Suspended floor insulation for UFH

[robinbanks]

Proper? I agree to do away with the joists, 200mm of king span seconds on the slab (cheap as and wibblywobbly as you like), clip the UFH pipes to it then pour a liquid screed over the top. Isolate your screed from your walls with more insulation

 

[riddellns]

Proper? I agree to do away with the joists, 200mm of king span seconds on the slab (cheap as and wibblywobbly as you like), clip the UFH pipes to it then pour a liquid screed over the top. Isolate your screed from your walls with more insulation

I can't tell if it's actually that simple or you're joking?!

Obviously there needs to be a DPM below the insulation, but I guess that works.

What happens with the air bricks etc?

 

[robinbanks]

You can put a DPM below if you like, but kingspan doesn't readily take on moisture. There will be a DPM below the screed to stop it flowing between the insulation sheets

The joists will be gone; no need for air bricks because your ground floor is now composed of materials that do not need airflow. Do away with them and enjoy elimination of another major cause of paid-for-heat loss

 

[riddellns]

Is it sensible to lay a thin layer of sand over the blinding to make sure the PIR sits flat?

The current joists are built off a sleeper wall built off the blinding slab, so the slab is already taking the full weight off the flooring and foot traffic etc. So surely this is an obvious solution!
Or are building control just going to rip this plan apart?

 

[robinbanks]

Is it sensible to lay a thin layer of sand over the blinding to make sure the PIR sits flat?

Doesn't matter a carrot if you're installing liquid self levelling screed, unless you're saying that the whole slab slopes appreciably

If you said to your BCO that you were going to install more insulation than the bare minimum regs allow and a heated slab, I'm sure they'd be overjoyed

 

[cdbe]

Might be worth checking with BC first. My oversite is crap - just a smear in some places, and the sleeper walls are built off it - I hope it's a bit thicker under them. Just in case they want it breaking out and the standard 100mm of compacted MOT going in.

 

[riddellns]

Might be worth checking with BC first. My oversite is crap - just a smear in some places, and the sleeper walls are built off it - I hope it's a bit thicker under them. Just in case they want it breaking out and the standard 100mm of compacted MOT going in.

yeah fair. I just know that if I didn't they'd definitely ask me to prove it's fine
Appreciate the info guys, thank you