Encroachment on the neighboring property

Hello everyone,

we are building an end-terrace house with a basement. The building permit for the construction of the house was issued in December 2016. The plot on the left side of the property already has a basement, so there is no problem with the excavation of the foundation pit since we are not digging deeper.

On the right side of the property there are garages. According to our architect, these must be underpinned. A total of three garages belonging to three different owners need to be underpinned. One of the owners has already refused their consent.

I had a conversation with a lawyer about this. He said that according to the [Nachbarschaftsgesetzt] we do not need the neighbors' consent. 1. otherwise there is no other way to build the basement without losing square meters 2. there is a building permit According to §16, only a notification 30 days before the start of the construction work is necessary.

How would you proceed here? I count on your numerous comments and support.

Best regards Michael

we are building a corner terraced house with a basement.

This introduction confuses me: I know terraced endhouses, they are located at the ends of a row of terraced houses (which are typically built "all at once" and usually by a property developer. There is usually also a shared garage courtyard nearby, often behind the garden fence of one of the end houses. I can imagine less what a terraced cornerhouse could be: it could be a corner house in a block of houses in a "continuous" row development – but that was rather done with multi-family houses (?). Therefore, the situation is somewhat unclear to me. A contrary case (semi-detached house without a basement, neighbor still unknown) is currently being discussed by kamda here (and also in the "green forum").

The main question is about the refusing neighbor, right? As already mentioned, you don't have to care what he says. Only if damages occur during construction do you of course have to pay. Extensive documentation before starting is important.

On the right side of the property there are garages. According to our architect, these need to be underpinned.

The question arises: "why?" That is, what is the damage to be avoided – that these garages settle during your excavation, or that they (if nothing stands between) later push against your house?

Thanks so far for your feedback.

The other houses in the row were already built around the 1970s. So we are building into a gap between buildings.
Left: House with basement
Right: Garages

The danger if we do not underpin the garages is that they will slide into the excavation pit since we are building a basement and the garages only have an 8 cm thick foundation.
Homeowners' liability insurance is in place.

Our house will be placed directly on both sides of the property boundary next to the neighboring buildings or garages.

The settling of the garages will probably be unavoidable. The question is whether we need the neighbors’ permission to carry out the underpinning.
In our opinion and according to the Neighbor Law NRW §22, permission is not required, but a written notice of 30 days must be given to the neighbors.

8cm foundation? Or are you confusing foundation with floor? Normally, garages also need a somewhat stronger foundation to stand on. This applies to both prefabricated garages and solidly built garages.

What kind of garages are these?

In any case, you should take enough (many!) photos from all possible directions and angles, just to be prepared.