ᐅ Sink mounted to squared timber using a hanger bolt

Hello everyone,

we are currently renovating the bathroom of our older building.
Due to the thin walls (the bathroom is in a dormer), the water supply and drainage pipes (both new) for the washbasin are surface-mounted on the wall.
We now want to build a stud wall in front of it ourselves. Since the bathroom is very small (5 m2 (54 sq ft)), every centimeter counts, so the stud wall should be as shallow as possible.
The plan is to screw four rows of 44 mm (1.7 inch) thick squared timber beams to the wall and then cover them with 15 mm (0.6 inch) OSB and 10 mm (0.4 inch) Fermacell boards.
The stud wall will be about 1.6 m (5 ft 3 in) long, 1.2 m (3 ft 11 in) high, and with tiles at the end approximately 90 mm (3.5 inches) deep.

Now the question is how best to hang the washbasin (mineral cast with cabinet).

My idea was to make sure that, at the height where the basin will hang, there is definitely a timber beam installed so that later two M10 hanger bolts can be screwed into the wood to hang the basin. The load-bearing section would then be about 60 mm (2.4 inches) thick (44 mm squared timber + 15 mm OSB).

I can’t say exactly how heavy the basin is at the moment. It is definitely mineral cast (so rather lighter than ceramic) and measures 70 x 45 cm (28 x 18 inches).

Do you think two hanger bolts anchored in 6 cm (2.4 inches) of wood can safely support the basin?

Best regards,
Simon

The drywall installer and plumber both assured me that even 25mm (1 inch) gypsum board can hold 50 kg (110 lbs) per screw.

So, I wouldn’t be too concerned about your construction setup.

Hmm, 50 or 100 kg (110 or 220 lbs) can add up quickly when there is water in the sink and maybe a child hanging on as well. 🙂

If the panels are standing on the floor, they will hold up easily, even with water, a child, and an adult. For 15mm OSB and 10mm Fermacell, I would use 10mm holes with 10mm anchors and 6 to 8mm screws, for example, UX screws from the Angler.

ismon_rlp schrieb:

Hmm, 50 or 100 kg (110 or 220 lbs) can add up quickly when there’s water in the sink and maybe a child hanging on it. 🙂

Per screw. If you use six screws, three at the top and three at the bottom. You just need to use proper cavity anchors or your threaded system.

I didn’t want to use anchors in this case. I would have used a 160mm (6.3 inches) hanger bolt for wood—so a wood screw thread on one end and an M10 thread on the other. The wood thread would have been screwed directly into the 60mm (2.4 inches) timber. There is no cavity in this part of the construction.

Or would it be better to create a cavity where the sink is mounted and then use cavity anchors there?