Purchase decision small semi-detached house 100 sqm from 1930

Before we do that, an energy consultant should advise us first. Is he the right contact person for this?

Are we taking on too much, or how do you see it? We don’t have children yet and would try to put in as many hours as possible after work and on weekends.

Hello Finch,

I first join the others and also have a strong tendency to say: "Buy it."
The main reason is that when selling within the family, you could assume that you not only get an attractive / fair price but above all are not being deceived regarding condition, technical / legal / neighborhood problems, etc.
However, as long as you don’t provide us with photos and plans, we can only comment on this with rough (and apparently consistently positive) assumptions.

One thing upfront: In a comprehensive renovation of a semi-detached house, the character of both halves must remain similar afterward. This criterion is interpreted extremely differently by building authorities. Sometimes not even a sarking insulation (let alone dormers) is allowed, sometimes the one half ends up visually having nothing in common with the other.

Regarding living space:
It was already mentioned that you might gain some space with dormers, maybe also with a small extension. But even with 100 sqm, in my opinion, you can live well with 4 people if you adapt the layout accordingly. You have to give up the fashionable concept of "open living," which, in my perception and after Corona, is on the decline anyway. It is important that every family member has retreat spaces. To illustrate: 2 children’s rooms with 10 sqm each are much more valuable than just one with 20 sqm. This also applies to other rooms (home office, etc.).
Here in the forum you will certainly get valuable tips for the best possible use of space after you upload a first draft of your intended floor plan.

I’ll summarize what construction issues I have encountered with houses from the 1930s – and will organize this according to “fixability”:

WELL fixable within a core renovation:
1) unsuitable floor plan
2) lines (electricity, water) not running in installation corridors
3) asbestos was barely used in the 30s but often found in later conversions.
4) damp basement (often built directly against the earth without waterproofing)
5) roof in poor condition
6) poor energy performance
7) roots of old trees grown into masonry or sewage pipes
8) badly documented house, especially (but not only) due to subsequent changes

POORLY / NOT fixable:
a) weak sound insulation to neighbor, probably 24 cm partition wall (possibly even thinner). Facing walls help a bit (especially if the neighbor cooperates and installs them too), but against continuous components like beams there is little you can do.
b) wooden beam ceilings with their typical problems (poor noise protection from upstairs to downstairs, vibrations, sometimes creaking)

And finally something positive: Such a house has a soul. This can never be achieved with a new building.

6) We want to get the maximum out of it as cost-effectively as possible – basement ceiling, roof with external insulation, windows ... We are still clueless about the heating. There is a functioning oil heating system installed, not that old. Of course, that has no future ... The idea is to first reduce consumption as much as possible through renovation measures. Then, with supplementary heating systems (domestic hot water heat pump, photovoltaic), rely even less on oil. But as I said, I really have little knowledge about heating.

If you renovate so well anyway, then it makes no sense at all to still use oil. Install a simple heat pump and enjoy very low heating costs.

Problem is that we don't yet know for sure if we can install underfloor heating due to the build-up height...