ᐅ Small Existing House – How to Expand It?

Hello dear forum members,

I would greatly appreciate your collective expertise! We are wondering about the best way to increase our living space.
We (35, 34, 0 years old) live in a 49m² (527 sq ft) house (built in 1996) on a nearly 900m² (9700 sq ft) plot west of Berlin. We are considering expanding, and here are the options I see:
- an extension,
- demolish and rebuild,
- build a terrace/winter garden plus a garden shed at the back first and continue saving for the house construction,
- or do nothing for now and keep saving.

We have owned the house for a few years; there is still €310,000 to pay off on the mortgage, so we would need a second mortgage for the construction. Here are some details about the existing building: the exterior walls are made of 30cm (12 inch) hollow concrete blocks, the attic is currently not really suitable for conversion, we replaced the gas boiler two years ago with a new one that is oversized. Two houses on one plot are not allowed, so a new building, for example at the back without demolition, would not be approved. There is no formal development plan; instead, planning permission is granted under §34.

Attached is an oriented image of the parcel— the garage at the front has already been demolished, and the green figure is meant to represent a protected tree.

What would be your approach to this? What additional information would you need?
Thank you very much for any suggestions!

I would:

• search for old building plans, make copies, and scan them,
• gather property documents and also copy and scan them,
• investigate the building materials of the cabin,
• mark all incoming utilities on the plans,
• have the condition of the structure (each trade) assessed regarding energy efficiency, structural integrity, future viability, current state, etc.,
• write down the new overall requirements,
• take everything to the architect of your choice.

We can also take a look and provide an initial assessment. However, the evaluation of the condition will most likely require an expert on site.

Maybe you could upload a picture to clarify whether it is a house or a cabin. After the 34er, you could still build larger. However, you don’t just demolish a house from 1996 without good reason. In the end, without an architect who can design an extension of a house onto or around a cabin, it will at least not be feasible from a planning perspective.

Extending the building is definitely the best solution.

K a t j a schrieb:

I would:

• Have the building’s structure (each trade) assessed regarding energy performance, structural integrity, future viability, current condition, etc.

Hello Katja,
Thank you very much for the valuable advice! Regarding the connections, we’ve already found out that the markings in the documents from the construction period, those from the utility provider, and the actual cable locations are all quite different.
I would like to follow the advice to have the house inspected. Should separate appointments be scheduled for each trade, or could one inspector cover all areas?

Hello ypg, the sunlight is currently unfavorable, so only part of the exterior wall is visible in the photo, but it is about a house. It was originally built for a single person, which is why it is so small.

At the time, we hired a structural engineer who also had experience as a site manager and general contractor to conduct an assessment. He went through the entire house and was able to evaluate almost everything and explain what needed to be done. When it comes to precise figures, the respective specialist will have to assess the situation anyway.