What should be considered in a 35-year-old house?

Hello,

we are considering buying a 35-year-old detached single-family house (solid construction, renovated tiled stove, new gas heating, underfloor heating, no heat pump, no solar system on the roof, basement/ground floor/1st floor/attic, windows with double glazing).

What foreseeable costs/repairs/renovations come with a 35-year-old house? Is it absolutely necessary, once the gas heating breaks down, to install a heat pump including all necessary conversions in the future? What should definitely be checked/possibly renovated before purchase/move-in (roof, water pipes, etc.)?

A few keywords are sufficient for me so that we can research further independently. Thank you!

R.K. Weiss

What foreseeable costs/repairs/renovations come with a 35-year-old house?

It's not that much: according to the new Building Energy Act, as a new owner you have to insulate the top floor ceiling and the basement ceiling towards the living space (basement ceiling) or the attic and the heating pipes.
You can look it up on Google.
You _can_ do windows and facade insulation.

Is it mandatory, once the gas heating breaks down, to install a heat pump including all necessary conversions in the future?

When that time comes, you can also consider new electrical wiring, pipes, and technology, and possibly apply for a subsidy for that. But it doesn't have to be done yet.
I would still inspect the house with an expert/appraiser/professional before the purchase. Especially in the 90s, paneling etc. was used, which hides many defects. A basement can also have damages. Possibly an energy consultant?!

From 1995, rather 1996, the technology for windows changed (gas instead of air). That makes quite a big difference, but if necessary, you can just replace the glass if the window frames themselves are in good condition. The network will probably not be installed... but is it needed? Underfloor heating is not bad at all, but in the 90s with larger spacing. But why not? The house will be very livable, also in the next 20-30 years (minimum!). During that time, you will probably redo the bathroom once and replace the heating once. If the floor plan, location, and price are right... A surveyor makes sense!

Is it mandatory that as soon as the gas heating breaks down, a heat pump including all necessary modifications must be installed in the future?

In the short term no, in the medium term it will probably come down to district heating or a heat pump. However, the modifications should be limited if underfloor heating is already installed. According to the Heat Protection Ordinance 82, 150 kWh/sqm heating demand is permitted, and solid constructions from that time probably also reach this limit. With new windows, however, you can save quite a bit of that again.