Wunda - Tile Advice

[Etherglide]

Hi guys. Client is installing Wunda underfloor heating on the first floor. Ive never done it before so Im looking for some advice. Wunda tech team has given us three options. Tile straight on top of the polystyrene and integrate the ahesive into the exposed pipework. Lay Ditra over the top and then tile. Or lay interlocking hardiebacker board and then lay on that. Problem is the Hardiebacker board is 18 mm thick. The tech tean has also said the we must use the mapei s2 adhesive but my local store can only supply the keraquick with the lstex additive and that works out quite expensive. Any help would greatly appreciated.

 

[Cherie]

How big are your tiles?

 

[Cherie]

Big tiles, ditra, hands down.

 

[Cherie]

Found an old thread

https://www.tilersforums.com/threads/tiling-failure-over-wundafloor.85516/tags

 

[Kevbos]

Hi guys. Client is installing Wunda underfloor heating on the first floor. Ive never done it before so Im looking for some advice. Wunda tech team has given us three options. Tile straight on top of the polystyrene and integrate the ahesive into the exposed pipework. Lay Ditra over the top and then tile. Or lay interlocking hardiebacker board and then lay on that. Problem is the Hardiebacker board is 18 mm thick. The tech tean has also said the we must use the mapei s2 adhesive but my local store can only supply the keraquick with the lstex additive and that works out quite expensive. Any help would greatly appreciated.

I listened to Wanda and mapping tech guys on an installation of 1200x1200 6mm porcelain onto of wundas foil backed underfloor heating boards !! It did not work , it failed , the tiles all cracked , and I was very glad I made this my opinion before using the system .I do find it funny being told some things will work , like they have tested it for 15 20 30 years

 

[Etherglide]

Thanks to all. We've gone with the 18mm Hardiebacker option. Its a floating floor with no fixing and Ive used the Mapei S2 adhesive. Until the heating is turned on we won't know but I have covered myself.