Soggy worktop behind kitchen sink

I think I would be more concerned where the water is getting through to cause such damage and get it sorted first everything else is just a sticking plaster.

Richard

I'm 99% sure that the wetness is due to my over enthusiastic washing up. My plan is to mosaic tile over the repaired area. This, with the intention of waterproofing against further splashes. I didn't want to enlarge the original question by bringing up the tiling aspect of the plan, but as you now ask...

Well that changes everything. Hack the lot out and replace it with a bit of plywood or chip or mdf

Why not support it from underneath ?

With a solid material that is not squelchy.

------------------------ Final stick pushing up under the work | | ------------- | Sticks of thin stock, to make a pusher | --- =--/ \--- Car scissor jack, flush to wall \___/ rotated so you can get at the nut

The car scissor jack, is to make the bodge adjustable, and you can vary the pressure underneath, to get a result. The "U" shaped section in the diagram, is so only one scissor jack is required. It's still going to be difficult to adjust.

An injected liquid won't work, because of the amount of pressure required to inject it. The pressure would likely cause the top of the work surface to separate from the rest of the materials.

When we needed to inject some materials at the factory at work like that, there was a metal plate for the injection port that would accept a considerable amount of pressure.

All that you need, is some experience with caulk tubes and material going past the piston, to know what "too much pressure needed" is like :-)

Paul

If you really want to do that, then maybe a resin cartridge for the installation of fixings in concrete. Go to Screwfix's website and use their search for "resin" to see some examples.

However, as otherwise said, fix the problem...

My hacking is not very subtle or precise, that's why I went down the filler avanue.

I have the greatest admiration for you expertise and skill in these things. Unfortunately, I cant really get at it from underneath.

That's my hope and intention. Not only that, I quite like the method you suggest. Screwfix here I come.

It wouldn't take long to remove the sink by undoing the pipes and lift up. You'd then have all the access you need to remove the soggy wood, salvage the resin top and make good with another piece of wood.

Then do a good job sealing everything, including the bare cut wood joints before refitting the sink.

If the tap hookup is with flexible tubing and not soldered into place, the trap can be undone on the sink and it should not be too traumatic to work on.

With the description of wetness involved, I'd assume something is leaking at plumbing level, rather than just runoff. I'd be looking for a puddle underneath the sink... or lower. Maybe some of the kit purchased for the project is leaking.

And if you use silicon seal around the sink, don't get carried away. Design the application such that it can easily be cut away with a knife later. If you slather the stuff on and then lower the sink into it, the adhering surface could be so large, you'll never get the sink up again off the surface. Then it'll take an electric jig saw and cutting all around the sink, to get it apart.

Paul

Be absolutely certain you know what the source of water is, before deploying your "fix". If it's an actual plumbing fixture leak, you'll regret pouring stuff all over the place. For building materials to get soggy, that must have taken a lot of water, not a little.

Paul

I'm intrigued, what on earth happened to do this to the worktop. Surely some leak or ingress path from above has to be present, so fixing it is only ever going to be a bodge. One needs to find out why and fix it. Brian

And of course it is often best to inject the resin before you clamp it up, and that way it will be all through the damaged area as you squeeze it. Brian

If you are going to change the finish, Why not gouge out the dodgy stuff and replace it with something less prone to water damage and then tile over that. Tiles do not like what they are stuck to to flex or expand and slump. Brian

Let it dry for a few days, score the top and or bottom then carefully remove the debris and seal with something suitable. I think you can also use a couple of plates underneath to make sure the piece fitted in is firm. May moons ago I did this sort of thing and with some sealant and patience, it could be overlaid with a suitable surface that was actually better than I had expected. Did not use mosaic though, think it was just a piece of hard plastic of some kind glued on. Brian

Thanks for all the great advise from group members.

I'm certain that the soggy area of worktop is from splashes from the sink, made worse by badly sealed edges.

I'm going to pull up the sunken surface and fill the voids beneath by injecting filler, then tile over.

If that fails I'll take the sink out and do a more extensive repair.

I think that will work, try and getr rid of all the soggy wood