OUTDOOR & GARDEN

Fit a wall-mounted letterbox to an exterior brick wall

Mount a letterbox securely on an exterior brick wall, checking for hidden cables and pipes before drilling.

LB-01Gather your tools and check the kitUnpack the letterbox and check it comes with masonry fixings — if not, you'll need your own screws and plugs. Lay everything out on a dust sheet under the work area. You'll need a hammer drill, masonry bit, spirit level, tape measure and pencil.
1 each · Wall-mounted letterbox
1 each · Dust sheet
1 each · Spirit level
1 each · Tape measure
1 each · Pencil
LB-02Choose the position and mark it upPick a spot around 1.3-1.5m from the ground — comfortable to reach and easy for a posted letter to fall through without jamming. Hold the letterbox against the wall, check it's level, and mark through the fixing holes in the backplate with a pencil.
LB-03Check for hidden cables and pipes before drillingRun a cable and pipe detector over every marked point before you touch the drill. Even with a clear reading, still assume something could be there — detectors miss cables that run deep, in conduit, or outside the usual safe zones. Find your stopcock now (usually under the kitchen sink) and check it turns freely, so you can shut off water fast if you hit a pipe. If you have any doubt at all, isolate the relevant circuit at the consumer unit before drilling.
1 each · Cable and pipe detector
LB-04Drill and plug the fixing holesFit a 6mm masonry bit and set the drill to hammer mode. Drill each marked hole to 45mm deep, keeping the drill square to the wall. Blow or vacuum the dust out of each hole, then tap in a 6mm x 40mm wall plug flush with the brick face.
1 each · Masonry drill bit, 6mm
1 pack · Wall plugs, 6mm x 40mm (pack of 10)
LB-05Fix the letterbox to the wallHold the letterbox back in place and drive a 50mm No.8 screw into each plug, starting by hand until it bites, then finishing with a drill driver on a low torque setting. Don't overtighten — stop once the letterbox sits snug against the brick. Recheck with the spirit level before fully tightening the last screw.
1 pack · Screws, 50mm No.8 stainless steel (pack of 10)
LB-06Weatherproof the fixing and test itRun a thin bead of exterior silicone sealant along the top edge of the backplate where it meets the brick, to stop rainwater tracking in behind it. Open and close the flap a few times to check it moves freely, and test the lock if it has one. Wipe away any excess sealant with a damp cloth.
1 tube · Exterior silicone sealant
LB-07Tidy upFold up the dust sheet away from the house to avoid brick dust getting trodden inside. Sweep or vacuum any dust from the wall and ground below. Bin the packaging and check the letterbox once more for a level, secure fit.

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