ᐅ Basement Compaction / House Demolition

Good evening,

I own a plot of land with a house that is ready for demolition and a damp basement (at times, groundwater seeps into the basement). I am now planning to demolish the house and fill in/compact the basement in order to build a new house on the existing footprint.
The basement is about 1 meter (3 feet) deep underground (raised basement).

Now my questions:
1.) Does the basement need to be completely removed, or can the walls and floor remain in the ground?
2.) Is it advisable to build on the old footprint at all, or could the new house settle unevenly?

Thank you in advance for your answers!

Best regards,
Lena

Hello Lena,

Lena schrieb:
Now my questions: 1.) Does the basement have to be completely demolished, or can the walls and floor remain in the ground? 2.) Is it advisable to build on the old foundation plan at all, or could the new house settle?

No one here can provide you with a verifiable answer to this. To get satisfactory responses to your questions, you should first consult a demolition contractor who can assess the existing building structure. Then, a geotechnical engineer or soil expert should be consulted, who can give you a reliable evaluation of the soil conditions based on borehole investigations.

Best regards

Hello Lena,
I can only agree with Bauexperte. An objective assessment by professionals never hurts, and in your specific case, it is especially important.

A few general notes:
Building on an existing basement is, in my opinion, challenging. After all, it is safe to assume that you do not want to rebuild the same house, and the existing load-bearing elements can only be used to a limited extent. This would result in varying load-bearing capacities for the new building. Furthermore, it is uncertain whether and for how long the load transfer through the remaining basement walls, foundations, etc., will remain reliable.

I would recommend completely demolishing the basement, then having the soil tested by a geotechnical engineer (around 500€), and subsequently backfilling with suitable load-bearing material to construct the new building.

If you need further information or have any questions, feel free to contact me...

Best regards,
w - bpb

Hello, I have a similar project planned. I have a plot of land with an old house (4.5 x 8.5 m (15 x 28 ft)) and next to it a basement (1 m x 2 m (3 ft x 6.5 ft)) with external access. I want to demolish the entire building and rebuild it in about 5 years. What should I do with the basement? Do the walls need to be completely removed down to the foundation slab, or is it sufficient to remove the walls starting 1 m (3 ft) above ground level and then backfill the rest? What type of soil is needed for this? Gravel and regular fill soil?

Best regards,
ronnystritzke