Will it melt the ditra?

[Brad]

hi all.........

i know the correct procedure is ufh under ditra matting, but there are tilers out there who prefer installing the other way round, ufh over ditra. Would there not be a risk of the ufh melting the ditra. lets say the control box or probe is faulty or hasn't been installed properly......what would prevent the matt from overheating and melting itself into the ditra? After all, some systems can get rather hot. The devi mat system can apparently reach 50 degrees! Replies appreciated....

 

[Ian]

Put the heat mat down, encase it in SLC and then fit the ditra, this way the ditra isn't in contact with the heat wire.

 

[Brad]

Put the heat mat down, encase it in SLC and then fit the ditra, this way the ditra isn't in contact with the heat wire.

Thanks Bri.......I know the correct procedure.I was asking about the safety risks of installing the other way round.....

 

[Stewart]

It would depend on the wattage of the mat and making sure the mat was encased fully in slc. I have done it with a 100 watt mat on top of Ditra as a retro fit, but was given the all clear from Schluter and Heat Mat........

 

[Ian]

Here's an extract from the schluter web site

Radiant heated screeds
Schlüter-DITRA may be used over heated screeds as described in the sections on mortar screeds and gypsum based screeds. With Schlüter-DITRA, tiles can be heated seven days subsequent to installation. Starting at 77 ºF (25 ºC), the radiant heated floor temperature can be raised gradually by +9 °F (+5 °C) per day, to a maximum of 104 ºF (40 ºC). The air channels of Schlüter-DITRA allow for a quick and even distribution of heat below the tile covering.
Note:
For radiant heated floors, we especially recommend our system Schlüter-BEKOTEC-THERM, the ceramic thermal comfort floor. Schlüter-DITRA is also recommended for uncoupling of radiant heated floors consisting of thin electric heating mats. Schlüter-DITRA may be installed either above or below the heating mat. However, the uncoupling function is more effective if Schlüter-DITRA is installed above the heating mat.

Doesn't really give a definitive answer to your question, but does say it is possible to do it. I think the 40 degrees high temp is a key point.

 

[Ajax123]

PVC which i beleve is what ditra is made from has a melting point of around 175degrees c. I dont tink ufh is going to cause much of an issue

 

[Diamond Pool Finishers]

as above i have installed it as follow ditra,heating elements, glue -gunned down, SLC ,then adhesive , tiles, and had no probs.......

 

[Russ clark]

Put the heat mat down, encase it in SLC and then fit the ditra, this way the ditra isn't in contact with the heat wire.