ᐅ Garage with hip roof built on the property boundary and ground-level finished floor height assessment at ground floor?

Hello everyone,

I’m currently struggling with the last two questions before submitting the building application.

• Next to the planned townhouse, we would like to have a garage with a hipped roof. This is intended to be a boundary building with a 0.4 m (16 inch) distance from the fence.
According to the Brandenburg building regulations, the average wall height must not exceed 3 m (10 feet). The ground level at the property boundary is at 62.00 m (204.1 feet). The finished screed height of the garage is planned to be 62.25 m (204.4 feet), to keep the height difference to the house minimal. According to the design, the roof ridge will be at 65.55 m (215.2 feet) – so 3.55 m (11.6 feet) above the existing ground level at the boundary.

The architect warned me that even with the very shallow 14° roof pitch, this might not be approved.

What do you think? How is the average wall height calculated? In the worst case, what happens at the building authority – will the application be rejected, or is it still possible to make corrections during the process… something like “trial and error”?

• The ground level at the finished floor level (FFL) of the house basement is causing me headaches. As you can see, we have a slope of 0.50 m (20 inch) over a width of 25.4 m (83 feet). The ground level at the property edge slopes from 62.53 m (205.1 feet) on the left to 62.00 m (204.1 feet) on the right. At the entrance, it is 62.19 m (203.5 feet). The planned finished floor level (FFL) of the basement is set to 62.61 m (205.3 feet) at our request, to ensure no water enters the house. It was important for me to have a 30 cm (12 inch) plinth on the left side. We also want to backfill around with at least 62.32 m (204.2 feet) after excavation.
Is the planned finished floor level of 62.61 m (205.3 feet) now too high? I keep seeing houses with level access to the garden, which I like. However, my family warns me against a step-free exit. After the backfilling, there would be about 25 cm (10 inch) to step out onto the garden. But I’m also unsure about the excavation depths. I was now thinking about lowering the finished floor level to 62.53 m (205.1 feet), but that would probably upset the planner again.

I’ve attached a sketch. I look forward to your feedback.
Thanks and best regards, Redsonic

Hello Redsonic,

Without guarantee, according to BbgBO §6 (8):

In the setback areas of a building, as well as without their own setback areas, the following are permitted even if they are not adjacent to the property boundary or the building:
1 Garages and buildings without habitable rooms or fireplaces, with an average wall height up to 3 meters (10 feet) and a building length per property boundary of 9 meters (30 feet); the roof pitch must not exceed 45 degrees,

The BbgBO came into effect on May 19, 2016; your architect may still be referring to the previous version. The regulations were different then, but in my opinion, your project could have been built according to the earlier version as well.

Your roof pitch is under 45°, so your garage only needs to comply with the wall height limit of 3.0 m (10 feet) — measured locally where the wall is located with the correct height of the ground surface approximately 40 cm (16 inches) from the boundary. If your drawing is accurate, the 3 m (10 feet) limit is narrowly met, so it is compliant.

Only if your garage were longer than 9 m (30 feet) and/or the terrain slopes steeply downward at the rear would this (without a curing easement) contradict the building regulations.

Best regards,
Dirk Grafe

Thank you, that’s already very helpful. At the local building authority, they told me that the roof is included in the wall height calculation. It would be strange if they were mistaken about that.

What happens if it doesn’t get approved like that? Is it possible to make corrections during the process?

The roof is also included in the calculations, which is taken into account in your drawing – the wall height, including the roof structure at the wall, is under 3m (10 feet). In my opinion, the fact that the ridge is higher does not matter.

Of course, adjustments can be made during the process. The building authority must initially provide a written justification if they reject the building permit / planning permission application or request additional information. Once this is received, their reasoning is clear.

Best regards,
Dirk Grafe