Renovation assessment of 1980s solid house

Really difficult with the budget. Regarding the electrical system, check how your sockets are connected, whether the PE and neutral conductor are really connected separately. If yes, then the electrical work is quite cheap, as you only need to retrofit the RCD in the distribution board. If no, complete rewiring is necessary. Given the year of construction, it should actually be fine...

I would tear out the screed and install underfloor heating, but that would blow the budget.
Otherwise, everything has basically been said. You just have to set your priorities. If the facade can be insulated with blown-in insulation, that would of course be the jackpot.

Budget and demands just need to be balanced a bit. You have enough budget. In principle, you don't need to do much technically to be able to move in. The idea to take care of some things in advance is logistically correct and financially demanding. My priorities would be to adjust the aesthetics to your own taste Ceilings, floors, windows (including the energy aspect here), bathrooms. Also ensure electrical safety --> installation of RCD. Everything else can wait if the budget is tight and functionality is given. The heating is basically new. I wouldn't tear it out - unless underfloor heating is a "must" for you. Then consider the costs and possibly look for another property. You can do intermediate insulation in the roof when you live in it. You can include water pipes in your insurance. As long as there is no defect - leave it for now.

The inspection with the building expert revealed:

[*
Exterior facade in good, very good condition. There is a beam in the half-timbering (which is only for appearance, not load-bearing) at the base on one side that "someday" could be replaced
[*]Roof looks good & tight, estimated to last another 30-40 years
[*]Windows are also fine. He would advise against replacement. Although my wife would like to replace them
[*]Electrical wiring is done with 3 wires, also up to the outlets. Recommendation: Talk to an electrician about installing 1-2 RCDs to possibly cover rooms.
[*]Roof insulation was done with white stone wool (angel hair?). You have to be careful if you want to change it.
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[*]He also questioned whether I really want to replace it, as the savings compared to newer insulation with the same thickness are probably limited


[*]Hot water storage tank might need to be replaced in 2-4 years

Overall, the expert expressed no concerns regarding a purchase. I am now a bit puzzled why the gas bill is at 36,000kWh, since the roof as well as the facade show (minimal) insulation. Apart from that, I am really optimistic.

I am now a bit puzzled as to why the gas bill is at 36,000 kWh, since the roof as well as the facade have (minimal) insulation.

It is and remains an old house with practically no effective insulation. If you also want to keep it nice and warm from autumn to spring and possibly often ventilate at the same time, that is no surprise.

Overall, the expert did not express any concerns regarding a purchase. I am now a bit puzzled as to why the gas bill is at 36,000 kWh, since both the roof and the facade have (minimal) insulation. Regarding the rest, I am really optimistic.

Your house is rated at 229 kWh/sqm. Not a top value for the time but within a comprehensible range. The energy certificate assumes standard temperatures: 20 degrees in the living rooms, 24 in the bathroom, 17 in the hallway. Mathematically, with 125 sqm of living space, you would come to a "standard consumption" of 28,625 kWh. Now comes the behavior of the residents. Anyone who wants 23 degrees room temperature quickly has about 25% higher consumption, then you would already be at around 36,000 kWh. points this out exactly. Of course, with disciplined behavior, you can also get below the standard mark without it becoming uncomfortable. The more people in your household leave the wrong doors open and turn up thermostats or (like my British-influenced family members) absolutely love to keep windows permanently tilted open, the more worthwhile investing in insulation becomes.

On the whole, the expert did not raise any concerns regarding a purchase. I am now a bit at a loss as to why the gas bill is at 36,000 kWh, since both the roof and the facade have (minimal) insulation.

You can try entering the wall construction, windows, etc. into Ubakus. There you can also relatively easily simulate what potential insulation, new windows, etc. would bring. It might be worth taking a look at it.