Partial renovation of terraced house financial framework

Whatever I’m supposed to have to do with the fact that there is no gable-side roof overhang

I must have mixed something up there

The exterior walls are Poroton. But well, it seems that ultimately only an energy consultant on site will be able to assess that.

A note I would have appreciated :) We also have a mid-terrace house from the 80s. Also staggered. Where is north on your plan? For us, the protruding corner is to the north. Since we have the bathroom in the north and moved the shower into the corner, we had the issue of condensating moisture in the corner and on the ceiling. We have now managed it with the roof insulation and a retrofitted ventilation system. But it would have been easier if someone had considered it.

Exterior walls are Poroton. But it seems only an energy consultant on site will be able to finally assess that.

For construction year 1978, the first WSchVO already applied, which prescribed a minimum thermal protection of the building envelope. Facade insulation for houses from this construction year rarely pays off, especially if roof overhangs need to be extended for it. Poroton at that time had a lambda value of about 0.2-0.25 W/mK. This results in a U-value of about 0.7 to 0.8. This is not new construction, but does not justify the effort of facade insulation as a single measure. At most, you can achieve about 0.2 W/m²K, equivalent to a reduction of 0.5 W/m²K or about 35 kWh per m² annually.

Overall, I find the planned measures sensible. Cost-wise, it depends strongly on the proportion of own labor. For bathroom and kitchen, I can say little; what companies charge there also depends heavily on the equipment. Flooring ranges between 30€/m² (vinyl self-installed) and 90€/m² (hiring out parquet installation).

The heat pump (5 kW model) including installation will probably be around 20k (material with DHW storage is 8k, 40 hours of installation, and the rest is for the boss’s SUV), plus the underfloor heating and distribution, probably totaling 40k.

The windows made of plastic will cost about 800-1000 €/m², if no complex sliding doors are included. For wood, about 500€ more per m².

I would also replace the interior doors right away, not later. That is 400€ material per door including frame. Can be done yourself if the shell construction is not too crooked or dimensions don’t deviate.

I would reconsider central ventilation; you have to find space somewhere for the ducts. Possibly decentralized with heat recovery. Decentralized single systems (e.g., Zehnder Comfo Air 70 or comparable) offer the option of connecting adjacent rooms. One device in the living area connected to the guest WC, and one in the bedroom connected to the bathroom would be a simpler option. There are also decentralized systems with alternately supply and exhaust air, but I am always skeptical about those, and you also get supply air in the bathroom with the corresponding odor spread.

Regarding funding:
If KfW efficiency house, you would need to achieve at least KfW85 EE. This will fail at the basement ceiling and facade. The eligible measures besides the heating would only be ceiling insulation and window replacement, therefore limited, and the costs for the energy consultant also rise. Moreover, the heating can then only be funded via the KfW loan, while the BEG single measures funding offers the higher amount here.
So:
Heating with ancillary work via BEG single measure
Windows also as a single measure with 15% grant
Ceiling insulation done yourself without BEG. The cost for the energy consultant here is probably as high as the subsidy.

[FUNDINGWISE:]
If [KfW] efficiency house, you would have to achieve at least [kfw85 EE]. However, this will fail at the basement ceiling and the facade. The eligible measures besides the heating would only be the floor slab insulation and the window replacement, therefore manageable, and the costs for the energy consultant will also increase. In addition, the heating can then only be subsidized via the [KfW] loan, while the [BEG] individual measure funding provides the higher amount here.
So:
Heating with ancillary work via [BEG] individual measure
Windows also as an individual measure with 15% grant
Floor slab insulation as own work without [BEG]. The costs for the energy consultant are probably as high as the subsidy here.

For the efficiency house, the following would be eligible for funding:
- necessary gutting and disposal
- insulation and windows
- heating including underfloor heating
- reconstruction of floors including screed and parquet/tiles
- possibly plastering work due to installation of [ERR]
- possibly new doors due to changed build height
...
Own work is also eligible for funding – so insulating the basement ceiling yourself will be subsidized for the material share.

With [BEG EM], the restoration of the floors, for example, is not funded.

As said, you have to have it calculated once. Extremely cheap loan along with repayment grant should not be underestimated.