanship guarantee
What We Do

What is a
sash cord?

A sash cord is the rope or cord that connects each sash to its counterweight inside the window frame. When it's working correctly, you can raise and lower the window smoothly and it stays open at any height.

Over time โ€” usually after 20โ€“40 years โ€” the cord frays and snaps. The window either drops suddenly, won't stay up, or the sash becomes impossible to open. It's one of the most common sash window problems, and one of the most straightforward to fix.

We replace both cords on both sides as standard โ€” not just the broken one. If one has snapped, the other is usually close behind. We also inspect the pulleys, weights and beads while the sash is out, and flag anything else that needs attention.

How we do it โ€”
step by step

Every cord replacement follows the same careful process

01

Staff beads carefully removed

The internal staff beads are taken off cleanly โ€” no damage to the surrounding plaster or architrave.

02

Both sashes removed from the frame

Upper and lower sashes are taken out and set aside safely for inspection.

03

Weight box opened and weights inspected

Cast iron weights are checked, cleaned and confirmed to be the correct weight for the sash. Incorrect weights cause the same problem to return.

04

Both cords replaced โ€” all four in total

Quality waxed sash cord fitted on both sides of both sashes. We never replace just the broken cord.

05

Pulley wheels cleaned and oiled

Pulleys are checked for smooth running. Stiff or seized pulleys accelerate cord wear โ€” we address them at the same time.

06

Sashes re-hung, balanced and tested

Both sashes re-hung, the window tested for smooth, balanced operation. Staff beads replaced cleanly. Area left tidy.

Signs your sash cord
needs replacing

โ†“

Window drops suddenly

The cord has snapped and the sash is no longer supported. Common โ€” and dangerous if the window is heavy.

โŸณ

Won't stay open

The cord is fraying or has lost tension. The window slides back down when released.

โŠก

Only one sash moves

If the upper sash is stuck and only the lower moves, a cord failure in the upper is likely.

โ‰‹

Window feels unbalanced

Cord still intact but stiff, heavy on one side, or difficult to open โ€” early signs of wear before a full snap.

โˆฟ

Rattling or knocking sound

A fraying cord inside the weight box can knock against the frame as the window moves.

โŠ 

Window tilts to one side

One cord has failed while the other holds โ€” the sash leans or jams in the frame.

โš‘

We always replace both cords on both sides

It's tempting to replace only the snapped cord. But sash cords wear together โ€” if one has gone, the other is usually close behind. Replacing both in a single visit costs a little more upfront and saves a second callout within months. That's how we work.

Sash cord broken?
We'll fix it properly.

Send us a photo of the window โ€” we'll come back with a clear price, usually the same day. Most repairs completed in a single visit across London.