Floating shelf to support a basin

[Tykey]

Evening all. Not sure if this should be a plumbing/tiling/plastering query, so I've put it in general in the hope someone can help.

I'm currently redoing our en-suite, and the missus saw a nice floating shelf with basin that she took a fancy to. The wall that this is to be attached to is stud and board, but it has been reboarded as when the precious tiles came off it made a right mess of the walls.

Of course the brackets didn't fit nicely to where the studs were located, so before it was boarded a couple of noggins were put in at the right height.

Fast forward a couple of weeks, and I've cut notches out of the plasterboard and attached the floating shelf bracket to the noggin using the massive screws supplied with the shelf.

However, I was sceptical that even attached in this way, it would be able to support the weight...lo and behold, when I slot the shelf on and just rest the basin on it, there's a noticeable sag. It seems as though the noggin itself is twisting slightly downwards, which is where the sagging is coming from.

Does anyone have any tips or advice for how this can be cured? Can a noggin be "strengthened"? Or is it just a case that I tell the missus we need a normal vanity unit to put under to support the shelf?!

Thanks in advance.

 

[foxhole]

You could pack behind the bracket to level it , though it would have been better to ply the area and spread the load evenly .

 

[big-all]

just to check this is a floating shelve specifically designed to take the weight off the basin you have ??
if so contact the manufacturer and ask there suggestion for wall construction suitable for the weight
are the studs you have at say 400mm centers and 102 ish or a minimum 89mm timbers ??

 

[Tykey]

You could pack behind the bracket to level it , though it would have been better to ply the area and spread the load evenly .

Thanks. I did think about trying to put something behind the bracket to pack it out a bit, but I was concerned about how that would hold up in the long-term. Once the brackets are in place I'll be tiling around it, so if it slips further there's the potential it could crack/push some tiles off.

Could I retro-fit some ply perhaps? Remove a section of the plasterboard, cut the ply to fit and attach to a couple of additional noggins, then re-fit the plasterboard on top?

just to check this is a floating shelve specifically designed to take the weight off the basin you have ??
if so contact the manufacturer and ask there suggestion for wall construction suitable for the weight
are the studs you have at say 400mm centers and 102 ish or a minimum 89mm timbers ??

Yes, the shelf is designed to go with the basin. The instructions specify that "For stud walls it is essential that the shelf is supported by a fully battened stud partition". The studs are at 400mm centres, although one of them is only 360 as it's the final stud in the wall.


I did some quick calculations, and the shelf is 8kg, the basin 11.2kg, the taps 1.3kg, and if the basin is pretty full to capacity with water that's another 10kg, so the brackets need to support about 30kgs there or thereabouts.

 

[foxhole]

A piece of 18mm ply would certainly make fixing easier and secure .

 

[Tykey]

Having just re-done the subfloor with 18mm ply + hardiebacker I have some left over, so I'm going to try that.

I'll cut out a section of plasterboard, insert a load of noggins, screw ply to the noggins, screw the section of plasterboard back to the ply and studs, and then re-try the brackets going through the ply and the noggins.

Failing that, I'm telling the missus she needs to choose a vanity unit to go under the shelf!!

Thanks.

 

[Deleted member 174758]

I'm with Foxhole - this needs 18mm plywood and ideally it needs to be 300 to 400mm high so that you can spread the load over a goodly area (with metal stud this will be even more important). If you have a decent plywood patress you don't need noggins

 

[Tykey]

Thanks for all the input on this.

I went with a belt and braces approach. I removed the plasterboard, left the biggins, and added 500mm of 18mm ply before refitting the plasterboard.

The brackets are now attached to the ply, and it certainly seems able to support a lot more weight now.