ᐅ From what point does it become worthwhile to install a heat pump in an older building?

bestaik schrieb:

Of course, I would also replace the windows here; these are insulated glass windows, so there is even more to do.

bestaik schrieb:

Anyway, the heating system needs to be replaced.

For the design and calculation, I can recommend a good engineering firm. Just search for Ing. Heckmann.
Underfloor heating would probably be installed with a spacing of 7.5cm (3 inches) or possibly 5cm (2 inches). It can work really well.

Replacing windows and insulating the basement are definitely effective measures.

bestaik schrieb:

I thought there might be some general guidelines, for example that a house needs insulation X or not.

No.

Benutzer200 schrieb:

For design and calculation, I can recommend a good engineering firm. Try searching for Ing. Heckmann.
Underfloor heating would probably have a pipe spacing of 7.5cm (3 inches) or possibly 5cm (2 inches). It can work really well.

Replacing windows and insulating the basement are definitely effective measures.

No.

OK, thanks. I’ll contact them. Can anyone roughly estimate what something like this might cost for about 140 square meters (1,507 square feet) of living space?
Mostly there is already screed everywhere, approximately 50 square meters (540 square feet) are still covered with tiles. The living and bedrooms have floating screed.

Or is it impossible to estimate what the cost would be?

Deliverer schrieb:

The search for a gas provider should already give you the answer. ;-)

Basically, every house can be operated with a heat pump. It just varies in complexity. Underfloor heating is already a great starting point. An insulated roof as well. Then make sure there are no drafts anywhere and insulate the basement ceiling yourself from below. After that, properly sizing the heat pump with the help of various forums, leaving out the buffer tank, and you can heat cheaply and environmentally friendly.

It would actually be helpful if you could get some data from the previous owner, such as oil consumption and room temperatures. Then you can make initial rough estimates of how well or poorly the house is insulated.

Built in 1960, the roof will be newly insulated and covered, basement ceiling insulated by ourselves, and windows are neither particularly good nor bad — that’s our starting point. Could you explain why no buffer tank (the heating installer offered/recommended one)? I would like to understand the reasoning behind this. Thanks in advance.

Chrizz72 schrieb:

Built in 1960, the roof is being newly insulated and covered, the basement ceiling is a DIY project, and the windows are neither particularly good nor bad – that’s our starting point. Can you explain why no buffer storage tank? (The heating engineer offered/recommended one.) I would like to understand the reasoning. Many thanks in advance.

And what about the facade? How is it insulated?

bestens schrieb:

And the facade? How is it insulated?

It’s not really insulated, except on the inside with about 2 cm (1 inch) of polystyrene boards. The windows have double glazing (replaced around 15 years ago). Underfloor heating is definitely installed on the ground floor. The first floor and attic possibly have low-temperature radiators or underfloor heating as well. Living area is 170 sqm (1,830 sq ft).

Chrizz72 schrieb:

... which is why no buffer tank.

They cost money, cause losses, and reduce efficiency. Additionally, they are often installed not in series (which is somewhat tolerable), but in parallel, which requires a second pump and leads to many hydraulic issues. They are only installed because previous mistakes were made: hydraulic short circuits, installing individual room controllers, an oversized heat pump...

If the heat pump is properly sized, the rooms do not have thermostats (this is no longer common practice, but that’s a different topic), and you don’t plan to leave multiple rooms unheated at the same time (which is also not recommended), you don’t need a buffer tank. This saves thousands right at installation and just as much over the system’s lifetime.

And yes – heating engineers are often afraid of this. Educate yourself and insist on it.