UFH and hardiback

[waterfd]

I will be doing a floor in the very near future and when I checked the customer had installed wet UFH under the chipboard floor. I was going to use Ditra but if I do then no heat will get to the tile. I've checked here and 6mm hardibacker sems to be the next prefered method. Would using flexi adhesive be necessary under the board. I will also have to be careful not to screw into the heating system. Any advise please.

 

[wetdec]

Hi

Using an uncoupling membrane will not stop heat getting through if anything because of the structure of Durabase Ci for eg the air pockets help retain the heat for longer. Using a substrate board will hold the heat down m8


cheers

tiler


..

 

[DHTiling]

Your best option is the uncoupling membrane....this will cope with the lateral expansion from the ufh...hardi backer won't........and it sticks down with adhesive , so no risk of hitting the ufh with screws...

give wetdecs a call and he will sort you a good deal out on the uncoupling membrane...

 

[Grace'sDad]

Hardibacker is a good insulator and will really keep the heat underneath - not a good idea!

 

[grumpygrouter]

I will be doing a floor in the very near future and when I checked the customer had installed wet UFH under the chipboard floor. I was going to use Ditra but if I do then no heat will get to the tile. I've checked here and 6mm hardibacker sems to be the next prefered method. Would using flexi adhesive be necessary under the board. I will also have to be careful not to screw into the heating system. Any advise please.

I assume the chipboard floor is solid enough to be able to use ditra without additional strengthening?

 

[waterfd]

The floor is well fitted with no deflections in fact the guy who fitted it used a lot of screws. From what you have all said Ditra is the way to go thanks, I prefer this option since I will not have to worry about screws. Will be starting this on Friday.
Rgds Des.

 

[grumpygrouter]

The floor is well fitted with no deflections in fact the guy who fitted it used a lot of screws. From what you have all said Ditra is the way to go thanks, I prefer this option since I will not have to worry about screws. Will be starting this on Friday.
Rgds Des.

Just please bear in mind that Ditra/Durabase only isolates from lateral movement, it will not absorb deflection so there is still potential for tiles to crack if the floor deflects!