McGeiwa
2020-02-29 14:03:16
- #1
Hello dear forum community,
we are currently dealing with a new construction planned for this year, 2 full floors, a total of slightly over 160 m² without a basement on a plot of over 650 m². The plot has not yet been purchased. Planning documents were available for a fee. We agreed with the seller to have a soil survey done first.
We know that prefabricated slab buildings stood in the development area in the past, including approximately in the middle of our currently favored plot. During the drilling attempts (small drilling technology), "RC material" (basement filled with construction rubble) was encountered after about 45 cm. They did not go deeper than 45 cm. Now the question arises whether we want to try again with a larger drilling rig (success in getting through not certain) or with excavation pits (where the latter would require hiring a civil engineering company).
According to archive records and the soil expert’s statements, the house would stand approximately half on this filled basement. We have not yet received the expert report. The above-mentioned circumstances are to be understood as an interim report by the commissioned company.
My questions on this:
We have budgeted about €30,000 for the groundworks. However, I suspect a relatively incalculable risk here. We are asking ourselves whether we should call off the purchase.
Thank you very much and best regards
we are currently dealing with a new construction planned for this year, 2 full floors, a total of slightly over 160 m² without a basement on a plot of over 650 m². The plot has not yet been purchased. Planning documents were available for a fee. We agreed with the seller to have a soil survey done first.
We know that prefabricated slab buildings stood in the development area in the past, including approximately in the middle of our currently favored plot. During the drilling attempts (small drilling technology), "RC material" (basement filled with construction rubble) was encountered after about 45 cm. They did not go deeper than 45 cm. Now the question arises whether we want to try again with a larger drilling rig (success in getting through not certain) or with excavation pits (where the latter would require hiring a civil engineering company).
According to archive records and the soil expert’s statements, the house would stand approximately half on this filled basement. We have not yet received the expert report. The above-mentioned circumstances are to be understood as an interim report by the commissioned company.
My questions on this:
[*]Can you build a slab foundation on a basement filled to such a shallow depth (already after 45 cm of drilling)? - Certainly not?
[*]Is it advisable and even possible to build on a filled basement at all? This rubble pit was created around 2006 - 2009.
[*]Would the alternative not be to excavate the entire basement including rubble (if it is only construction rubble disposal costs approx. €35 - 40 per m³, excluding transport costs) and refill it (with appropriate compaction)?
[*]Do you see any further risks?
We have budgeted about €30,000 for the groundworks. However, I suspect a relatively incalculable risk here. We are asking ourselves whether we should call off the purchase.
Thank you very much and best regards