Fit locks to timber windows

Fit key-operated locks to timber casement or sash windows, keeping keys nearby in case you need to escape a fire.

WL-01Check your window type and buy the right lockTimber windows are either casement (hinged, opening outward) or sash (sliding up and down). Casement locks are a small key-turned snib fitted to the frame and stay; sash locks are a two-part screw-down bolt fitted where the two sashes meet. Check the timber is at least 20mm thick where the lock sits so the screws have something to bite into.

1 pack · Key-operated casement lock (pack of 2)

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2 each · Sash window lock (if fitting sash windows)

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WL-02Gather your toolsYou'll need a cordless drill with a 2mm pilot bit and a screwdriver bit to match the screws supplied, a pencil, a tape measure, masking tape, and a bradawl for starting screw positions in soft timber. Safety glasses are worth wearing, since old paintwork can flake when drilled.

1 each · 2mm HSS drill bit

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1 roll · Masking tape

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1 each · Bradawl

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WL-03Choose the position and think about fire escapePosition the lock where it's easy to reach with the window closed, usually on the opening edge for casements or where the two sashes overlap. If the window is a bedroom or the only escape route in a fire, don't rely on a key being locked away in a drawer elsewhere in the house.

RULES

KNOW THE RULES

Building Regulations guidance on fire escape says windows used as an emergency exit must be openable quickly by anyone inside. Keep the key on a hook right next to the window, not stored elsewhere.

WL-04Mark up and drill pilot holesOpen the window fully. Hold the lock body in place and mark the screw positions with a pencil, then do the same for the keep or striker plate on the frame. Stick a small piece of masking tape over each mark to stop the timber splitting, then drill a 2mm pilot hole about 15mm deep, taking care not to drill through to the outside face or into the glass rebate.

WL-05Fix the lock and keepScrew the lock body into its pilot holes first, then fit the keep or striker plate to match. Use the screws supplied with the lock rather than your own, as they're sized for the fixing holes. Don't overtighten — timber threads strip easily if you force the last turn.

1 set · Wood screws (supplied with lock)

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WL-06Test the lock and adjust if neededClose the window and turn the key. It should engage smoothly without you having to force it. If it binds, loosen the keep's screws slightly and nudge it a millimetre or two until the lock turns freely, then retighten.

WL-07Fit the remaining windows and tidy upRepeat the process for each window you're securing. Wipe away any wood dust or paint flakes from the sills, and vacuum the windowsill area. Hang a labelled key for each lock on a hook close to its window so everyone in the house knows where to find it.

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