Cost estimation for an extension to a new building

Thanks for the compliments, I had only looked at your floor plan here and read your information about the construction in 2017, which I naturally do before giving an answer.

Just like ypg, I also wonder how the access to the extension is supposed to be made, to the west is completely bathroom, dressing room and master bedroom? An extension on the ground floor would certainly be cheaper to build than an elevated one on the upper floor.
The forum will surely have good ideas for the floor plan as soon as you present suggestions.

Good luck & strong nerves with the little one!

Access could be through the dressing room. Not ideal...

We are also pretty much at the beginning of our considerations. We also still have the option to go for a complete new build, as there is still a plot available. But the current construction prices are simply insane.

in 2017 we built ourselves a wonderful house in the style of a city villa to live there with our 2 children plus a "spare room." God has richly blessed us and in 2021 we had twins again.
There is a lack of a room and generally space. We would like to aim for an extension with timber frame technology.

I assume that we are talking about this house , and that with

About 35 sqm are to be created on the upper floor. The upper floor would protrude over the driveway and would have to be supported.
We would prefer not to build a flat roof, but rather to "extend" the existing roof in order to better use the . For this purpose, a staircase is to be installed in the extension, since so far we only have a pull-out attic ladder.

it is meant to build over the boundary setback with living space (forget it!). By the way, in the area of the desired extension, a staircase would also rise in an area critical with respect to standing height. The choice of a single-flight straight staircase also backfires here as does the hipped roof.

Economically, technically, and legally I see the bold plan doomed to fail, and a change of property more obvious.

I have attached from the aerial image where I rather see extension potential: namely into the garden area. The building depth of neighboring buildings 26 and 10 gives hope that this would at least be feasible regarding building boundaries:

An extension on the border garage?

I have already had a preliminary discussion with the building authority regarding our project. As long as I maintain the minimum distance of 6m from the neighboring building, many things can be discussed since our situation is understood.

Whether this commitment will ultimately be kept, I do not know now, of course.

Then you should set back at least 1.3 m from the boundary. It’s best to talk to the neighbor first. If they give their OK, I see good chances.

My neighbor also submitted a building inquiry with lots of deviations from the development plan. Received a positive decision.

Off to the architect. They will manage it. An oral opinion from the building authority is worth nothing.

Sorry. Back to the topic. You should calculate with 100 k.