Tiling and UFH

HobNob

Hi All,

just wondering if underfloor heating has to be on before tiling.
we have gone with geothermal with UFH and now I'd like to start tiling, but
we have not got our heat pump installed yet. can I go ahead and
tile my floors and walls ?

any advice appreciated

mr_edge_to_you

We're about 3 months ahead of you. You need the heating about 4 weeks before you start tiling. The floors will expand and contract and destroy your tiles will be destroyed. You need to allow the house to cool down before you start tiling. That'll take a week.

HobNob

thanks for the info Mr_Edge,

was hoping it wouldn't take that long, was planning on two weeks
just especially since the days have been warm for the last few weeks.

3 months ahead of me. Have you moved in ?
I hope to be in 3 months time

tails_naf

I'd heard info like this before - perhaps someone can clear up the order of heat on/off, and in general how things should be done.

For example, heat should be off when plastering (plasterer said it needs to dry out naturally or will crack)

According to this thread, the underfloor needs 4 weeks to 'cure' - is this always the case? My concrete slab has been down 8 months, but even though i have not turned on my UFH yet, do I still need to do the 4 week cycle of increasing the temp gradually and then letting it cool down before doing any flooring?

What about laying wood flooring - any special heat/cool rules here?

soldsold

I was told last week by a gypsum rep with 25 years plastering experience that using a couple of basic office fans with the windows open will make a huge difference to drying out time, without the potential cracking issues of having heating on to dry out the house. His advice was that the fans made the natural drying more efficient, without the risk of cracking

Quack13

Was speaking to my architect about this as we hoped to have heating on in the next week or so, and tiler starting in 2-3 weeks.

I mentioned to him about thread on here, saying to have the heating on for 4 weeks before tiling.

His response:

'The tiles won’t go anywhere but it’s the screed that could break up. The rule of thumb is to bring the heating up slowly , then when it’s at max to leave it like that for 48 hours. Then after the 48 hours to reduce it slowly over 48 hours back to nothing.

I can understand the logic of this if you were doing the work in Winter and you planned to move in 2-3 weeks later and the heating will be on full time but in your case its summer. You’ll test the heating to see if it works but then it will be off until October – November and even then it will only be ticking over until the really cold weather December – February'

mr_edge_to_you

48 hours! Find that hard to beleive. It took our house a week to cool down! Our tiling cost 8k. Only intend doing it once.

mr_edge_to_you

The difference you will see in the concrete slab when the heating goes on is enormous. Just watch the areas where you don't have ufh such as kitchen units. It says it all! You'll be quite surprised.

stephendevlin

I work in a tile shop. best advice I can give you is leave it at least 6 weeks. or as long as possible. time costs you nothing! however pulling up floors and trying to replace tiles ....

this will give you plenty of time for the underfloor heating to show you any installation issues. but the floor needs to be as dry as possible before tiling starts.