Underfloor heating - right adhesives?

[newbieneedshelp]

Hi guys, im trying to understand the installation of my underfloor heating kit, its various 'levels' of construction and the correct adhesive reqired at each level.

The concrete sub floor has now been levelled and is ready for installation.

The 10mm therm-a-mat insulation panels and the warm up kit arrived yesterday so Im now trying to get my head around the whole project properly.

Im assuming the following:

10mm insulation down first - adhered to the concrete sub floor with a quick drying water based adhesive - is this correct and if so does the type have to be any more specific?

Then the matting is put in place above this - do I need to use the same adhesive here also?

Then, as I understand it, the tiles are placed directly on the matting - again - does this need to be the same adhesive as mentioned above?

And finally, just a normal grout for a UFH tile installation?

You can gather that this is all new to me! Any help would be great,

Thanks,

Lee

 

[bathstyle]

You have a few choices of adhesive to glue the board down. I would go for Toppfix rapidset flexible grey, it's £10 for a 20KG bag, once set, go over the boards joints with manufacturer specific glass fibre tape, trowel over it with more of the above adhesive.

Then fix your UFH Matt. Follow the warmup installation procedure, it's fairly simple to understand.

Then you can either level over the floor with a self leveller suitable for UFH such as Arditex two part levelling compound or float the floor with Tile adhesive, (Toppfix)

Once set, tile in the normal way, again, use the Toppfix.

Toppfix rapidset flexible grey or white can be bought from Topps, it's half the price of Bal Rapidset flexible grey I believe and has virtually the same spec as it.

Grout, go for Bal Superflex wide joint.

 

[newbieneedshelp]

Thank you very much for the reply. Thats answers my query perfectly.

 

[bathstyle]

Oh yeah, don't switch the UFH on for a month after the whole floor has been tiled and grouted, the adhesive normally sets in 3 hours, enough for you to stand on the floor but takes a lot longer to fully cure. Heating the adhesive too early can cause the adhesive to cure too quickly and give you problems.

Test the UFH at every stage of the process too, use a multimeter

 

[newbieneedshelp]

Hmmm, slight timing issue on this one as the guy (who wasnt picking up the adhesive until Monday) turned up this morning with it!!

Can anyone confirm if this is suitable: (it does say its 'compatible' with underfloor heating systems on the packaging)...

He's obvously keen to get going on Monday so I need to discuss this with him if its really isnt the right stuff to use.

Thanks in advance,

Lee

 

[bathstyle]

Never used it so cant comment, looks good though, same spec as bal rapidset flexy and Toppfix I imagine

 

[tictic]

might be a bit late here op
but when using ufh..matt,cable...i always put a latex over it using plastic trowel as not to damage any of the ufh, again as bathstyle said check ever m2 with multimeter