Complete renovation of a single-family house built in 1960 on a slope

In your listing, I cannot spot any errors and nothing comes to mind immediately as missing.

You are revisiting the photovoltaic system. I recommend coordinating it well with your own consumption. Regarding storage, I would not go for a DC-coupled storage like in our house and also commonly used, but rather provide the space and connection for an AC-coupled storage that can store not only the photovoltaic power but also, in combination with a spot market tariff, power from the grid. The nice thing about this is that these systems can be retrofitted very simply. Just keep that in mind and it will be fine.

But do me a favor and don’t put plastic in your house. That is – no offense – social housing level for rental apartments. For the material costs, you can almost get parquet if you look a little.

I thought that too – with the difference "Do yourself the favor"...

I cannot see any mistakes in your list, and nothing is coming to mind immediately that is missing.

Thank you very much for your effort, that reassures me along with the previous statements from the forum colleagues!

The biggest concern was about the costs of underpinning the foundations and properly sealing and insulating the new floor slab. You often read truly horror stories about that online.

You are still revisiting the photovoltaic system. I recommend coordinating it well with your own demand. Regarding storage, I would not go for a DC-coupled storage system as in our house and as is generally still common, but rather plan the space and connection for an AC-coupled storage that can store not only photovoltaic electricity but also, in conjunction with a spot market tariff, electricity from the grid. The nice thing about these systems is that they can be retrofitted very simply. Just keep that in mind and it’s all good.

The photovoltaic system is planned on the two dormers. One dormer faces south with about 32 m² area, the other faces north with about 28 m² area. Both dormers will have a 25° pitch; in addition, there will be modules on the south balustrade of the balcony, so I will come to a total of 5-6 kWp (losses on the north side already roughly accounted for). Since I am doing it all myself (except for the substructures on the roof and the tight cable feedthroughs, which the roofer will do), it could almost be economical. But that is actually not particularly important to me; I care about a certain degree of self-sufficiency and ecological aspects.

Regarding storage, "stackable" battery systems are now available. So I will start with about 6-8 kWh and can then add more if necessary. I take the hint about AC-coupled systems because it could make sense concerning future smart-grid applications and corresponding tariffs.

That’s what I thought too – with the difference "do yourself a favor"...

Noted, instead of laminate a proper parquet floor will be installed. It should be nice and durable.

So I will start with about 6-8 kWh and can add more if necessary. I take note of the tip about AC-coupled systems; it could make sense regarding future smart-grid applications and corresponding tariffs.

You will not be able to get a typical storage system that is smart-grid-capable later on. Better start right away with a suitable system or keep the budget for later. In my assessment, with some industry knowledge, the price development for smart-grid storage systems in the next 2 years will be consumer-friendly enough that there will be little difference compared to a simple DC-coupled storage system.

I will install a combination of a Loxone system (completely wired via Ethernet cables) and a KNX system (for certain autonomous functions such as ceiling lights in case of a failure of the Loxone system). Interfaces to, for example, the heating or ventilation system will probably be created via a Modbus (or similar). This can also be used to set up intelligent load management including battery storage, a charging station, and a heat pump. That is what I mean by "Smart-Grid." The switching/control of controllable consumption devices in the sense of §14a or the use of variable electricity tariffs (TAF2 in SMGW) is independent of this and will probably be handled via the Smart Meter (sometime when all the skeptics are gone and it is finally implemented in most households). I myself once worked at an energy provider in the smart metering sector; that was and still is a hassle.

For me, it is first about optimizing my own consumption and a bit of tinkering. I deal professionally with all kinds of industrial bus systems and can also do a bit of programming. So the entire energy management and home automation system will be my future toy, with which I will occupy myself in my free time. I am also happy to spend money on it if it engages me. So it does not have to be economical (if it is, all the better).

However, none of this is decisive for the calculation I am currently facing. First, I have to finish the house; the tinkering will come at the end if there is still money and nerves left.

Wow, super interesting and a very solid cost breakdown. I come from the field and can tell you that you are very accurate with many of the figures in your breakdown!

Good luck!

that you are quite accurate with many figures in your statement!

Thanks, that’s encouraging! Do you see any major discrepancies anywhere?