Extension of residential house in bungalow style - increase roof pitch?!

Hello,

In 2016, we built a residential house (L-shape) in bungalow style ( standard). The house has about 170sqm , is equipped with a reinforced concrete ceiling and has a hipped roof construction with an extension made of glued laminated timber with a 30-degree pitch. The attic was originally intended only as a storage area and was completely sufficient for that. Now we want to convert the attic into a living area, which was not planned before. Unfortunately, the height is insufficient for this. We have considered solutions such as a hydraulic (which is not an option for us) or raising the knee wall (so far there is no knee wall at all). But both options are probably not feasible for practical reasons (structural issues?! and rather cost reasons). So far, there is a foldable attic ladder, but we have already planned a larger opening in the reinforced concrete ceiling for a real staircase (which is now covered). The possible knee wall raise I asked about in another thread – but that will probably not work. The structural integrity and base are too risky there. We want to use the roof as expanded living space (child) within the next 1-2 years, but the current condition is too small or too low for that. The usable area – now about 65sqm – should then be around 90-120sqm. (Total house area on the ground floor with L-shape is about 170sqm). The question is whether it would basically be an idea to "rebuild" the roof from the current 30 degrees to 45-55 degrees pitch. In doing so, we could also retrofit several windows (there is currently only one) and possibly also install a photovoltaic system at the same time. One idea would be to use the long "L-section" as a living area and the shorter part rather as a storage area. Although it would certainly look strange to change only the long part and leave the short part as is. The current brine heat pump has the necessary reserves. The surrounding residential houses all have slopes up to 55 degrees. Basic opinions without detailed floor plans and calculations would be appreciated. Thank you very much!

What is your current interior height up to the ridge purlin? We also have 30 degrees and decent heights in the middle of the attic. I can well imagine mostly leaving the roof as it is, installing dormers, and separating the lowest parts as knee walls.

I would
1. Have a structural engineer look at the building documents, the strength of the foundations, the strength of the stones for the additional loads.
2. Consult a local carpenter or roofer, and just tell him,
I want two rooms and a bathroom up there, and let the professional lead.

What is your current interior height up to the ridge beam? We also have 30 degrees and decent heights in the middle of the attic. I can well imagine mostly leaving the roof as it is here, installing dormers, and separating off the lowest points as knee walls.

In the middle of the long L-shaped section, the height is currently about 2.2m. At the moment, there is only insulation on the reinforced concrete ceiling with OSB boards on top. If we build a proper floor structure with underfloor heating there, we will lose height again. Overall, the usable space will always remain very small.

PS:
3. Check the development plan to see if you are even allowed to increase.

Small rooms do not necessarily have to be created, therefore carpentry, there is enough space.
And be open to solutions, the house will look different.

PS: 3. check the development plan to see if you are allowed to increase at all. Small rooms do not necessarily have to arise, therefore carpentry, there is enough space. And be open to solutions, the house will look different

yes that is correct. Of course we have to clarify the official matters, as well as the structural engineer, etc. We are aware that the appearance of the house will change. Whoever wants one thing must like the other.