ᐅ Removing a Basement or Filling It In?

Is reusing the old basement for the new construction not an option?

Hello.

Although I am not an expert in construction, I find it hard to imagine that simply filling in the existing basement and then building a new slab on top would work.

The entire "fill material" would most likely need to be properly compacted to ensure sufficient stability when the new building is constructed (unless you completely fill the basement with concrete...).

In addition, wastewater, fresh water, and possibly drainage pipes need to be installed somewhere. How would that work in this case?

I would either consider Masipulami’s idea or, as an alternative, completely demolish the basement, fill and compact the space, and then build on it.

It’s actually a shame to fill in an already existing hole. That probably won’t be cheap either—I would get quotes for this work and then compare it to the cost of building a new basement, since the excavation is already done...

Best regards,

Dirk

Thanks for the responses. A basement is not an option for us due to moisture concerns. Now the question is whether to include the intermediate floor in the "hole" and keep all the walls standing, or only remove them partially, or if we should excavate everything. Cost: demolition and backfilling max. 3-4 k€ and a lot of work.

Hello Majohr,
simply throwing the intermediate floor into the hole could cause issues related to illegal waste disposal. To create a proper foundation, there will be no choice but to completely demolish the basement and fill the resulting excavation with compactable material, compacted in layers.
The argument against having a basement should not be moisture, as that can be managed. Rather, the costs involved if you decide to forgo a basement are the main consideration.
However, you should carefully think over this decision, as it might truly be a significant sacrifice!

Hello Dirk,

Majohr schrieb:

We bought an old bungalow with a basement. The upper floor is almost completely demolished.
Now our question is whether we can simply fill in the basement during the new construction or if we need to completely remove the basement and refill the area? A new house without a basement is planned to be built on this plot.

It depends ....

We have construction sites where the demolition material can be reused for building up and others where this material is completely unsuitable. Talk to your geologist and civil engineer; if the old basement material can be used, the most cost-effective solution is to compact the basement void.

Either way - completely demolish and then found and compact according to the requirements of the geological report.

Regards, Bauexperte

Are the basement walls of the new building project structurally sound? Are the old foundations sufficient to support the new load? In any case, the damp walls could have lost their strength and thus their load-bearing capacity over the years.