Underfloor heating insulation

[skinnymalinky]

Howdy Hoping for some thoughts on this...

I am keen to install underfloor heating in my (upstairs) bathroom and looking at Warmup's electric system as a fairly cheap and simple option. However, they recommend cement insulation boards as part of the system to improve the efficiency. Clearly not a "breathable" material! So I just wonder what people think about that - or does anyone have their own experience with this?

I will have some Thermafleece slabs left over that I could potentially stuff under the floor if I lift the floorboards instead but I wouldn't know how effective or otherwise sensible an idea this would be. Any thoughts?

Thanks for any input as always!

 

[fernicarry]

The cement boards are more to act as thermal mass, like an old fashioned storage heater, not for insulation value so you'll need the boards and also to insulate below. I put 80mm of wood fibre insulation between my joists. Your thermafleece could be used but make sure its well supported so that it stays in contact with the underside of the floor. I used the same wood fibre in the studwork on the external wall.

If the floor is tiled its not going to breathe anyway so I wouldn't worry too much about that. Do make sure you have an effective extractor fan to remove wet air after use.