Align the idea of DG expansion with the development plan

Hello everyone.

We are considering remodeling the parental house in NRW and are currently gathering ideas because especially the attic conversion proves to be difficult in terms of planning. Maybe you can give me feedback on whether and how our ideas could be in line with the development plan. Or perhaps you have completely different ideas?

I'll try to describe the situation: The development plan allows 1 or 2 full stories. For both variants, it sets permitted roof pitches (+-30°/+-45°) and eaves heights. In the case of the single-story house, the permitted eaves height is so low that the roof basically rests on the ceiling slab.

Given is an older farm house. The footprint is sufficiently large (approx. 170 sqm external dimensions). This could easily be divided so that the older generation gets a separate ground floor apartment and we also have a sufficiently large entrance/living/dining/kitchen/utility/technical area on the ground floor. The problematic part is the attic area. It is already developed above "our" part and has approx. 55 sqm and should accommodate a bathroom, small "office," and bedrooms for 4 people. Due to the sloping roof and the very unluckily placed staircase as a fixed point because of the chimney, the upper hallway takes up a lot of space, so there are only 2 rooms besides the bathroom. A small "office" could somehow still be managed, but a 3rd bedroom is not feasible. Also, we are not fans of roof windows. However, the bathroom, office, and the new room would need to have some.

Since the roof (old roof structure and uninsulated) would have to be replaced anyway, our idea is to raise a high knee wall (so basically 2-story) in that part of the building to get the rooms. The larger rest of the house should remain without a knee wall. The problem seems to be that the house is still considered single-story because of the ratio to the footprint, and the knee wall on "our" part of the house would, according to my understanding, violate the development plan.

Am I seeing this correctly, or could one perhaps do something towards the knee wall? Or does anyone have completely different ideas? Ultimately, we will also ask the architect when the time comes. A last resort would probably be to continue the attic conversion several meters above the apartment of the older generation without a knee wall and have to make do with roof windows. That part of the attic is currently designated as agricultural use (hay storage).

Thanks for your opinions Replica

The development plan

being fully provided in image and text would be indispensable for helpful assessments.

allowed roof pitches (+-30°/+-45°)

Negative roof pitch?

is the permitted eaves height so low

How low? Which reference point?

Given is an older farmhouse.

Then give it to us. The complexity of a floor plan is hardly describable in words.

The large rest of the house should remain without a knee wall.

Why? Is the roof structure new and insulated here? If so, how long ago? Is it allowed to install dormers?

The problem is probably that the house is still considered single-storey due to the relation to the footprint

For that, one would need to know the age of the plan, since the applicable full-storey definition depends on it.

Ultimately, we will also ask the architects about this

Good idea. Especially when building on existing structures, an experienced planner can assess possibilities for exemptions from development plan regulations.

Generous dormers, if permitted.

Negative roof pitch?

I formulated it too imprecisely: 2-story: 30°, 1-story actually 48°. Each with a tolerance of ±3°. Currently, 45° is built.

How low? Which reference point?

Eaves height is fixed at 2.75-3.00m above top edge of the plinth.

Then give it to us. The complexity of a floor plan is hardly describable in words.

I have attached the floor plan of the attic. The room at the top left is the bathroom, although it is labeled as a bedroom on the plan.

Why? Is the roof structure new and insulated here? If yes, how long ago? Are dormers allowed?

The plan is from 1978. At that time, a 5-meter L-extension was added to the house at the bottom (relative to the floor plan, which is also south). Otherwise, the house and the roof structure are almost 90 years old and uninsulated. As far as I know, dormers are not excluded in the development plan.

Generous dormers, if allowed.

Seems like a good idea. We already discussed that yesterday.

This will not work. Cropped attic floor plan, no ground floor plan, no development plan, no site plan, and vague information about the planned renovations.

Do I understand you correctly that only the already developed part is to be renovated, and the rest is to remain unused?

Then the definitions at that time will probably not allow a full floor: