Overlay Underfloor Heating

[ah666]

Hi,

Looking for some advice with respect to installing underfloor heating and tiled floor into a kitchen 30m2

• The current floor is concrete and not screed (we know this to our expense when we had to lay new pipework for central heating and channel out pipe runs)
• I have a quote from a heating engineer to install UFH (wet system) which involves taking up around 100mm of the concrete fitting insulation then UFH and topped with Brio board, and tiling straight onto Brio board. However this quite was very expensive and frankly I couldn’t justify the outlay
• The heating engineer has subsequently come back with an overlay system (I believe from Polypipe) that would sit on top of the existing concrete floor and is only 18mm thick to which I could tile directly onto, thus the UFH pipes would have direct contact with the tile adhesive
• Thus although not the ultimate solution its around half the cost and would only give us around a 30mm step

Does anybody have any experience with this type of system ? and if so any tips for when I tile the floor, I am fairly competent DIY tiller (see photos of my last project in my previous posts, hopefully this link works )http://www.tilersforums.com/tiling-forum/69763-finished-ensuite.html#post708309 but this is making me nervous

Thanks
AH666

 

[One Day]

Schluter Bekotec therm would be a better system for many reasons.
Main one is it is designed for tiles and stone.
Polyplumb appears to be have been designed to RUIN tile and stone - or at least make life difficult for fixers.

Underfloor Heating System - Schlüter-BEKOTEC-THERM - Schlüter Systems

 

[andyb1]

Only 18mm thick! Going to use a lot of adhesive / latex then,

 

[widler]

Ive tiled over it, was nice and the bloke loves it, still does , no problems 12 months (nearly) later, and its blinking boiling

 

[One Day]

Ive tiled over it, was nice and the bloke loves it, still does , no problems 12 months (nearly) later, and its blinking boiling

How did you tackle it?

 

[widler]

I put a thin coat of addy over everything , let it set then just tiled it as normal

 

[ah666]

Hi Wilder how did you deal with commissioning the system ? did you turn on the UFH after applying a layer of addy or wait until the tiles had been put down ?

 

[young1066]

hi,i have tiled over this system before,but its better and easier to pore self levelling latex over it first till its covered,latex will expand and contract with the heating and is also used on electric heating,use less flexi adhesive,and makes it easier to tile, I use ultra self levelling from topps tiles clearance

 

[widler]

Hi Wilder how did you deal with commissioning the system ? did you turn on the UFH after applying a layer of addy or wait until the tiles had been put down ?

It was pressurised before tiling but not turned on until a few weeks after,starting low and turning up every day or so .
Imo slc aint need,as its only put over electric UFH so you don't really damage the cable. The floors are flat as a pancake(ish 🙂 ) i just skimmed it to fill the odd hole.
Here you go a couple of pics ive found, as you can see not much skimming of addy as been done at all

 

[Old Mod]

I tiled one like this middle of last yr. The heating guys overlaid with 6mm ply and contractor laid Ditra. I just tiled it. 8 months on and not heard anything detrimental about it. First one I'd done. I'm in contact with contractor on regular basis so I know he'd say something if there was a problem.