Underfloor heating in old buildings, subsequent installation

I am surprised that as a veteran you have a problem with someone wanting to gather opinions and information in a forum.

I'll report on our old building renovation. Underfloor heating was also a top topic... We don't have high ceilings, so we didn't want to add height. We decided on a water-based underfloor heating system, which is fed by the return flow of the regular radiators. These heating coils are laid directly under the tiles, so there is no loss of height. It has worked perfectly for 12 years, and although it only provides heating, we don't use any other heat sources for these rooms (even though they are available). In addition to this water-based system, these thin-bed heating systems also exist in electric form. But if you really renovate, meaning tearing down walls, moving them, etc., you should consider raising the door lintel and removing the screed to install a proper underfloor heating system.

Others have already answered in detail.

Yes, it works. And yes, it generally works quite well. Even in old buildings - but not if they are energetically also still old buildings. At a minimum, modern (and thus probably new) windows, insulated basement ceiling and insulated top floor ceiling (or roof) should be in place for it to work well. In addition, a design that allows for the lowest possible supply temperatures = absolutely no never nowhere more than 10cm spacing, rather 5 - 7.5cm spacing. Then it also becomes economical to heat with electricity.

I am surprised that you, as a veteran, have a problem with someone wanting to gather opinions and information in a forum.

Whoever you may mean by "veteran" (I haven’t encountered anyone here yet), as far as I know, no one here objects to an interest in information. However, information does not make an exception to two nasty phenomena: namely that the dose makes the poison, and that even for something good/right there can be a wrong time. Furthermore – as I already pointed out – every real used property has somewhere not quite a hundred points, and one then has to decide which criterion he is least willing to compromise on from his wish. At this point I try(ed) to stimulate some reflection on whether underfloor heating or its easy retrofitting would be a good master question – as a killer criterion I would recommend it even less. So: before gorging yourself on information, first sort by (personal) importance which you want to use. In a free country, this may well also be something I would classify as least important.

Thank you very much for your answers. The topic of underfloor heating is important to us, and when it comes to renewing the heating system, I find a heat pump combined with underfloor heating very good. I did not know that it is much easier than I thought.

I assume that the biggest costs are the removal of the gas heating system, the installation of the underfloor heating, and the implementation of the heat pump (since the pipe to the heat pump has to be laid afterwards).

I assume that the biggest costs are the expansion of the gas heating, the installation of the underfloor heating, and the implementation of the heat pump (since the pipe to the heat pump has to be installed afterwards).

What do you mean by "afterwards"? – and why do you assume a gas heating system for an object that is not yet concrete (I assume you mean a heating system with water in tubular radiators, which would be the same for gas and oil) – have you therefore already narrowed down the property search regarding the age of the house? Many used property seekers also end up with properties from the 1950s and early 60s, which would be a completely different world compared to, for example, a construction year of 1980, as far as the actual heating system is concerned.