How-To Guides
Sash Window Repair Guide: Cords, Weights, Pulleys and Draughts
28 March 2026
The double-hung sash window is an elegant piece of engineering: two sashes that slide vertically, each balanced by a hidden counterweight on a cord running over a pulley. When it works, it is effortless. When a single component fails, the whole window can stop functioning.
Cords and weights
The most common fault is a broken sash cord. When a cord snaps, its counterweight drops into the box frame and the sash no longer holds its position, it crashes shut or won't stay up. The fix is to open the frame, replace the cords with waxed sash cord, rematch the weights, and rebalance the sash.
Pulleys, beads, and binding
Worn or seized pulleys make sashes stiff, while parting beads and staff beads that have been painted over cause binding. Servicing the pulleys and renewing the beads lets the sashes run true again.
Draughts and rattles
Rattling and draughts come from gaps that have grown too large over time. Discreet brush or compression seals can be fitted during repair to stop both, without changing the look of the window or stopping it from opening. Done together, these repairs return a tired sash window to a smooth, quiet, weather-tight operation.
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