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hello
after a bit of advice really.
i'm wanting to put some underfloor heating into our house.
the floor i'm wanting to heat is currently bare concrete (it's part of a new extension we're having built) so i know i'll need to put down an insulation board, but how do i affix that to the concrete floor, (or can it be a floating type affair?)
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the above image suggest i need to affix it, but what with?!?! just normal flexible tile adhesive?
what kind of UFH, wet or electric?
Ideally you should have c.4" of polyurethane insulation (Thinsulate/Kingspan/Celotex) below your (3") screed within which wet UFH pipes are laid - the pipes can be pinned to the insulation or set into a grid matrix.
Presuming it's electric, tile adhesive would be best. Marmox make insulation board, with a cementitous backing on the top and bottom. They recommend using the same adhesive between the concrete base and insualtion board that you use to fix the tiled floor. Just have a look on the website of the insualtion board manufacturer that you go with.
Also depends on how pipe work fixed, if wet ufh. If it's in a cement based screed, this should be sufficient to hold down. If it's clipped in to foil sheets, maybe not. Depending on levels, if you have sufficient, the screed finish is much better dissipation of heat. You will be able to get fixings to hold insulation down, and don't forget to tape up any joints.
Stoner in not looking at the picture shocker 😉
I'd say he:
a) wants to use electric, and
b) doesn't want to rip up the floor and start again.
OP, I'd suggest finding out who makes the insulation board and checking with them. We've got EUFH in a bathroom but it's on a wooden floor so no insulation board.
top tips guys... and yeah, it's an electric system... thanks
Stoner in not looking at the picture shocker
I was subtly trying to point him in the RIGHT direction 😉
You can tell that subtlety was never my strong point 🙁