Install On Concrete Floor

[simon]

I am fitting a new kitchen and want to also tile. As it is old its has a really cold concrete floor.

I have looked at all possible options for wet or elec UFH and insulation. Floating floor of 6mm hardi on 30mm celotex was almost tried until I read the forum some more. Wet UFH wont give me enough heat as its a 12.5m2 room and I can only get about 6-7m2 of UFH so really need 160Wm2 heating to supplement the radiator (currently there are two but im removing one)

So my plan is to simply lay 30mm marmox - Full bed adhesive it to the primed concrete floor (needs a bit of water based SLC in places to help avoid excessive adhesive), tape all joints with skrim, then lay down elec Matt (with supplement adhesive) then a 5-10mm layer of SLC before tiling with MAPEKER RAPID SET FLEX adhesive (300x600mm tiles) and polymer based mapei grout.

Have I missed anything, room is 2.5 x 5m. Any need for expansion gaps of the marmox?

Anything I should use for sticking the marmox to the floor.

Thanks all!

 

[J Sid]

before you rule wet ufh out have a talk to some like under floor heating store and they can design a wet system to suit your room size and available floor area.
done rooms with retro fit ufh of your size floor area, so may be possible

 

[Chalker]

Nu heat "Lo pro" will give 155w per m2

 

[simon]

Thanks, I have a max of 50mm to add before the floor it higher than the back door sill.

 

[Lee@emctiles]

Dont see any issues with the way you are doing the project, i'd consider a more simpler to instal ufh system however, there are 2 on the market, ditra heat and variopro, the guys using the variopro are saying they will never go back to using electric ufh mats again.

 

[Rich Midge]

I need to start looking at other ufh options. I've only ever used Warmup loose wire even on big floors without any issues whatsoever. Variopro and Ditra heat are absolutely alien to me! As for the op's install, sounds good to me. With regards to adhesives etc always go with the best your budget will allow. I almost always never use less than an S1 nowadays (Setaflex) even onto concrete with ceramics.

 

[simon]

Thanks. The variopro looks good. But more expensive than matts but I guess you save on SLC and it's quicker

Although the thinking about it you need double the adhesive

 

[simon]

Hi all,

Looking at the Warmup 200W/m 6m2 mat kit. Best price I found is £225. Loose wire is same price for only 1000W of heat. EZheat do a cheaper mat but seems warmup is well recommended here.

I did consider U heat mat but the cold return is only 4m and don't want to join it under the floor