ELECTRICAL BASICS

Replace a wall light fitting like-for-like

Swap an old wall light for a matching new one safely, checking wiring and wall type before fixing it securely.

WL-01Check the new fitting and gather your toolsBuy a replacement wall light with the same lamp type and a similar or lower maximum wattage than the old one. If the room is a bathroom, only fit a light with the right IP rating for its zone - Zone 1 and 2 need IP44 or higher near a bath or shower. Get a voltage tester, screwdrivers, wire strippers and a drill with a masonry bit and a wood/steel bit ready, in case you need new fixing holes.
RULES
1 each · Replacement wall light fitting
1 each · Voltage tester
KNOW THE RULES

Bathrooms are a Part P special location. A straight like-for-like swap of a fitting usually isn't notifiable, but if you're changing the circuit or the location, check with building control first.

WL-02Turn off the power and prove it's deadSwitch off the relevant MCB at the consumer unit - it's usually labelled 'lights' or 'lighting'. Tape over the switch or lock it off if you can, so nobody turns it back on while you're working. Touch your voltage tester across the live, neutral and earth at the fitting to confirm there's no power before you go any further.
WL-03Remove the old fittingUndo the screws holding the backplate to the wall and ease the fitting away. Take a photo of the wiring before you disconnect anything, so you know exactly how the terminals were connected. Loosen the terminals and free the wires, then check the flex and earth wire for any damage or discolouration.
WL-04Work out what's behind the wallWall lights are usually fixed to solid brick or block, but check if yours is on a stud wall. Run a stud detector or a magnet across the area - a magnet pulls towards the screw heads fixing plasterboard to a timber or metal frame. Tap the wall: a dull, solid sound means masonry behind, a hollow sound means a stud wall. A small pilot hole that brings out pale wood dust means a timber stud; fine grey swarf means metal.
WL-05Fix the new backplate to the wallBefore you drill anywhere, remember cables and pipes can run in places you don't expect - a detector helps but can miss cables that are deep, in conduit, or behind metal-backed board, and a metal stud frame can fool cheap detectors further. Find your stopcock (usually under the kitchen sink) and check it turns, so you can shut off the water fast if you hit a pipe; isolate the circuit at the consumer unit first if there's any doubt. In solid brick or block, drill a 6mm hole to 35mm depth, fit a red wall plug, and drive a 4x30mm wood screw. In plasterboard on timber studs, find the stud centre with a pilot hole and drive a 4x40mm wood screw straight in - no plug needed. In plasterboard on metal studs, never use a wood screw or plastic plug - they strip straight through 0.5mm steel; use a self-drilling metal-stud fixing or a toggle-type hollow-wall anchor rated for the fitting's weight. Through dot-and-dab, use a long fixing (75-90mm) that passes through the dab and bites into the masonry behind. On lath and plaster, screw into a lath if you can find one, or use a spring toggle rated for the weight, since old lime plaster alone won't hold a screw.
1 pack · Red wall plugs (pack)
1 pack · 4x30mm wood screws (pack)
2 each · Self-drilling metal-stud fixings
2 each · Spring toggle fixings
2 each · Long fixings for dot-and-dab (75-90mm)
WL-06Wire in the new fittingMatch the new wiring to your photo: live (brown) to L, neutral (blue) to N, and earth (green/yellow) to the earth terminal. Strip back about 10mm of insulation if you need to shorten the wires, leaving no bare copper showing outside the terminal. Use a terminal block if the new fitting's tails are shorter than the original wiring. Tuck everything in neatly so no wire gets trapped against the wall or backplate.
1 each · Terminal connector block
WL-07Fit the light and check the connectionsOffer the new fitting up to the backplate and secure it with the screws supplied. Check it sits flush and doesn't rock or wobble on its fixings. Give each wire a gentle tug to make sure none has pulled loose from its terminal.
WL-08Restore power and testSwitch the MCB back on at the consumer unit, then switch the light on at the wall. Check it comes on cleanly, without flickering or tripping the circuit. If it trips straightaway, switch off again and recheck your wiring before trying a second time.
WL-09Tidy upFit the bulb and any shade or diffuser. Dispose of the old fitting and packaging responsibly - some old fittings contain electrical parts that shouldn't go in general waste. Sweep up any drilling dust and wipe down the wall, then put your tools away.
1 each · LED bulb (matching fitting)

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