Construction ancillary cost estimate average without special items

Hello dear community,

In the past few days, I have been intensively dealing with posts about construction and ancillary costs. It seems that I too have to reconsider my planning and accept the assumption of 3000€/sqm without ancillary costs.

Our budget for the house, including ancillary construction costs, amounts to approximately €400,000 (but a maximum of €450,000).

We plan to have the house built in the "almost finished" stage by a general contractor (GU). We will take over the painting work and laying of floors ourselves or with the help of craft friends.

The house will be built with 1.5 stories, with a maximum permissible built-up area of 86m². It will meet the energy standard of an Efficiency House 40 (KFW eligible), and the equipment can be standard.

The plot is located in the second row and therefore still needs to be developed. In addition, a soil survey and a survey will be carried out (exact costs unknown). Consequently, it is currently difficult to estimate how high the ancillary construction costs will actually be.

Our family consists of five persons, and we aim for a living space of approximately 120m². Accordingly, about €50,000 would remain for ancillary construction costs. Based on my previous reading, I realize that this amount is probably too low, since the costs can quickly rise due to various factors.

I wanted a theoretical example under "normal" conditions. The region is BB.
Should information be missing or the question not answerable at all, I ask for your understanding.

The crux is KfW40 and the development in the second row. For 50m of electricity, water, and sewage connections, you can quickly lay out 20,000-30,000 EUR. For KfW40, you can also easily calculate an additional 100,000 EUR surcharge compared to the minimum requirement under the Building Energy Act.

In your region, a Flair 125 costs from 297,000 EUR. KfW40, a bit of upgrading, and you're quickly at 450,000 EUR just for the house.

Either you forgo KfW40 or you can basically forget it immediately.

Oh yes. Maximum built-up area 86m²? What about paths, parking spaces, terrace, shed for equipment, etc.? And above all... where do you see the budget for all this?

Don't listen to that nonsense. The minimum according to the Building Energy Act is now KfW55, so KfW40 is no longer such a big leap. What it costs you mainly depends on the construction company and their surcharge policy. Because whether you wall up with 36 or 42 stones is no longer a relevant difference in the work. €100,000 definitely belongs to the realm of legends.
Estimating prices is quite difficult right now. The old contracts are slowly being completed, and construction companies have to compete for customers again. Material prices are also slowly decreasing. €400k is not generous but should be feasible for that size. Have you included outdoor facilities in that or are they separate?
I also see a sticking point here regarding development. Depending on the price per meter and length, that can really cost a lot. However, most suppliers have their prices online, so you can easily calculate that yourself.

There is a list of incidental construction costs somewhere here (or search on Google). See which ones apply to you and clarify with the providers which costs are actually incurred. Usually, they have that information on their websites or a phone call helps. Since it is different everywhere, no advice can be given. Water, sewage, electricity can be installed by yourself (meaning just the laying without connecting), which can save a lot of money.

Exterior facilities can usually be done by yourself after the construction, unless it is a slope stabilization.

Is the property and the driveway empty, or is demolition still to be done? Is there room for a 40t construction road? For us, 2 sheds, a garage and a 40sqm garden house had to be removed, that also costs.

I wanted a theoretical example under "normal" conditions. Region is BB.

In principle, the calculation or the factors are very simple for the pure ancillary building costs (without earthworks) Insurance/associations Utilities Surveying Permits Infiltration of rainwater And similar stuff You can inquire about utilities for your district. That involves the driveway, so longer pipeline routes come into play. Surveyors before and also afterwards… usually, you can do without expensive boundary stones. Nine years ago, we paid just under €20,000 including gas in Lower Saxony. Quite cheap with short pipeline routes. I also posted all that individually in the forum back then. I assume it hasn’t doubled, since the expensive connection costs etc. haven’t doubled either.