So, we are finally a step further. Unlike initially 50sqm, we have now ended up at 99sqm (internal dimensions, still without deduction of interior walls). It was probably similar with .
Construction method: timber frame or solid. I tend towards solid with Poroton bricks and a slab foundation. I haven’t calculated the price differences to the originally planned variant with point foundations and timber frame construction yet, but it will be large. Whether I do the slab foundation myself is also a topic we are not clear about yet. Shells, reinforcements, etc. you can manage, but properly laying the house connections worries me. If you do something wrong there, you won’t get to the respective spot quickly or cheaply anymore.
Otherwise, only roof surcharge, electricity connection to public grid, and window installation (possibly also as own work) are to be contracted out to craftsmen.
Dimensions are 8m x 14m with rafter gable roof, single-story.
We are still not quite sure about energy for heating and hot water. I prefer electricity for everything because, firstly, well insulated, secondly, no gas connection necessary, thirdly, solar system could be connected and if underfloor heating is also electric, it gets warm immediately. Disadvantage or question: won’t electricity get incredibly expensive, even with night electricity use? Since we will have many south-facing windows and only kitchen, bathroom, and guest WC have to be heated on the north side, while rooms on the south side will already be warm enough without heating, I tend rather towards electricity (if that’s not enough, a gas connection can be installed afterwards).
Roughly calculated, I end up at 1,700/sqm without craftsmen, although I have certainly estimated some items rather generously (slab foundation 18,000 EUR, photovoltaic system 20,000 EUR) and overall with a 10% buffer. If I can get it somehow down to 1,200/sqm, I would be satisfied, as with solid construction there simply doesn’t seem to be more room to go lower.