Construction costs for a shell structure of approximately 90m2 with a balcony attached to a farmhouse

Good day,

We plan to purchase an old farmhouse. Extension work (brickwork) has already begun there, i.e. the entrance and one room have already been built. We intend to construct an additional floor with a bedroom, bathroom, and balcony. We would carry out the interior finishing such as painting, flooring, etc. ourselves. The roof is already in place as this used to be a barn and it is still in good condition. Gas lines still need to be installed, but they are already available in the main house. Approximately how much would the shell construction for about 90 sqm with a balcony cost? Thanks in advance for the answers. Best regards

Extension work (bricklaying) has already begun there, i.e. the entrance as well as a room have already been built. We intend to construct another floor with a bedroom and bathroom + balcony.

You should first study the plans submitted for the building permit to see how it was intended. The planning should also show how the heating of this extension is intended. Hardly any heating system alone can handle 90 sqm of additional living space from previously generously designed capacities. How far standards for existing buildings can be applied in the whole matter, or whether standards for new buildings must be applied, may also depend on the relative size of the extension in relation to the existing building. Unfortunately, that largely decides on what technical and ultimately also cost level what effort has to be made. Courage and hardworking mates alone are no longer enough with today's regulations.

You should immediately make use of the consulting and planning services of an architect, whom you will need anyway for the preliminary building inquiry and the building application. You must primarily clarify whether and to what extent you are even allowed to build and plan legally.

Even if you plan to convert a barn/stable, the attic, or other outbuildings for residential purposes, this is a change of use requiring a building application, which must first be checked for approval.

I would not overestimate the existing shell construction. The likelihood that it was erected without a building permit is relatively high. Even if it should have a building permit, that does not mean that there is a structural engineering report. And this could, for example, also show that the foundation of the shell was not designed for further elevation. As a rule, such planning ruins are better demolished. This saves the complicated arrangement with a building structure that might have originally started with a completely different design approach, which does not fit your own at all.