Tiling and underfloor heating help - TilersForums.com

[Mark wemyss]

evening

Laid isoscreed/anhydrite at 65mm on the 21/3/17 Ina new build property over underfloor pipes laid into inserts

Screed has since been sanded ready to receive the floor tiles.

Question is do I need to switch the ufh on? And if I do for how long (a day or a week etc)

Sorry for the newbie question but heard different reports where the ufh needs to be on for 2 weeks and off for 2 and others not on at all and just simply install the tiles

Any help welcome

Many thanks

 

[Flintstone]

I stand to be corrected on the exact times but I think it's switch it on low and work it up By maximum of 5 degrees per day until you reach a high temp. then run it for a week at high temp. Then reduce it over a few days and switch it off 48 hours before tiling

 

[Flintstone]

Have you moisture tested this screed as It won't be dry enough for tiling I'm sure.

 

[Mark wemyss]

Hygrometer will be going on it tommorow to double check.
If it is within the limit am I good to tile or does the ufh need to be switched on

 

[Flintstone]

You must switch it on in the manner I've said above

 

[Uheat - Jake]

As the system is used for first time, the mixing valve must be set to minimum setting to let the moisture in the screed to dry out. The temperature should be increased by 2 degrees every day until the mixing valve is set at 45°C (about 5 days).

Once the mixing valve is set to:

45°C for Screed Floor
55°C for Timber Suspended Floor with Aluminum Spreader Plates

set the room thermostats to required levels and programme the system controls to run as required.

 

[Chalker]

You will be amazed how much moisture will come out of the screed once the ufh is turned on.
As above, it needs commissioning before tiling