screed depth for elec. UFH on timber suspended floor

[blu3tang]

Hopefully this in the right place.

Got the garage converted into a room last year.



Room has NO insulation under the floorboards.

So v cold in winter in the morning.

Floor is plywood with a gap under it of approx 160mm

Plan is to put insulation under floor board (approx 100mm) , and put electric UFH in.

1. What im trying find out is whats the ideal depth of screed required?
2. Use self levelling stuff?

Ideally wouldnt want it raised too much, perhaps no more than 20mm if possible from current location.

3. Am i asking too much?

4. I dont expect the electrc UFH to be on much, (insulation under the floor i expect will be a big difference.
Thanks in advance.
nick

 

[noseall]

You would typically lay a minimum of 75mm of sand/cement (un-bonded) screed above UFH.

Flow screed has its own niggles so not always suitable.

 

[blu3tang]

thanks for the quick reply.
the 75mm is that for electric under floor heating or just normal (wet) piped under floor heating?

 

[noseall]

Have i read your post correctly?

Are you saying that you are stripping back a floating timber floor in a converted garage back to the concrete and laying the inso' onto the concrete, with screed on top?

 

[blu3tang]

sorry no.

floating timber floor getting 100mm insulation underneath (as currently no insulation under the floorboards)

Then on top of the floating timber floor want to put electric under floor heating.

On top of the electric floor heating will be laminate flooring.

 

[noseall]

sorry no.

floating timber floor getting 100mm insulation underneath (as currently no insulation under the floorboards)

Then on top of the floating timber floor want to put electric under floor heating.

On top of the electric floor heating will be laminate flooring.

Why are you putting a floating timber floor back on top of the insulation, when you should be laying floor screed? I'm confused?
You can not mix the two.

A typical floor detail (complete) would be...
100-150mm compacted hard core.
Sand blinding layer.
1200g polythene.
100mm concrete floor slab.
100mm celotex.
Thin layer of polythene covering insulation.
UFH fitted to insulation.
75mm+ screed.
Decor layer, i.e. tiles, carpet etc.

I don't understand where your floating floor fits into any of this.