Construction costs for a single-family house with a basement in NRW

Well,

5k wood fireplace
10k geothermal
0k flat roof

So in MG-Land (Rheindahlen) houses are currently being sold by a developer.

314,000 EUR, semi-detached house, 122 sqm living space, 290 sqm plot, without garage, without basement, no special energy standard, air-to-water heat pump, gable roof....

Therefore, I cannot and do not want to believe 190. Unfortunately, I am still on the road. But it doesn't help anyway.

Calculate at least 1,500 euros per sqm, rather 1,800 euros. + basement + incidental construction costs + extras.

The 190 were also from 1.5 years ago. But even the current prices are very far off. After all, here they are talking about at least 400k just for the house. If you assume your 1,500€ I am at 150 sqm with 225,000. Plus basement + incidental construction costs + extras. That would then be 175k for basement and incidental construction costs and extras. No special energy standard is also highly questionable, because the difference between the energy saving ordinance and KfW55 is only 10 kWh/sqm per year. With that, you might save about 70 euros per year on a gas heating system.

.... therefore many also forego the cost factor [Keller]

.... that is why many also forego the cost factor of a basement

Yes, but how high can the surcharge for a residential/utility basement be? Surely not 80k? Considering the prices that are coming up here, I'm slowly starting to wonder if anyone is still building at all.

Well, we have actually been wondering about that for a while. We don't earn badly, but we definitely don't consider ourselves "rich." Once we've paid all the bills, I will make a list of what the basic costs were and what counts as luxury, let's see how it looks then.. If you can even clearly separate everything like that... We are building without a basement, we would also need a waterproof concrete shell [weiße Wanne], and we had no desire for the extra costs or for climbing stairs.

Surely not 80k?

Right, it’s more. But it depends on what you really mean by residential basement. If you take it literally, i.e. equally equipped as above-ground living space, it will cost about the same per sqm as the above-ground living area, plus additional effort because it’s more expensive "downwards" (earthworks). That’s the most expensive variant. If you omit skylights, (full) bathroom and the like in the "residential basement" and a ceiling height of 2.40m is enough for you, you’ll be closer to 80k€. It will at least have screed, be within the heated envelope, electrical installation flush-mounted. Pure utility basement as a "white tank" certainly 45-50k€.

Or thought about differently: If you have two floors and have to pay 300k€ for that, why do you think a third floor would be built at a fraction of the previous costs? Going downwards is the most expensive thing you can do (of course, the 300k€ only include one-time costs such as connections etc.). But maybe this approach makes it somewhat more understandable.

At the prices coming together here, I’m slowly wondering if anyone still builds at all.

Nope. You can build significantly cheaper. You just have to realize here that your wishes don’t fit the budget. Because these are by no means standard. You’re describing a fairly large house (the biggest cost driver by far) with a large technology package. Only 3-5% build like this.

I’ll give you a rough comparison with our project, also NRW. We’re at about 2200€ per sqm, KFW 55, geothermal heat, central ventilation, photovoltaics. But including ancillary construction costs. For your 150sqm that would be 330k€. 50k€ utility basement. 25k€ double garage (prefab can be somewhat cheaper, masonry over 30k€), 20k€ garden (the bare minimum), 15k€ kitchen. That’s 440k€. Plus further furnishing like lamps, mailbox and all the little things. Move, double rent, possibly financing costs (commitment interest etc.).

True, it is more. But it depends on what you really mean by a living basement. If you take it literally, that is, equally equipped like above-ground living space, it will cost about the same per square meter as the above-ground living area, plus additional costs because it is more expensive "downwards" (earthworks). This is the most expensive variant. If you forgo skylights, (full) bathroom, and the like in the "living basement" and a ceiling height of 2.40m is enough for you, you can manage with the 80K€. It then still has screed, lies within the heated shell, electrical installation flush-mounted. Pure utility basement as a white tank surely 45-50K€.

Or thought the other way around: If you have two floors and have to pay 300K€ for them, why do you think that a third floor could be built for a fraction of the previous costs? Downwards is the most expensive thing you can do (of course, the 300K€ only includes one-time costs like hookups, etc.). But maybe this approach makes it a bit more comprehensible.

Since a basement is neither clad with bricks, requires less insulation, has no windows but light wells, and is even half unheated, the price should be lower. After all, you are not building an equivalent floor and then burying a brick façade, right?

Nope. You can build significantly cheaper. You just have to realize that your wishes don’t match the budget. Because these are by no means run-of-the-mill. You’re describing quite a large house (the biggest cost driver by far) with a large technical package. Only 3-5% build that.

I’ll give you a rough comparison with our project, also NRW. We are around 2200€ per sqm, KFW 55, geothermal, central ventilation, photovoltaics. But including incidental building costs. For your 150 sqm that would be 330K€. 50K€ utility basement. 25K€ double garage (prefab can be somewhat cheaper, masonry over 30K€), 20K€ garden (the essentials), 15K€ kitchen. That adds up to 440K€. Plus further furnishings like lamps, mailbox, and all the small stuff. Moving, double rent, possible financing costs (commitment interest etc.).

KFW 55, geothermal, central ventilation, photovoltaics. except for the ventilation, has nothing to do with the house I described.

Just to remind you. 1.5 floors 150 sqm, living/utility basement double garage brick façade central ventilation with heat recovery underfloor heating gas condensing boiler + solar or air-water heat pump electric shutters