Replace a basin mixer tap

Swap an old basin tap for a new one safely, without leaks, in a single session under the basin.

RT-01Get set up and protect the areaClear everything out from under the basin and lay an old towel down to catch drips. Have a bucket and torch to hand so you can see and reach the pipework. Check you can get a basin wrench or tap back-nut spanner under the basin — space is often tight.

1 each · Basin wrench (tap back-nut spanner)

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1 each · Bucket

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1 each · Old towel or rags

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RT-02Turn off the water supplyClose both isolation valves under the basin — turn the slot a quarter turn until it's crossways to the pipe. If there are no isolation valves, turn off at the stopcock, usually under the kitchen sink. Open the tap fully to drain the remaining water into your bucket.

RT-03Disconnect the old tapUndo the flexible tap connectors where they meet the isolation valves, letting any last water drip into the bucket. Reach up under the basin and loosen the tap's fixing nut with the basin wrench, then lift the old tap out from above.

RT-04Clean the basin and check the holesWipe away old sealant, limescale and grime around the tap holes so the new tap sits flat and seals properly. Check the basin isn't cracked or chipped around the tap holes — a hairline crack here can widen once a new tap is tightened down.

1 each · Limescale remover or mild cleaner

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RT-05Fit the new tapPush the new tap's tails down through the basin holes with the supplied rubber washer or seal in place underneath. From below, fit the fixing plate and nut and tighten by hand first, then a little more with the wrench — snug, not overtightened, or you can crack the basin.

1 each · Basin mixer tap

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RT-06Connect the flexible tailsFit new flexible tap connectors between the tap tails and the isolation valves rather than reusing old ones, which can fail at the joint. Wrap the threaded ends with PTFE tape before tightening, using the compression or push-fit method you already know.

RULES

2 each · Flexible tap connectors (300mm)

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1 roll · PTFE tape

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KNOW THE RULES

Under the Water Supply (Water Fittings) Regulations 1999, any tap or connector fitted must be WRAS-approved. Buy tails and taps marked WRAS-approved.

RT-07Turn the water back on and check for leaksOpen both isolation valves slowly rather than all at once — this stops a rush of water shocking the new joints. Check every connection you made with your fingers, feeling for damp rather than just looking. Leave a dry sheet of paper under each joint for 30 minutes and check it stays dry.

RT-08Test the tap properlyRun the hot and cold separately for a minute each to clear any debris from the new fitting and check flow and temperature feel normal. Check the plug and waste still seal and drain as before. Recheck all joints once more before you finish.

RT-09Tidy upDry off the basin and cupboard, and put back everything you cleared out. Take the old tap and any packaging to be recycled or disposed of properly — old taps often contain brass and can be scrapped rather than binned.

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