Hello,
Key Data for Desired Build:
Target living space: 150 m²
Plot is on a slope (10%)
- Living basement 2.50 meters (10x9.5) - Garage will be integrated into the basement
- House 1.5 stories (10x8)
Planned costs (partly speculative, partly from neighbors, partly from offers):
Additional construction costs: 33,500 EUR
Shell including heating: 135,000 EUR (basement will be built by ourselves)
Interior finishing: 35,000 EUR
Interior furnishing: 25,000 EUR
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Subtotal: 233,500 EUR
plus cost buffer: 20,000 EUR
Total: 248,500 EUR
First of all, the rough costs if you commission the entire house.
Single-family house, only Energy Saving Ordinance: TEUR 210
Living basement, incl. garage space: TEUR 75
Important: If you want to integrate the garage into the house, higher sound and insulation measures must be taken, as well as installing ventilation for the exhaust gases generated!
Additional construction costs: TEUR 30-40 (with slope rather more)
Painting work in EL: TEUR 12
Floor coverings in EL: TEUR 12
Exterior facilities in EL: TEUR 10
Reserve for extras: TEUR 10
All in, approx. total investment: TEUR 369; probably a bit more in Bavaria, depending on location even more than "a bit."
Much has already been written here about EL; in all cases, you must be sure that family, friends, and acquaintances also fulfill their part of the agreement (help).
My statement (considering muscle mortgage) was of course meant that these prices can only be achieved because planning is done with corresponding labor input. The 1000 hours will also be contributed without significant additional costs (quid pro quo). That is with an average of 3 people on the construction site a total of ~30 Saturdays plus our annual vacation on the construction site, which seems quite realistic to me.
I assume that annual vacation means 24 days. Assuming you work 12 hours daily, you can deduct 288 hours from the estimated 1000 hours. Furthermore, I assume your wife will primarily provide helper services; also important but not notably to be deducted. Remaining – rounded up – are 700 hours, divided among 3 helpers. How long do these helpers stay daily at the construction site – after their actual job? 4 or maybe 5 hours? Assuming 5 hours/day, each of them has 233 hours logged. That means 3 people work 47 consecutive days for 5 hours each on your construction project – will vary in reality as I simply assumed Saturdays as 5-hour working time. Maybe you are at the construction site on Sundays, but the helpers will surely want a rest day? Who organizes the materials to be installed?
Now the other side: a commissioned single-family house with basement of your desired size is usually completed after 7 months. 7 months at 22 working days each mean 154 production days with more/less 8 hours of
professional daily work until handover of the house; plus drying times of the screed, where only EL in terms of wall coverings can be done. All building materials are transported to the site without your involvement.
For professional interior finishing, every provider calculates a good 3 months – with your calculation you want to finish in about 2.5 months – including self-built basement. You can therefore clearly see from the above rough example why users warn you about the pitfalls of EL.
You want to build the basement yourself – why not the entire shell directly? Here – if you trust yourself and have appropriate helpers and "professional" construction management – you can save most euros; less so with interior finishing. In my experience, the inner part rarely comes cheaper because most builders invest the supposed savings in higher-quality materials.
The house will be Energy Saving Ordinance compliant. We decided against KfW. The additional costs for KfW, in my view, do not stand in relation to the supposed monthly savings. It’s probably a matter of belief.
The measures required for KfW 70 are manageable and pay off in the medium term. It is certainly more insulation – the technology installed should be oriented towards the energy loss of the house. Ranges from the 15% rule with gas condensing boiler to heating support up to any kind of heat pump. The advantage – besides heating cost savings per year – is the better resale value.
Rhenish regards