Hoping someone can help with this query. We've recently had porcelain floor tiles laid in our new kitchen and extension on screed (some existing, some new).  The tiles have been down about 5 weeks. I'm aware that I should bring the floor temperature up gradually over a week or two and then reduce it gradually, to avoid thermal shock.

 

Is it OK to do this by heating the relevant zones for shortish periods (say a couple of hours at a time) at normal flow temperature (about 40c) followed by turning the zones off to allow the screed and tiles to cool down, as opposed to turning the c/h boiler down to 30c and then moving up in increments? I'm keen to avoid the latter because the rest of the house will be uncomfortably cold. My thinking is that if it's only on for a short period the floor temperature won't get high too quickly.

 

Would appreciate any thoughts on the matter.  Thanks.

If it’s been down five weeks You can put the heating on as normal without damaging the tiles