Help! Tiled wetroom floor looks perfect but grout doesn't dry out!

[Paula]

I was looking at his pressure test , the way your plumber has had that rigged up its only testing the two outlets unless hes done the test from the main stopcock and not the actual shower valve , by using the main your actually testing the whole house but its the only way to test the actual shower valve unless youve access to the pipework,

Hi Kris

yes, you are right, but he took the faceplate off the main shower valve and inspected inside (it is buried in quite a large void in the wall) and there was no sign of any leakage from any of the pipes leading into it (I had a look myself). I can double check this with him, though if you think it's relevant.

Meanwhile, we'll carry on toasting the floor and see if it dries out!

 

[The D]

so how did he explain the patches outside the shower getting wetter even when there was no water touching the tiles or the grout or the drane ??

 

[Paula]

I was looking at his pressure test , the way your plumber has had that rigged up its only testing the two outlets unless hes done the test from the main stopcock and not the actual shower valve , by using the main your actually testing the whole house but its the only way to test the actual shower valve unless youve access to the pipework,

Just thinking about this, when you look at where the inlet pipes are in relation to the tiles, they are well behind the plasterboard and tiles. So surely if there was a leak here, then the water would be much more likely to run down the inside of the plasterboard and eventually through to the ceiling below, which definitely hasn't happened. As I said, there was absolutely no sign of leaking anywhere near the valve when we looked in the cavity.

 

[Dan]

And the waste wouldn't cause water to go above the tanking, and as you said, you'd see it in the ceiling below, eventually (at least by now anyway - some staining or something if not a full blown disaster type leak situation).

I'm absolutely baffled I must be honest.

But tiles don't cause water issues like that. It HAS to be something to do with the plumbing, somehow. I just can't think of anything.

The fact it was happening before the epoxy was installed, only means it has been pushed further into the bathroom, the epoxy hasn't fixed the issue per se. So it will still be a problem somewhere around the drain or shower heads. But if theres no sign of leaks there, then I can't see what it can be.

 

[The D]

you need to start removing tiles to see what is going on underneath

 

[Paula]

so how did he explain the patches outside the shower getting wetter even when there was no water touching the tiles or the grout or the drane ??

He was as perplexed as the rest of us! The only thing he could think was that there was still water trapped under the tray tiles from before the epoxy (our original grout still had damp patches after weeks and weeks of no use) and that this was now gradually working its way out beyond the shower tray (as it can't evaporate through epoxy, but can through the grout in the rest of the floor). Maybe it's not a steady process, and perhaps some days there is more evaporation than others (due to differences in humidity/full moon etc!!). But as Dan said, water is unlikely to travel uphill up the slope of the shower tray, isn't it?

That's why he said turn on the underfloor heating and see if we can get to a position of no wet patches, then try again.

 

[Paula]

you need to start removing tiles to see what is going on underneath

Which ones?

 

[The D]

for there to still be water that is just trapped under the tiles you must have had buckets full under there to start with and where did that come from if there was no obvious cracks or missing grout.

 

[The D]

Which ones?

start on the floor in the shower and work back

 

[Paula]

for there to still be water that is just trapped under the tiles you must have had buckets full under there to start with and where did that come from if there was no obvious cracks or missing grout.

Well if you remember there was quite a lot of missing grout around the drain, plus I think one of you spotted small cracks in some of the grout lines in the tray, so it could be that loads of water got in there during the six months or so we were using the shower every day?