ᐅ Home Renovation/Attic Conversion/What Is Allowed? When Can You Convert an Attic?

Hello Forum,
I am a beginner in the interior finishing sector and looking for information. We would like to extend our house. Specifically, we want to convert the attic into usable living space. We have obtained the zoning plans from the city to check what is allowed and what is not.

The documents include the following statement: "For two- or more-story buildings, the maximum permitted roof pitch is 30°. An attic conversion is not permitted."

Question 1: How is an attic conversion defined?
Question 2: Our current roof has a pitch of 20°. If we raised it to the allowed 30°, we would create enough floor area to make the story habitable. Would that be allowed?

I hope someone here can help me. We are at a loss. Thank you.

LittleBee and family

Hello. We have two floors plus a basement. That’s exactly why I’m asking. Because I don’t know what “attic conversion” means in this context. To put it simply: If we comply with the external height and angle requirements, the city shouldn’t care whether we’re just storing boxes there or have a bed set up, right?

Or rather, what makes an attic a converted attic? Insulation? Windows? Laminate flooring and partition walls? Because the space is currently usable indirectly—for boxes and such. However, the height is too low to really create a habitable area. Do you understand what I mean?

Hello,

LittleBee schrieb:

We would like to expand our house. Essentially, we want to convert the attic into usable space. We have now obtained the development plans from the city to see what is allowed and what is not.

The documents state the following: "For two-story or multi-story buildings, the maximum permitted roof pitch is 30°. Converting the attic into living space is not permitted."

We have 2 floors plus a basement. That’s exactly why I’m asking. Because I don’t know what “converting the attic into living space” means in this case. Simply put: If we comply with the height and angle restrictions externally, should it not be irrelevant to the city whether we store boxes there or have a bed? Or not? What makes the attic a conversion into living space? Insulation? Windows? Laminate flooring and built walls? Because the room is indirectly usable as it is now – for boxes and such.
Question 1: How is an attic conversion defined?

An attic conversion refers to the entire attic space that is made usable for living purposes. According to your development plan, this is not permitted for you or the other multi-story buildings in your residential area. I assume you live in 2 full stories, so without sloping ceilings in the top floor?

You would be surprised what matters to the local authority.

LittleBee schrieb:

Question 2: Our current roof pitch is 20°. If we increased it to the allowed 30°, we would already have enough floor area to make the attic habitable. Would that be allowed?

I hope someone can help me here. We are at a loss. Thanks.

I think raising the roof pitch afterward shouldn’t be a problem, although this would require approval from the authorities. The question is whether it is worth pursuing, as 20° is perfectly fine for storing decorations and other items.

Unfortunately, you did not mention when the development plan was issued, nor whether there are already single-family homes nearby using their attics as living space. Before getting your hopes up, you should visit your local building planning office and present your plans. The responsible officer will be able to tell you immediately, based on current municipal decisions, whether you are allowed to convert the attic into living space.

Regards, Bauexperte

Hello!
We are currently living in only one floor of the house. The second floor is also occupied by family members. That is why we want to expand the house upwards.

The building plan is very recent. We received it this week, so I assume it complies with the current regulations.

There are several multi-story houses in our area, some with converted attics. However, I don’t know to what extent those extensions were legally approved. There are also high-rise buildings very close to us.

Right now, we are gathering information to find out if our plan is feasible or not. Unfortunately, we are complete novices when it comes to these regulations, hence my questions.

Changing the roof angle just for storage space doesn’t make sense. That was only an idea to make the attic usable without visually altering the exterior. Since a 30-degree angle is allowed, I don’t understand why the city should be concerned with how we use the interior space now. Can you explain this to me?

We will definitely enquire at the local authority. I just want to improve my understanding and knowledge beforehand to possibly have alternatives in mind. That’s why I am asking here in the forum.

Thank you!

Why does the city care? Because the city doesn’t want a single-family house to contain 200 square meters (2,150 square feet) of living space, resulting in multiple households living under one roof, as in your case. Why not? Because the infrastructure and urban planning may not support it—such as parking spaces and so on.

If your plan is new, you will most likely not get approval. However, if you only received the plan this week but it is 20 years old, you might have a chance. Perhaps urban development has shifted in your favor. Approval could only be granted if your neighbors legally converted their attic space. Unauthorized structures typically do not create building rights for the surrounding area.

The high-rise buildings near you probably follow a different zoning plan. You cannot draw any conclusions for your own building plot from that.

Thank you for the response. However, we want to combine the extension with the existing apartment, meaning we want to enlarge the apartment. We are and will remain two separate households in the house.

I know that there have been several building permit applications in recent years that were rejected. If that turns out to be the case for us as well, then unfortunately the plan is dead. I would never proceed without approval. But I still hope there might be a loophole. After all, we just want to create 2-3 rooms. No dormers, no raised knee walls, no other changes. Simply an increase in the roof pitch to the allowed extent!

Well, on Monday we will call the building authority / planning office to get more information.