On 21/05/2019 23:05, Steve Walker wrote:
On 21/05/2019 21:46, Roger Mills wrote:
On 20/05/2019 16:38, R D S wrote:
I want to overboard a draughty, uneven floor.

And as I could do with raising it about an inch I was thinking about a
thick insulation inbetween.

Then I started thinking about UFH and there are pre-grooved polystyrene
panels that would be ideal.

So just wondering if anyone has any experience of DIY UFH or any
opinions of UFH in general.

If you can only raise the level by 1", your options are very limited.
There's nowhere near enough room for a wet system, so it would have to
be electrical - which would be very expensive to run. Even then,
there's insufficient headroom for a decent amount of insulation.

When we converted an integral garage into a kitchen, we needed to
raise the floor level by 6". We installed a wet system but even 6" was
tight and only allowed for about 3" of insulation in order to make
space for a couple of inches of screed on top of the pipes.

You don't have to use screed. There are systems that use thin, grooved
insulation on top of the existing floor, with the pipes in it and metal
spreader plates to spread the heat. With a few mm of laminate floor
underlay on top and then laminate. 1" might be more than a bit tight
though. Further insulation can be put between the floor joists.


And then you have to alter the stairs.


--
Adam