Semi-detached house on a plot with rising ground

Depending on the length of the front garden, you elegantly knock off the 30 cm, and regarding the drainage channel, I agree with my predecessor.

To be honest, I understand the neighbor who thinks of so many things during construction and does not also consider the height measurements of the not yet "concretely existing" neighbor. For precisely such banal reasons, I generally consider it a "design flaw" to build semi-detached house plots uncoordinated.

The 30 cm lower level on your side doesn’t seem to be a real problem to me.

Yes, I do see that as a problem. We are below the backwater level. I don’t want wet feet on the ground floor! According to the general contractor, that’s definitely not an issue. The house definitely needs to be raised. In my opinion, the goal should always be to get the house as far out of the ground as possible.

I can’t really imagine a 30 cm height difference across a house width visually without stepped houses

That’s how I see it now, too. I hope the guys from the building authority see it that way as well. Whatever the development plan says. I personally don’t see this as an exemption, because I am not "breaking" the development plan to have something special, but because the conditions on site don’t allow it any other way. A discussion with the neighbor, also considering that your building application is almost through, I consider out of the question. They want to start building in April.

According to the development plan, the semi-detached house should form a visual unit (the definition here is quite flexible) and in any case be the same in eaves height and ridge height.

I see you continuing the neighbor's roof at eaves height and pitch and practically also the house depth.

You can now either dig in your ground floor by 30 cm (which I wouldn't like), or make your house 30 cm lower from the ground floor base compared to the neighbor's. That means accordingly less knee wall in the attic or reducing all room heights up there correspondingly, as far as possible.

What does the building line say, is there one, or could you also shift the house in depth so that the roofs, despite the height offset, practically reach the same level?

It would be helpful if the neighbor would be so kind as to share their plans with you. Or even kinder, if you could show them here, then we could work out the best solution together.

I recommended here two weeks ago to someone in a similar situation the "radical solution," simply to use the same planner as the neighbor. That would probably be a banal but effective way to perfectly fit at the "interface."

: Thanks for your tip and also the link. I skimmed the topic. Basically, we have a similar situation, but in our case the train has long since left the station. Our general contractor's architect is planning, our semi-detached house partner is planning with a freelance architect. The issue with the height and thus the 30cm reduction in ceiling heights per floor has also occurred to me. But since I am tall, that is not an option for us. I don't want a second-choice house now either because of the neighbor situation, but a fair solution. I bought our plot with the same rights and not less favorably. For me, the only option is actually "to build higher." Our general contractor wants to approach us about this on Monday. Let's see what solution he offers.

The issue with the height and thus the 30 cm reduction of ceiling heights per floor has also occurred to me. But since I am tall, that is not an option for us.

*smirk* Are you really so tall that 250 instead of 260 cm ceiling height would cause you to bump your head?

For me, only the solution "build higher" really comes into question. Our general contractor wants to approach us about this on Monday. Let's see what solution he offers.

One should always take a look at the development plan oneself. A building line could spoil my suggestion, as is not uncommon with row houses on slight slopes, to translate the height offset also into a depth offset and thus align the roofs over the largest part again despite identical actual house heights. That would mean about 50 cm depth offset at 30° pitch.