ᐅ Single-family house with bay window on the ground floor and first floor – floor plan of the basement?

Hello everyone,

We are currently in the early planning stages of building our single-family home. I have tried out several floor plans so far and came across the following question.
If you build a bay window on the ground floor and first floor, how do you handle the basement (which is planned to be insulated for a separate apartment)?
Do you use the same floor plan as the ground floor, or do you try to keep the basement rectangular and build a slab foundation for the bay window on the ground floor?
Or is it an option to use the outer wall of the bay window and thus have a larger rectangular basement? In that case, I was wondering how the insulation of the basement ceiling would work if it no longer lies beneath the ground floor.

Thanks in advance!

Whether to start a bay window already in the basement becomes less relevant the flatter the site is. In my opinion, a basement larger than the ground floor — even if only partially — is not recommended. Your question could possibly be discussed in more detail with a specific example.

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https://www.instagram.com/11antgmxde/
https://www.linkedin.com/company/bauen-jetzt/

Thank you for your reply. That already helps me a lot!
The plot is almost completely flat. Over a length of about 20m (65 feet), there is approximately a 1m (3 feet) height difference.
I was just wondering whether a rectangular basement is more cost-effective than one with a bay window, or if it doesn’t make much difference.
Attached are two floor plans: one of the basement with a bay window and one of the rectangular basement where the wall cuts off the bay window in the ground floor. In each case, it is the ground floor, and the faintly visible walls are those of the basement.
PS: The length of the house is 13m (43 feet).

Adding a basement underneath a bay window is more complex – bay windows always add extra cost and should have a clear, practical purpose on each floor. What function do the rooms serve (including those in the basement)?
Please present your entire project (including the completed questionnaire, plot details, and so on).

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https://www.instagram.com/11antgmxde/
https://www.linkedin.com/company/bauen-jetzt/

I am working on the floor plans for each level and will post them soon. I appreciate any comments 🙂

What exactly do you mean by the questionnaire?

Goalie31 schrieb:

What exactly do you mean by the questionnaire?

https://www.hausbau-forum.de/threads/leitfaden-zur-hausplanung-auf-dem-Grundstück.30891/

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https://www.instagram.com/11antgmxde/
https://www.linkedin.com/company/bauen-jetzt/