Construction costs single-family house offer realistic?

Hello everyone,

I would like to ask you for a rough estimate regarding the construction costs offered to us for our single-family house.

Here are just the basic details about the house:

- Location: approx. 60km from Stuttgart
- Living area approx. 160m2 + basement
- KFW 55 EE (with air-to-water heat pump and photovoltaics) without ventilation system
- Equipment I would consider standard.
- Without garage and outdoor facilities
- Solid construction (aerated concrete)
- No dormers (but almost exclusively floor-to-ceiling windows)
- Floor + painter not included
- 1 lift-and-slide element
- 1 basement room including underfloor heating
- Standard roller shutters without electric

The offer price is approx. €450,000 without ancillary construction costs and land

Do you consider this reasonable?

The offer includes €13,000 for KFW 55 and another €13,000 for a photovoltaic system to achieve the KFW 55 EE standard
Question about this:
Why do I need a photovoltaic system for the EE class? Isn't the heat pump sufficient to draw 55% of energy from renewable sources?

I would appreciate some feedback.

Best regards

Too few details. But at first glance sounds somewhat realistic with €2,800 / sqm. How exactly is the basement constructed? Watertight concrete? Only 160 sqm in ground floor/upper floor? Roller shutters with strap? Who is the offer from?

Photovoltaics are not required for KFW 55 EE, but very sensible! Why no controlled residential ventilation?

It seems very affordable to me. If you subtract the basement, which even has 1 heated room, then there are roughly only 2200€/sqm left. I wouldn't have thought that you can build for that in the Stuttgart area.

60 km as the crow flies is definitely no longer the Stuttgart area. However, details are missing, including about the location.

Roller shutters with a strap? My energy consultant said that is not possible in a KfW house. Quote: "All thermal bridges" :)

Quite realistic!

160 m² + basement (even WU-basement) with garage and ventilation system, without photovoltaic system with very decent equipment we currently pay 450k – but of course here still at last year’s old conditions – so no idea how much the actual surcharge is. We are also building 60km from Stuttgart – so I can definitely give you a realistic regional assessment.

If I price my ventilation system equal to your photovoltaic system, but then deduct the garage – I would be at 425k.

We even have floors included.

Basically, that is very cheap even for the current situation!!

Roller shutters with strap? My energy consultant said that’s not possible in a KfW house.
Quote: "All cold bridges" :)

Then your energy consultant is talking complete nonsense :D