Leaking underfloor pipes?

[Tomily]

I have a newly laid underfloor heating system under screed and then tiled. I waited 2 days as requested by the tiler before turning the heating on. When I turned it on yesterday, patches of the grout started to get wet around the rooms (extension and utility). I turned it off last night and there was no change this morning. I put it back on this morning and it has got a lot worse, now also starting to get wet in the kitchen area too. It's not just damp either, it's quite soaking. The plumber thinks (as there is no pressure drop) that it can't be a leak, but must be moisture from the screed finding its way out due to the heat. No one seems to have an idea what it could be - builder, plumber, tiler. Could there be any other alternatives? I'm really worried it is going to trash my new kitchen

 

[lame plumber]

screed takes time to dry out, if you have tiled over recently laid screed the only way moisture can escape is through the grout!!!!!!!!! shouldnt tile on fresh screed, your tiler should know that!

 

[Tomily]

screed takes time to dry out, if you have tiled over recently laid screed the only way moisture can escape is through the grout!!!!!!!!! shouldnt tile on fresh screed, your tiler should know that!

I did question them about that but was told by builder and tiler that it was fine to tile on after 3 days, they used some piped in screed that dried fast?

So if that is the cause (which is much better than a leak!), would it be that wet not just look damp? And how long do you think it will take to dry properly, and should I put the heating on or not? Many questions thanks for your advice

 

[Ermintrude]

screed takes time to dry out, if you have tiled over recently laid screed the only way moisture can escape is through the grout!!!!!!!!! shouldnt tile on fresh screed, your tiler should know that!

Dry screed at 1mm per day! So 75mm = 75days.

U can force gravlon dry after a week . 1c aday rise in flow temp 65mm will take 4.5 weeks

 

[Tomily]

So clearly it has not been given anything like that amount of time. Given the situation I have, what is my best approach now? Do I leave the ufh off for few weeks? Or should I have it on a low as it will go?

 

[Gray0689]

I have a newly laid underfloor heating system under screed and then tiled. I waited 2 days as requested by the tiler before turning the heating on. When I turned it on yesterday, patches of the grout started to get wet around the rooms (extension and utility). I turned it off last night and there was no change this morning. I put it back on this morning and it has got a lot worse, now also starting to get wet in the kitchen area too. It's not just damp either, it's quite soaking. The plumber thinks (as there is no pressure drop) that it can't be a leak, but must be moisture from the screed finding its way out due to the heat. No one seems to have an idea what it could be - builder, plumber, tiler. Could there be any other alternatives? I'm really worried it is going to trash my new kitchen

The plumber should of had the underfloor pipe pressurised when screed was being laid
And laying tiles on wet screed is just silly the only way to get moisture out is out of grout as said and will leave white marks all over it
Best thing to do is late up the tiles and let the floor dry
I know it's not what you wanted to hear

 

[Toxic Ted]

How long did you leave the screed to dry before tiling?

 

[Tomily]

The plumber should of had the underfloor pipe pressurised when screed was being laid
And laying tiles on wet screed is just silly the only way to get moisture out is out of grout as said and will leave white marks all over it
Best thing to do is late up the tiles and let the floor dry
I know it's not what you wanted to hear

Is there no alternative? Can I not just leave it switched off for a few weeks to slowly seep out?

 

[Tomily]

How long did you leave the screed to dry before tiling?

It was for less than a week. Both builder and tiler said it was enough

 

[oz-plumber]

First, I would have the UFH tested and left under pressure for a few days to see if there is any pressure drop. Do not rely on the boiler pressure gauge - disconnect piping from boiler.

If there are no leaks detected then try and run the UFH system at @ 30C and see if the water dries up. There may be moisture in the screed still. In that case you do not want to have the screed heated with 50C water, it may cause problems with it drying out too quick.

If the UFH system is not leaking, then you may have greater problems with tiling over a screed with that much moisture seeping through the grout / tile joints

 

[Gray0689]

It was for less than a week. Both builder and tiler said it was enough

They where very wrong

You could try removing all the grout and leave for a month or so
The groat will discolour and go patchy white anyway I'd think