Short answer: measure the cabinet width you can fit, then subtract clearance. A wall-hung vanity needs the waste and water points set out before the cabinet is ordered, so measure the plumbing rough-in first and the cabinet second.
Most vanity returns come from one of three measurements being taken after the cabinet was ordered rather than before. This is the order to take them in.
1. Measure the available width first
Measure wall to wall at the vanity position, then again at floor level and at bench height. Old walls are rarely parallel. Use the smallest of the three numbers, then allow clearance on each side so the cabinet is not a friction fit.
2. Check the door and drawer swing
A vanity that fits the wall can still be unusable. Check that the bathroom door, the shower door and the vanity drawers do not collide. Drawers need their full extension clear of the door arc.
3. Locate the plumbing rough-in before ordering
The waste outlet position decides whether a wall-hung cabinet works without modification. Measure from the finished wall to the centre of the waste, and from the finished floor to the centre of the water points. Give those numbers to your plumber before the cabinet is ordered, not after it arrives.
4. Confirm the benchtop overhang
Stone and ceramic tops usually overhang the cabinet. The top, not the cabinet, is what has to clear the wall and the door.
5. Allow for the skirting
A floor-standing vanity pushed against a wall with skirting will sit proud of the wall by the skirting thickness. Either scribe the skirting out or allow for the gap in your setout.
Frequently asked questions
Wall-hung or floor-standing?
Wall-hung makes the floor easier to clean and suits smaller rooms, but needs noggins in the wall and the plumbing set out to suit. Floor-standing is more forgiving of existing plumbing.
What clearance should I leave either side?
Enough that the cabinet is not forced into the opening and the doors clear the adjacent wall. Confirm the exact allowance with your installer, since it depends on wall square and the cabinet's door style.
Can I use a wall-hung vanity on a stud wall?
Yes, with appropriate noggins installed before the wall is sheeted. Retrofitting support after the wall is closed means opening it again.
Does the tap go in the benchtop or the wall?
Either, but it must be decided before the top is ordered. A benchtop with no tap hole cannot be drilled on site if it is stone.
Not sure about your setout?
Bring your measurements to the Besten Home showroom at 283A Victoria Road, Rydalmere NSW 2116 and our team will check them against the cabinet you are considering before you order.