New construction - questions upon questions...

350k with or without land?

Without! We already have the [Grundstück].

You will save above all here:

- On the size
- On the basement
- On the dormer
- On the technology, as you already wrote yourself

160 sqm + basement, that is already bigger, but of course I do not know the background. Maybe 160 sqm without basement or less sqm with basement is enough. It is also a question of the floor plan.

Dormers can often be saved depending on the floor plan.

Hello,

We are planning a new build for the two of us and our (planned in the near future) family (in NRW rural area).

"Ostholland"? :D

First of all, we were shocked by the price level for building, but apparently others feel the same... We are currently figuring out where savings (usually through own work) can be made.
A few details about the planned house:
- Ground area approx. 9.50 x 12 m / living area approx. 160 m²
- including basement (initially not finished)
- 1.5 floors (knee wall 1 m, roof pitch approx. 40°)

That would be roughly 185/190 sqm living area and would cost around EUR 315,000 turnkey as a KfW 70 efficiency house with usable basement.

1.) The developer, whom we currently lean towards, would charge about 165,000 euros for the shell including roof (one dormer) and plumbing work (single-layer with 36.5 cm brick). Is this price okay?

Without windows and exterior plaster okay – if these trades are included in the price, I would be cautious.

2.) For the roof and plumbing work about 28,000 euros are budgeted (included in the above price).[...] Would it be worth taking the roof out of the overall offer and doing it as own work?

What does your current favorite think about this idea? And who would take over the warranty on own work?

3.) So the question remains: heat pump or gas? What do you say about acquisition costs and annual costs for electricity/gas? Who has experience here?

This question has been discussed here many times; I alone have answered it - felt like 100 times or more. Read up a bit here, then you will find answers.

4.) On the other hand, it is always said that today’s well-insulated houses should definitely be built with ventilation systems (with heat recovery) (mold, etc.). What does the community think here?

See above. With purely monolithic masonry it just barely works without ventilation. Have you ever thought about a decentralized system? For KfW 70 you will in my opinion have to favour some technology anyway :-)

5.) Overall, based on the offers, we have calculated a total price (excluding outdoor area and garage) of approx. 350,000 (already adjusted for planned own work like painting, laying laminate, etc.). Not exactly a bargain for a (presumably) KfW 70 house. Is this okay in your opinion? Just from your feeling. I know it depends on so many aspects... All in standard quality, but with electric shutters.

Not exactly a small house.

You should answer the question yourself whether you want quality or just a house with four walls? Does it have to be around 190 sqm living area and is the basement absolutely necessary...

House KfW 70 including usable basement - EUR 315,000
Painting work as own work - EUR 10,000
Floor work as own work - EUR 10,000
Outdoor facilities as own work - EUR 10,000
Additional building costs - EUR 35,000-40,000
Reserve for extras - EUR 10,000

All in an investment - without garage - of EUR 395,000 and then there better be no surprises lurking in the ground!

PS: I overlooked the dormer, depending on size it adds a further EUR 4,000 and up.

Rhenish regards

2.) Approximately 28,000 euros are budgeted for the roof and the plumbing metalwork (included in the above-mentioned price). I might possibly have someone on hand who could do the roof with me as a self-performed task. He said you can roughly calculate 200 euros/m² of roof area (everything included, including insulation), if you have a company do it. What do you think about this estimate? Realistic? Would it be worthwhile to take the roof out of the overall offer and do it yourself?

I am always cautious about self-performed work. Is this someone a professional? Then he will probably work regular hours during the week (like you) and most likely will not fill his vacation with work. That would mean he could only possibly work in the evenings or on weekends. And that also with your help as an unskilled worker.

That will take its time, during which you will continue paying rent and possibly already interest on your loan. Usually, it doesn’t get much cheaper than having it done because it simply goes faster.

Then there is also the warranty. Especially with the roof (or the entire exterior shell), I would personally prefer that it is really done professionally.

That would really be worth considering.

350,000 euros without land seems very much to me. We are building a 200 sqm house without a basement, but with a garage, and we are calculating with 250,000 euros. However, we do a lot ourselves, also in the shell construction. And we do the site management ourselves, which means we award all trades ourselves. You can save a lot that way too. Of course, it takes a lot of time. We also thought for a long time about whether gas or heat pump, but we decided on the heat pump. No one can tell you what pays off more, since no one knows how prices will develop. It is a matter of conviction. In my opinion, if you are skilled in crafts, you should do as much as possible yourself. You can really save a lot of money that way. Regarding the warranty, you would of course have to clarify that with the builder. We decided against a ventilation system. As you already say, it is expensive to purchase. And the maintenance and servicing also costs money. In addition, mold can also form in the pipes. I prefer to ventilate often enough by opening windows, then there is no mold.