Fit a wall-hung vanity unit to a metal stud wall — HomeGraft

Fit a wall-hung vanity to a metal stud wall using a timber noggin or pattress, then connect the tap and waste safely.

VN-01Prepare the area and isolate the waterClear everything from under the sink and lay a dust sheet on the floor. Find the isolation valves under the basin, or the main stopcock (usually under the kitchen sink), and turn the water off. Open the old tap briefly to check the supply is dead before you start any plumbing work.

1 each · Dust sheet

Buy:ScrewfixB&QToolstationAmazon

1 each · Bucket

Buy:ScrewfixB&QToolstationAmazon

1 each · Adjustable spanner

Buy:ScrewfixB&QToolstationAmazon

VN-02Work out what the wall is made ofRun a stud detector, or a strong magnet, across the wall in a horizontal line — a regular line of screw heads roughly 400mm or 600mm apart means plasterboard on studs. Tap the wall: a dull thud is a stud, a hollow sound is the gap between them. Drill a 3mm pilot hole in an inconspicuous spot — fine grey swarf means metal studs, wood dust means timber studs, and solid resistance with brick dust means masonry or dot-and-dab. This job assumes plasterboard on metal studs, but confirm it before you commit to any fixing.

1 each · Stud and cable detector

Buy:ScrewfixB&QToolstationAmazon

1 each · 3mm drill bit

Buy:ScrewfixB&QToolstationAmazon

VN-03Check for cables and pipes before you drill or cutCables and pipes can run almost anywhere behind a wall, not just in the usual safe zones, and a metal stud frame will confuse a cheap detector even further. Sweep the whole fixing area again, but still treat the wall as live until you've proved otherwise. If there's any doubt, isolate the relevant circuit at the consumer unit before drilling, and make sure the water is off at the stopcock before cutting into the wall.

VN-04Choose the right fixing for your wall typeA wall-hung vanity is heavy once it's full of water and takes a real outward pull every time someone leans on it — a metal stud and plasterboard alone will not hold that, and a toggle will eventually pull through. You need a timber noggin or an 18mm plywood pattress fixed between the studs with self-drilling stud screws, or a fixing through to solid masonry if it sits behind the wall. Never use a plain plastic wall plug or an ordinary wood screw in a metal stud — it strips straight through the 0.5mm steel. On solid brick or block, skip the noggin and use masonry bolts straight into the wall; on dot-and-dab, use fixings long enough to pass through the board and adhesive dabs into the masonry behind; on lath and plaster, avoid heavy fixings and fix into a timber batten screwed to the joists or studs behind it instead.

1 each · Timber noggin, 44x70x600mm

Buy:ScrewfixB&QToolstationAmazon

1 box · Self-drilling metal stud screws, box of 25

Buy:ScrewfixB&QToolstationAmazon

VN-05Cut in and fit the noggin or pattressMark the vanity's fixing centres on the wall, then find the two metal studs either side using your earlier test. Cut a section of plasterboard between the studs with a plasterboard saw, keeping the offcut to patch later. Screw a length of 44x70mm timber noggin, or an 18mm plywood pattress cut to fit, to the front edge of both metal studs using self-drilling screws so it sits flush with the board face. Screw the plasterboard offcut back over the noggin, then fill and sand the joint.

1 each · Plasterboard saw

Buy:ScrewfixB&QToolstationAmazon

1 each · Plasterboard offcut

Buy:ScrewfixB&QToolstationAmazon

1 tub · Filler

Buy:ScrewfixB&QToolstationAmazon

VN-06Mark and drill the fixing holesHold the vanity's fixing bracket or template against the wall, check it's level with a spirit level, and mark the hole centres over the new noggin. Drill through the plasterboard and into the timber noggin at the size stated by the vanity's fixing kit, usually 6mm to 8mm. Vacuum the dust out of each hole before fitting any screws.

1 each · Spirit level

Buy:ScrewfixB&QToolstationAmazon

1 each · 8mm drill bit

Buy:ScrewfixB&QToolstationAmazon

VN-07Hang the vanity unitGet a second person to help lift the unit, since it's awkward and heavy for one person. Drive the coach screws or bolts through the bracket and into the noggin, tightening evenly so the unit doesn't tilt. Check it's level again, then give it a firm push-and-pull test before you let go.

1 set · Coach screws or bolts, set

Buy:ScrewfixB&QToolstationAmazon

VN-08Connect the tapFit the tap to the vanity top following the manufacturer's instructions, using the washers and locknut supplied. Wrap PTFE tape around the tap tails, then connect flexible tap connectors to the isolation valves with compression or push-fit joints. Any new pipework and fittings must comply with UK water regulations.

RULES

1 each · Tap

Buy:ScrewfixB&QToolstationAmazon

1 roll · PTFE tape

Buy:ScrewfixB&QToolstationAmazon

2 each · Flexible tap connectors

Buy:ScrewfixB&QToolstationAmazon

1 set · Compression fittings

Buy:ScrewfixB&QToolstationAmazon

KNOW THE RULES

Water Supply (Water Fittings) Regulations 1999: new pipework and fittings must prevent contamination and waste — use WRAS-approved fittings and compliant joints.

VN-09Connect the waste trapFit the basin waste into the vanity's basin, sealing under the flange with the washer or plumber's putty supplied. Connect the waste trap underneath, making sure the pipe run has a slight fall towards the soil stack or drain. Hand-tighten the nuts, then give them a quarter turn with a spanner — don't overtighten plastic fittings.

1 each · Waste trap kit

Buy:ScrewfixB&QToolstationAmazon

VN-10Turn the water back on and testOpen the isolation valves and turn the water back on at the stopcock. Run both hot and cold taps for a minute and check every joint, including the waste trap, for leaks. Tighten anything that's damp, dry it off, then check again after ten minutes.

1 each · Cloth

Buy:ScrewfixB&QToolstationAmazon

VN-11Seal and tidy upRun a bead of silicone sealant along the join between the vanity and the wall, and around the basin edge if it's not integrated. Wipe away excess with a damp finger, then leave it to cure for the time stated on the tube before using the basin normally. Clear away dust sheets, offcuts and packaging.

1 tube · Silicone sealant

Buy:ScrewfixB&QToolstationAmazon

Some links may earn us a small commission at no extra cost to you.

Save this as a project

Back to all guides