Residual moisture in new build floor - TilersForums.com

[Stu Brard]

Hello guys, I am in need of some advice. I’ve started tiling the entire downstairs of a new build property (Bovis).

I’ve used Dural durabase as a decoupler and started tiling. I noticed the next day that the adhesive wasn’t drying fully and looked damp in places. I lifted a tile and the addy hadn’t fully cured underneath.

I left a bucket on the floor and there was a damp ring formed under there also. My thoughts were that there must be some moisture still in the floor? Some guy from Bovis has been round and said it’s fine but I’m not convinced.

the subfloor is 75mm Fibrecrete and the roof didn’t go on until October. Is there a reliable way of checking whether the floor is dried out enough?

Any help very much appreciated

 

[J Sid]

The adhesive between the uncoupling and tile is damp?
What adhesive have you used?
Slow set will not fully cure for weeks and rapid can look damp for days depending on the temperature.
A damp screed will be fine with a cavity mat like ditra and not affect what's above it

 

[Stu Brard]

The adhesive between the uncoupling and tile is damp?
What adhesive have you used?
Slow set will not fully cure for weeks and rapid can look damp for days depending on the temperature.
A damp screed will be fine with a cavity mat like ditra and not affect what's above it

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Hi Julian, I’m using rapid set (Topp’s tiles own brand). Yes it’s between the tiles and mat where I’ve noticed the moisture. That being said I’ve not yet lifted the durabase to have a look. I’m a bit stuck with how to proceed as my gut feeling is the floor hasn’t had enough time to dry out. Now I’ve capped it off with a decoupler and tiles it’s like the floor is beginning to sweat.

 

[Dumbo]

Hello guys, I am in need of some advice. I’ve started tiling the entire downstairs of a new build property (Bovis).

I’ve used Dural durabase as a decoupler and started tiling. I noticed the next day that the adhesive wasn’t drying fully and looked damp in places. I lifted a tile and the addy hadn’t fully cured underneath.

I left a bucket on the floor and there hygrometer

[automerge]1579117426[/automerge]
Hi Julian, I’m using rapid set (Topp’s tiles own brand). Yes it’s between the tiles and mat where I’ve noticed the moisture. That being said I’ve not yet lifted the durabase to have a look. I’m a bit stuck with how to proceed as my gut feeling is the floor hasn’t had enough time to dry out. Now I’ve capped it off with a decoupler and tiles it’s like the floor is beginning to sweat.

The floir can breath through the cavity air channels that why Schluter say and I think dural also they are happy for the mat to go on the screed as soon as it is dry enough to be weight bearing , which is wet

 

[Ajax123]

moisture between the tiles and the mat is nothing to do with the screed/concrete underneath the mat. the presence of moisture in the screed/concrete wont prevent the adhesive from setting. It might stop it sticking but wont stop it setting. the only time ive seen what you are describing is where tubbed adhesive was used... not saying you've used tubbed but thats is the only time ive seen it.