Insulate against underfloor heating?

[Jimman811]

Hello.

I need help with your knowledge and ideas.

I have a house where the living room is sunken (one step down). I'm so tired of this layout that I'm now considering raising the floor.

It is a cast concrete slab with underfloor heating, and the floor needs to be raised by about 30cm. I'm thinking I need to insulate it to prevent it from becoming a large resonating box, but do I then risk moisture problems?

Anything else I should consider?

//Jimmy

 

[Rabbithole]

Lay plastic on the concrete. Then just place the studs on the slab. Between the studs, lay a layer of insulation and that's enough. You don't need to fully insulate and thus avoid moisture problems.
Another option is to build up with foam plastic to the right level and cast a new slab.

I would suggest floor heating coils in grooved panels for the new floor and turning off the heat in the subfloor.

 

[Jimman811]

Thank you for the response. It definitely feels doable to finish the floor.

I don't know about the underfloor heating. Today it is waterborne, but it is throttled to the point that there is only circulation because we have a wood-burning stove in the room that is used quite frequently during chilly days, so we don't feel any direct need for the heat.

But when you suggest underfloor heating, are you thinking of electric?

//Jimmy

 

[Rabbithole]

No, waterborne, that you would then connect it to the existing system. But if underfloor heating isn't needed there, the project becomes considerably simpler. Laying out plastic, framing up, and laying floor chipboard goes quickly.

 

[Jimman811]

Waterborne feels like a big project.
Chisel up the existing slab to access the loop.
No, then I'll probably go with electric if heating becomes relevant.