ᐅ Insulation / Underfloor Heating in a Partially Basemented House

We have bought a house with a partially finished basement. Now the question is how to best approach the insulation and installation of the underfloor heating.

In the basement area, there is no problem. Insulate the basement ceiling, then install the underfloor heating either as a dry system or recessed into the floor.

How can this be done in the non-basement areas? Remove the screed, then insulate, then install the underfloor heating, followed by another layer of screed? Or is there underfloor heating with built-in insulation underneath?

Does anyone have experience with this?

Daniel86 schrieb:

No problem in the basement area. Insulate the basement ceiling, install underfloor heating either as a dry system or by chasing into the screed.

Or remove the screed and redo it properly. This way, you can also choose smaller pipe spacing (5cm (2 inches) is generally not possible with chasing) and insulate beneath the screed, so the basement ceiling does not need as much insulation (which saves headroom in the basement).

Daniel86 schrieb:

How does this work in an area without a basement? Remove the screed, then insulate, then underfloor heating, then screed again? Or are there underfloor heating systems with built-in insulation underneath?

Sure, as long as the heights allow it – remove the screed, insulate, install underfloor heating, then screed again. And because this is the standard procedure, there isn’t a special product called “underfloor heating with built-in insulation” – did you imagine something specific underneath?
If the heights are insufficient, it just becomes less efficient and/or pipe spacing needs to be tighter.

If possible, when renovating, I would always remove the old (floating) screed (you can do this with a heavy hammer on a Saturday with friends even for the whole house). Rebuilding is not more expensive but offers much more flexibility (including the possibility to lay electrical conduits on the raw floor).

jens.knoedel schrieb:

"Underfloor heating with built-in insulation" – did you have something special in mind underneath?

There are at least these studded panels for installing underfloor heating, which come with 3cm (1¼ inches) impact sound insulation below... Rolljet or foldable panels are also available (with stapling grid for underfloor heating) – but that's only sufficient as the top layer. For floor insulation between the rooms and the basement, there should be more insulation underneath.

-LotteS- schrieb:

There are at least these studded panels for installing underfloor heating, which come with 3cm (1.2 inches) impact sound insulation underneath.

That is the overpriced option for all lazy builders. Usually combined with the worst possible insulation (thermal conductivity class 35-40) and limited flexibility in pipe spacing.
PUR insulation boards and grid foil. But then you have to staple and carefully plan the installation – the studded panel makes life easier and, of course, eliminates the need for thorough installation planning.

jens.knoedel schrieb:

This is the overpriced option for all lazy craftsmen. Usually combined with the worst possible insulation (thermal conductivity 35-40) and limited flexibility in laying distances.
PUR insulation and grid foil. But then you have to staple it and figure out how to lay everything – the studded panel makes life easier and, of course, eliminates the need for precise installation planning.

For our KfW40 new build on the ground floor (no basement), we used 12cm 035 (10 inches, thermal conductivity 0.035) and 2cm Puren (I think it’s even 023), then a grid foil, and we staple the underfloor heating on top. Upstairs we used 8cm 035 and 2cm staple-folded panels (I believe those were also 035, but upstairs that doesn’t really matter). I can look up the exact figures if desired (prices Dec 23/Jan 24 Lower Saxony)...

But the question was whether something like this exists.