ᐅ How to Construct the Floor? Electric Underfloor Heating with Insulation

Hello everyone,

we have decided on a new kitchen. Before it is delivered, I will renew the electrical installation and the flooring.
Below our kitchen is an unheated basement room. So far, we have noticed this clearly, as we often had cold feet. Our house was built in 1954.

My idea now is, while renewing the floor, to install underfloor heating at the same time. Due to the “small square meters” and limited installation height, I would choose an electric underfloor heating system from AEG, for example, the TBS TB50 Thermo-Floor.

My question:
What would a proper floor build-up look like?

Currently, the old floor is still installed. There are two layers of tiles on top of each other, as I have already seen. We don’t have a wooden floor but a kind of concrete beam structure (like concrete slabs with hollow spaces) with reinforcing steel. I don’t know the exact term for it.

My understanding:
If the tiles are completely removed, an insulation layer should be installed first. Is that correct? I would prefer a dry construction method.
The electric heating would be installed on top of the insulation, followed by the new tiles. Is that correct?
Important: The floor build-up must, of course, be able to support the kitchen.

Do you have any tips for the proper build-up? Can you also recommend suitable products?

Thank you very much for your help.

Hello Builder,
of course, everything is very speculative. You probably have a ceiling made of lightweight hollow-core slabs, with double T beams every 60cm (24 inches) and concrete elements in between.
Demolish everything up to that point. Insulation: I am a fan of Linitherm or similar, 60mm (2.4 inches) depending on what is possible, separating layer, underfloor heating, thin screed.
But please, to the critics: diagnosis from a distance without exact knowledge, feel free to send a private message.

When installing underfloor heating in an older building, it is important to fit as much insulation as possible into the limited space available. As already suggested, remove the old flooring. Then, I would consider using XPS construction boards (such as Wedi, Jacko, etc.) and check if they can support the weight of the kitchen. It should work. This way, you won’t need an additional screed layer, and you can either tile directly or install the underfloor heating in between. Alternatively or additionally, you should also insulate the basement ceiling (in all rooms), provided the ceiling height in the basement allows it.