Water UFH - Is this possible?

[jimmycooker]

Hi,

I have poured my concrete floor (100mm) on top of 100mm of kingspan insulation.

I have just under 40mm to play with to fit underfloor heating and tiles to bring it up to finished floor level.

I was planning on fitting the insulated 25mm www.floorheater.co.uk panels with tiling on top.

What i want to know is would it be possible to just lay 20 - 25mm barrier piping on top of the concrete slap and pour a screed over the piping and then tile on top?

My main reason for doing this is the cost of the floor panels, i'm not too worried about the heat up time or costs, the intial outlay is my main concern.

Another idea i had was to just buy plain EPS panels, cut my own channels into them and tile on top of them. I think the floorheater are jablite...anyone have any ideas?

Thanks,
James.

[garythetiler]

i think you will find you need a 60mm screed on top of piped ufh unless you go gyvlon where it is still recommended 40mm i believe ,you will still need to stick you tiles down too which will be a minimum of 13mm depending on the material so I am guessing you dont have enough depth at 40mm all in

[jimmycooker]

So you don;t think there's a screed I could pour to a depth of just 25mm?

[garythetiler]

just looked at the link these panels do look great and if the marketing info is correct then 40 mm should fine

[garythetiler]

So you don;t think there's a screed I could pour to a depth of just 25mm?

i cant see the adhesive companies guaranteeing their products on such a thin unbonded screed

[jimmycooker]

even when pouring onto a 100mm concrete base? What about the EPS boards, would you be familiar with them / the material?

[Ajax123]

Yes this is absolutely possible but probably not using 20mm pipes.

The cheapest I guess would be to use a calcium sulphate based screed. Lay a DPM grade polythene membrane onto the concrete then attach 10mm underfloor heating pipes to the polythene using self adhesive clip rails or even decent quality duct tape. Then pour 40mm nominal depth of anhydrite screed onto the lot.

You could also investigate the Max4 Therm underfloor heating system which allows an even thinner screed (20mm) which would then allow you to put a 20mm layer of insulation down on top of the concrete in order to help improve the efficiency of the system. It would also need a Flowing screed.

Schluter do a system called Bekotech Therm which I think might be able to go to this sort of depth as well. This need minimum 8mm cover to the pipes which would need to be a C25 - F4 flowing screed.

There are probably other systems as well.

[garythetiler]

Yes this is absolutely possible but probably not using 20mm pipes.

The cheapest I guess would be to use a calcium sulphate based screed. Lay a DPM grade polythene membrane onto the concrete then attach 10mm underfloor heating pipes to the polythene using self adhesive clip rails or even decent quality duct tape. Then pour 40mm nominal depth of anhydrite screed onto the lot.

You could also investigate the Max4 Therm underfloor heating system which allows an even thinner screed (20mm) which would then allow you to put a 20mm layer of insulation down on top of the concrete in order to help improve the efficiency of the system. It would also need a Flowing screed.

Schluter do a system called Bekotech Therm which I think might be able to go to this sort of depth as well. This need minimum 8mm cover to the pipes which would need to be a C25 - F4 flowing screed.

There are probably other systems as well.

he has less than 40mm all in, including the tile and adhesive ,the panels in the link allow the use of an s2 adhesive straight over the ufh so i would advise to bite the bullet and pay out for these if they are guarateed

[Ajax123]

Sorry - I misread the post. The Max4 Therm system would still be a realistic option and just as guaranteed. So looks like 2 options.

I prefer the idea of putting an insulation board down on top of the concrete thoguh as this will prevent the concrete from acting like a thermal sink and allow greaer efficiency of the heating system.