Why Your Aluminium Window Rattles, and How to Fix It

Diagnose before you buy

A rattling window has four common causes, and they need four different parts. Buying the wrong one is easy and avoidable.

Push the closed panel gently with a flat hand and feel where the movement is.

Cause one: the lock is not pulling tight

If the panel moves in and out against the other sash, the lock is the problem.

A crescent lock works by rotating a cam that draws the two sashes together and holds them under tension. When the cam wears, or when the lock was never adjusted after the frame settled, it engages without actually tightening.

A touch lock does not draw the sashes at all — it catches them. That is its known trade-off, and on an exposed window it will always allow more movement than a crescent.

Fix: replace the crescent lock, or move from a touch lock to a crescent on a window that faces weather.

Cause two: the seal or brush has perished

If the movement is small but the noise is significant, particularly a buzzing rather than a knock, the weather strip or track brush has compressed or fallen out.

That brush is not decorative. It fills the gap the panel travels in, and it damps the small vibration that wind sets up. Once it is gone the panel has nothing to bear against.

Fix: a new track brush (SA-1 or SA-2) or an EPDM gasket.

Cause three: the roller has worn down

If the panel can be lifted or rocked vertically in its track, the rollers have flattened and the panel is sitting lower than it should. It now has clearance in the channel that it did not have when new.

You will usually have noticed the window getting heavier to slide before the rattle started — the two symptoms share a cause.

Fix: new rollers, replaced in pairs.

Cause four: the panel has come out of adjustment

Some sliding systems have an adjustment screw on the roller carriage that sets the panel height. If that has backed off, the panel drops and picks up the same clearance as a worn roller.

Fix: adjustment, no parts needed. Worth checking before buying rollers.

Start with the cheapest check

Clean the track first, dry, with a brush. Then check the adjustment screws if your system has them. Both are free.

If the window still rattles, work through the list above. Most rattles are the lock, and a lock is an inexpensive part.

Before the monsoon, not during

A window that rattles is also a window that leaks, because the same gap admits both wind and driven rain.

If you can hear a window in ordinary wind, deal with it before the monsoon rather than during. Dry weather is when the diagnosis is easy and the fix is cheap; the same job during heavy rain usually turns into a conversation about water damage as well.

If you are unsure which of the four you have, photograph the lock and the roller with the panel removed and send them on WhatsApp. That identifies it in a minute.