Construction financing of a two-family house in the second row

Hello everyone,

I have inherited a plot of land on which a house already stands, and now I would like to build in the second row. It is the plot with the house number 12, where the front house already exists and there used to be a barn behind it, which has already been demolished, and I want to build the new house there.

There is no development plan. There will be 2 full floors with a basement. The roof will be a gable roof.
It will be attached to the border with house number 16 (fire protection wall, so that the neighbor could possibly build on it). The neighbor’s barn has also already been demolished.
Since I am inexperienced, I wanted to gather some information here.
First, the topic of prefab house vs. solid house, I am still open on this. I have read that in terms of quality a prefab house hardly falls short of a solid house. However, I have already received some hints that in summer the heat accumulates a lot in a prefab house and the sound insulation is not as good? Is a solid house still that much more expensive than a prefab house? What are your experiences with prefab houses, with which providers have you built (Rhein-Neckar district)? What type of heating do you use? What kind of insulation material would you recommend?
Then the topic of development (infrastructure connection): how is it if the plot is already developed? Is connection made to the already existing supply lines or are new ones laid? How much would it cost? Does the ground necessarily have to be excavated? (From the middle of the street to the new house it is about 35m)

I have also already designed a first floor plan and would appreciate your constructive criticism.


Are 720T€ realistically set for house construction and incidental building costs?
The upper floor is to be rented out, and they would have the attic available as storage space.
Thank you very much in advance!

For the floor plan, it is best to create a separate thread in the floor plan area, with the completed questionnaire.

The topic of prefab house vs. solid house mainly depends on the selection of the specific providers and their particular construction methods. In terms of price, comparable houses are similar, and the time from building permit to moving in is relatively the same. With the prefab house provider, you usually spend more months on hold. Heat is mainly a problem of shading in modern houses. A heavy construction method with high heat storage helps, but you also need to be able to ventilate the heat out again at night.

You can find out development costs from the utility providers. They charge by meters, and at 35m it won't be cheap. Usually, from 15 or 20m of pipeline length, there are also special regulations like a transfer shaft. The utility provider no longer feels responsible for anything beyond the shaft.

On the topic of connection: you basically need a line from the new house to the street for water, sewage, electricity, and telephone. Extending or splicing from the old house is generally no longer done. Soundproofing and thermal insulation can be done just as well in a prefabricated house as in a solid house.

With a basement, it is getting really tight.

What does the building ground look like?

Is there groundwater?

Where are you building? [Scheune] sounds rural?

With today's construction costs, renting out is not profitable. What does the rent index say about the price per m2? Better build just for yourself.

The building area appears to be a village core = "not overplanned inner area" aka §34. You are dealing with the integration requirement and so-called de facto building windows here. I would not rely on this ending only with the barn of No. 18; a safer position would be the footprint of your old barn. Whether it is wise to place a gable end at the boundary is something I mark behind with a man-high question mark. You should also clarify which boundary distances must be maintained: I do not recognize a clear side for the single-sided extension on the plan. However, this does not mean that it would be a wish concert. Make a preliminary building inquiry. And yes, a building ground survey is always recommended.

Renting at 4000€ per m2 construction costs including land and 4% interest. She will never ever calculate that.