Fit a letterbox cage or guard

Fit a letterbox cage inside your front door to catch post safely, choosing fixings that suit your door material.

LC-01Check the door and buy the right cageWork out what your door is made of: solid timber, a composite door (a GRP or wood-effect skin over a foam or timber core), or uPVC/metal with a steel reinforcing box inside. Most letterbox cage kits come with fixings for timber and composite doors as standard, plus extra bolts for uPVC. Buy a cage sized to fit your letterbox aperture, with a depth that clears any door furniture on the inside.

RULES

1 each · Letterbox cage/guard kit

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KNOW THE RULES

If this is a communal fire door in a block of flats or HMO, check with your landlord or freeholder before fixing anything to it. Fire doors have to keep their certified fittings under UK fire safety rules, and drilling extra holes can affect that.

LC-02Remove the old letterbox flap if you're replacing oneOpen the letterbox flap and unscrew it from the inside, keeping the screws in case you need them later. Wipe away any old paint flakes or dust around the aperture. If there's no existing flap to remove, just clean the area where the cage will sit.

1 each · Screwdriver (matching existing screws)

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LC-03Position and mark the cageHold the cage over the letterbox aperture on the inside of the door and check it sits square, with the opening lined up so post drops straight in. Open the letterbox flap fully and make sure it swings clear of the cage without catching. Mark the fixing hole positions with a pencil through the cage's mounting holes.

1 each · Pencil

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1 roll · Masking tape

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LC-04Drill the fixing holes for your door typeTimber door: drill a 2-3mm pilot hole at each mark, about 2mm shallower than the screw length, to stop the wood splitting. Composite door: drill carefully through the outer skin using the same size pilot hole, then use the longer screws supplied (usually 30-40mm) so they bite into the solid core behind. uPVC or metal-reinforced door: drill through with the bit size stated in the kit instructions and fit the through-bolts provided rather than self-tapping screws, since screws can strip the thin metal box section inside. Wear eye protection, as drilling uPVC and metal throws off sharp swarf.

1 each · Drill/driver

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1 set · HSS drill bit set (metal/uPVC)

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1 each · Wood drill bit (timber doors)

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1 each · Safety glasses

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LC-05Fix the cage in placeTimber and composite doors: drive in the screws supplied with the kit, tightening evenly so the cage sits flat against the door. uPVC and metal doors: fit the through-bolts from the outside, add the nuts on the inside and tighten evenly by hand plus a quarter-turn with a spanner, without overtightening, as squeezing the uPVC skin can crack it. Check the cage doesn't twist or sit proud at any corner.

1 set · Screws/bolts (as supplied with cage kit)

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1 each · Spanner (for uPVC through-bolts)

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LC-06Test the letterbox flap and cageOpen and close the letterbox flap several times from outside to check it moves freely and doesn't snag on the cage. Post a piece of card or an old envelope through to confirm it drops cleanly into the cage rather than jamming. Check there's no gap large enough for fingers to reach through and unlock the door from outside — that's the main point of fitting a cage.

LC-07Tidy upVacuum up any drilling dust or swarf from the floor and door threshold, especially small metal shavings from uPVC or metal doors, as these can mark carpets or feet. Wipe the door clean and dispose of the packaging.

1 each · Vacuum cleaner

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1 each · Cloth

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