Fire protection terrace roofing semi-detached house

Hello everyone,
we have built a semi-detached house. First, our neighbor of the semi-detached house built a terrace roof with a width of 6 meters and a depth of 3.50 meters directly on the property boundary. Afterwards, we built a terrace roof not directly on the property boundary but with about 24 cm distance from the property boundary. That means both terrace roofs do not directly border each other. Both terrace roofs consist of an aluminum frame and glass roof – no highly flammable materials. However, our neighbor has now erected a privacy screen made of wooden material up to a height of 2.50 meters reaching the end of the roof directly on the property boundary. But since this is the south side, we do not want a high wall in front of the living room. Unfortunately, the city has now contacted us and written the following regarding fire protection. We would like to seek advice here in the forum – is it really necessary to build a fire protection wall? We live in Baden-Württemberg.

See the city’s response:
You must let go of the idea of a "fence". The regulations on fencing in the Neighbor Law and in §6 of the State Building Code do not apply to the dividing wall WITHIN the main building. The covered terraces in this case must be viewed as part of the main building. Normally, these – just like the main houses – must comply with the regular setback distances according to §5 of the State Building Code, i.e., at least 2.50 m from the property boundary. However, the setback distances may be waived if there is mutual building on both sides. A semi-detached house is naturally always built on the boundary against another semi-detached house. Thus, §5 Para.1 No.2 of the State Building Code is applicable (mutual building). Perfectly matching mutual building is not necessary. An offset between mutually built row and semi-detached houses is not unusual. Building height and building depth can differ by a few meters.

BUT: Between the covered terraces, a fire protection separation in the form of a fire wall or building end wall according to §7 Para.3 No.2 or 3 LBOAVO must be installed, analogous to the main buildings. Especially if everything is now to be stuffed with furniture and storage shelves/cabinets containing partially flammable materials and access and visibility are thereby restricted, this is all the more important. Otherwise, fire can spread from window to window over flammable furniture from one house to the other. Fire would only be noticed very late due to the placement of cabinets and partitions.
This fire substitute wall must have at least F60 quality. Alternatively, for drywall separation, a layer structure can be used that has F30 quality on the inside (neighbor side) and F90 quality on the outside (your side).
The plywood board does not meet this requirement!

The latest amendment of the LBOAVO (Implementation Ordinance to the State Building Code BW) has made a follow-up regulation. According to this, a fire wall can now be waived if the terrace roofs are not deeper than 3m. Unfortunately, this is not the case here, since the depth is 3.50m.
The obligation to erect a fire substitute wall according to the provisions of §7 Para.3 No.2 or alternatively No.3 LBOAVO concerns not only your neighbors but also you. Strictly speaking, you AND your neighbor must each construct such a "building end wall/fire substitute wall" on your property sides, separated by a 2cm joint (fire wall-joint-fire wall).
For pragmatic reasons, we also consider the fire protection issue resolved for the terrace if you and your neighbors agree on a shared dividing wall that protects both sides. Whether this then stands on one property side or centrally on the boundary is unimportant to us. How you settle this civil law-wise due to customary law and encroachment, etc., we leave to you.

Requirements:
· The requirements according to §7 Para.3 No.2 or 3 LBOAVO (fire substitute walls, building end walls) apply.
· The fire substitute wall must be at least fire-resistant (F60 quality). Alternatively, it can be constructed as drywall if it has fire resistance class F30 on the inside and F90 on the outside. Weather-resistant fire protection boards approved and built according to manufacturers’ guidelines, e.g. Knauf or Fermacell, must be used. For simplicity and due to weather conditions, we recommend a brick variant with F60 quality in this case.
· The wall must completely close with the roof (no gap between roof and wall). If necessary, it should be carried up to the upper edge of the roof and finished with a sheet metal cover for weather protection.
· Unlike proper full-value fire walls, a fire substitute wall can waive "mechanical resistance". That means it does not necessarily have to remain stable even if the burning building has collapsed or burned down.

Thank you in advance for your information!

Thank you very much in advance for your information!

Unfortunately, the city has now gotten in touch

On their own or did you inquire because you don’t want the neighbor’s wall?

He who digs a pit for others often falls into it himself. I can't say more about that.

Oh man… now you have it in writing from the building authority. I cannot contribute anything technically. Don’t you talk to your neighbor? Who keeps 24 cm distance from the boundary? That a privacy screen is erected between semi-detached houses on the terrace is common. It should be discussed beforehand and considered when buying the semi-detached house.