Sink coming away from wall, suitable filler?

[naughtyneck]

Hi

Big DIY noob here so please excuse my ignorance. We have a pedestal sink in and the bracket on one side of the wall has completely come away due to the wall crumbling away around the fittings. Additionally where the back of the sink was attached to the wall that has come away pulling the thin layer of plaster off around it. So we have a sink attached to the wall on one side and being held up by the pipes coming out the floor. There is no ceramic surround around the pipes - its just a sink with bare pipes coming out the bottom. We can add temporary support to it but obviously this still needs fixing!

The wall has crumbled away around the fixings appears to plaster and some other material, the bigger of the two holes is probably an inch deep and crumbles away relatively easily if I dig around in there with my finger.

So I figure I need some sort of super strong filler that I can use to fill these holes and then screw into and re-attach the bracket. Then around the back of the sink some sealant, but perhaps before that something to replace the thin layer of plaster that has peeled away where it detached.

My question is am I assuming correctly and if so can anyone advise what sort of products I should be looking for? At this stage I'm not looking for an awesome finish, the room is in dire need of decoration so I can deal with that later. We just want the sink attached safely.

Cheers

 

[alan333]

If the plaster is already crumbling IMHO you'll not get a decent fix to it, even after you fill it. What's the wall made from? You really need a fix into the wall, not just the plaster stuck to the wall. Another idea (if you've got the space) is to fix a strip of plywood or similar to the whole area behind the sink and fix your sink to that.

 

[PrenticeBoyofDerry]

Sounds like the plaster is failing, you can bodge it up as much as you wish but it is always going come back and haunt you.
The plan would be to isolate water to sink and remove it, repair wall behind sink with bonding coat and skim, leave to cure, then refix, but this time drive plugs into solid wall rather the just into plaster a bead of silicon can be applied between wall and sink, as an added moisture barrier but not as a functional fixing for sink.