ᐅ Wall framing in the upstairs bathroom directly next to the window

As a rule, solar roof tiles are simply connected in series or at most divided into 2-3 strings, or power optimizers are used. However, solar roof tiles are not really a solution for the future; apart from the attractive appearance, there are only disadvantages.

You are right—if you prepare something, you might as well go three sizes bigger. But if, as in the original poster’s case, this leads to a large front wall, then it’s worth reconsidering what you actually need.

Lumpi_LE schrieb:
Solar tiles are actually not a solution for the future; apart from their stylish appearance, they only have disadvantages.

Tesla is also planning solar tiles. We thought they looked quite stylish. However, they are not available yet. What are the disadvantages?

Well, you should be cautious with Tesla. But since the costs are unclear and it's uncertain when they will be available in Germany...

The disadvantages are that it is significantly more expensive with lower yield. Other minor issues include poor maintainability and no additional protection for the roof (fire, damage, etc.).

Of course, it depends on what motivates someone to install a photovoltaic system. My motivation was return on investment, contributing to environmental protection, the enjoyment of using my own electricity, and not spoiling the appearance of the house. An integrated roof solution already ruled out the return on investment.

Lumpi_LE schrieb:
Well, you should be cautious with Tesla. But since it’s unclear what they cost and when they will be available in Germany...
The disadvantages are that it is significantly more expensive with lower yield. Other minor issues include difficult maintenance and no additional protection for the roof (fire, damage, etc.)

Tesla is not yet producing.
The lower yield is an oversimplification. It refers to the yield per square meter. From an economic perspective, optimizing self-sufficiency is more important than maximizing yield. On many roofs, using smaller tiles allows more surface area to be covered—which matches the system’s output.
What maintenance? If a part fails: remove tile, insert tile. Additional effort consists only of 2 plug connections. Cost per tile varies between 15–25€ (approximately 17–29 USD).
In case of fire, a solar tile system operating below 120 V is extinguished. A photovoltaic system with 400 V or more prompts firefighters to let the house burn down in a controlled way.
It’s not true that there are only disadvantages.
It is more expensive, and recent findings show significantly more than 10% higher cost (greetings to Lumpi). That is a disadvantage.

There is no opening planned in the ground floor ceiling; if necessary, it would probably have to be made using core drilling, or maybe the conduit will actually be routed through the wall. So I can still actively decide for or against it. Now that the pipe is located in a rather inconvenient spot, I am leaning toward leaving it out – the chance of installing photovoltaics later on seems quite low. If the empty conduit had been placed somewhere discreet, the situation would look completely different.

Lumpi_LE schrieb:

The wall won’t work anyway; where would the water supply and wastewater pipes for the sink go with only 12.5cm (5 inches)? You’ll have to change that anyway, and then you can integrate the shaft into the wall.
For photovoltaic systems, you need a conduit with a diameter of 32mm or at most 40mm (1.25 or 1.5 inches) that can easily be installed inside any wall—no need for a corner or shaft.

The plumber told me that water supply and wastewater pipes can also be routed inside the drywall partition. For the drain, it probably won’t be a 90mm or 100mm (3.5 or 4 inches) pipe, since a smaller one is sufficient. Two 40mm (1.5 inch) pipes should easily fit within a drywall system with 75mm (3 inch) studs.