Screed \ Under floor heating advice - TilersForums.com

[ajkzrr]

Hi,

We have had a screed (anyhdrite) with wet underfloor heating put down recently. After a few weeks they turned on the heating and then after a few days a small dark spot appeared, this grew in size to a 10cm elongated circle. There is metal pipe coupling directly below.

We suspected a leak.

Anyway, we had the contractor back today, and he said it was n't a leak as it would be a circular shape if leaking.

That does n't sound right to us. Does anyone have an experience of this? What else could explain it?

Thanks,

 

[Dan]

How many weeks? And was the heating commissioned correctly?

You have to bring it up to temperature slowly, then leave it on full 24 hours, then bring it back down a degree or two per day to cold. Then it can be used as you wish.

Without doing that process you stress the system and the floor.

You have a leak for sure. That's wet right? Did the contactor pressure test it?

 

[ajkzrr]

How many weeks? And was the heating commissioned correctly?

You have to bring it up to temperature slowly, then leave it on full 24 hours, then bring it back down a degree or two per day to cold. Then it can be used as you wish.

Without doing that process you stress the system and the floor.

You have a leak for sure. That's wet right? Did the contactor pressure test it?

[automerge]1575315567[/automerge]
Screed was down for 3 or 4 weeks before the heating was turned on. Heating was turned up to 40oC was commissioned, and has not been brought back down..

Yes, look wet to me too.

Pipes and screed were put down in one day, so not a long pressure test if any.

 

[Dumbo]

Looks like a leak , ask him if it's not a leak can he explain what it is

 

[Dave]

Its not common practice to put a joint in the pipes within the screed.

 

[Ajax123]

I would have said leak as well. Although its very well defined. I might look at potential surface spills eg grease, oil etc...Is it continuing to spread?

 

[Uheat - Jake]

Looks like a leak from the joint below. UFH should be one continuous run of pipe from the manifold and back with no joints.

 

[Dumbo]

It's fair enough to say that pipes should be continuous with no joins, of course they should , but if the pipe got damaged at some point it would be necessary to repair it .

 

[Ajax123]

There are proprietary joints for UFH pipes but the preference is always jointless. This doesnt look like a leaking pipe though. it is too concentrated. In a screed the water would spread much more especially in anhydrite. Unless the pipe is very close to the surface.... I think it needs further investigation. Does the dark patch feel wet to the touch?

 

[J Sid]

Has anyone looked up?

 

[ajkzrr]

Thanks All.

The patch is expanding slowly now. There has been no rain and there are not any pipes above it.

When the contractor came he said that the coupling was quite close to the surface.

 

[Ajax123]

Thanks All.

The patch is expanding slowly now. There has been no rain and there are not any pipes above it.

When the contractor came he said that the coupling was quite close to the surface.

Ah well if it is indeed expanding slowly leak it probably is... it needs excavating and affixing properly then. Was the system not pressure tested properly before screeding?