Area for storage of excavated material? Without official approval?

Hello everyone,

we are planning a house approximately 11.5m x 9m with a basement. The plot itself is very flat, so you can probably expect about 11.5m x 9m x 3x = 310 m^3 of excavation.

Our soil disposal site charges 28€ per ton, so that adds up quite a bit. However, there is a larger project planned nearby that requires about 10,000 m^3 of soil. I could give the excavation away there for free. Now it will take 1-2 years until the soil can be dumped there, so I would like to store the excavation at the neighbor’s place. The neighbor’s property is also a building plot, but it was already developed in the 1980s and has not been built on so far, and the current owners also do not plan to build there soon. The reason for storing it at the neighbor’s is simply that I can start with the garden immediately after building the house and don’t have to wait until the soil is gone.

However, I find it hard to imagine how much space is needed. I still need to ask the neighbors and wanted to know roughly how large the occupied area is. Can someone tell me if the yellow area is enough to store the soil from the red area? Is there anything to consider here? I’ve heard something about an "immissionsschutzrechtliche Genehmigung" starting at 100t. But I understand that you do not need this if the excavation was done immediately adjacent. Does this also apply to the neighbor’s property or only to one’s own?

Thank you very much!

I can’t imagine that the neighbor will agree. But if he does, I would be very surprised if anyone else cares.

If you build a basement measuring 11.5x9m, you can easily calculate the excavation to be about 15x13m. And not all of the excess dug out will be filled back into the pit because of drainage and so on. That will be 500m³.

The neighbor will probably laugh briefly and then refuse. How should he know that in 2 years you'll even have the money to remove that stuff? Because you'll presumably pay for the trucks to the construction site.

And what are they supposed to do with 10,000m³ there, most of which is probably not usable for the foundation? And what if someone next door tells your driver, "Sorry boss, we don't need any more..."

And last but not least... does Intel mean anything to you? They also wanted to build big and a few months before the planned start it was put on hold, probably forever.

PS:
And as always in life. Nobody cares until someone screws you over.

Purely in terms of volume, you should roughly calculate around 300–500 m³, depending on the depth of the cellar and the construction method. If you want to pile up the excavated material 2 m high, you will need about 150–250 m² of area – this corresponds, for example, to an area of 15 × 10 m or more, depending on compaction and the type of material.

Important point: Such earth mounds are considered "waste storage" depending on quantity and duration – and from 100 t (which, for clayey soil, is already about ~60 m³) you are theoretically subject to notification or even approval requirements. That it is "directly adjacent" only applies to your own building plot, not to the neighbor's meadow.

Conclusion: Yes, technically it is possible – but you need a clear, written agreement with the neighbor and should also briefly consult the municipality or the district office. A phone call is enough, so you don’t get into trouble later. Otherwise, it can get really expensive if someone files a complaint.

And honestly: In practice, something like this rarely works smoothly over years.

so that one can presumably calculate about 11.5m x 9m x 3x = 310 m^3 of excavation.

I come to over 500 cubic meters of natural soil as excavation (basement excavation must be larger than the basement, you calculate about 1.50/2 meters extra on each side) Natural soil in excavation is about 3 times as much in cubic meters because the soil is loosened. That means at least 1500, so nearly 2000 cubic meters.

But there is a larger project planned near us, which requires about 10,000 m^3 of soil.

I could give away the excavation there for free.

That’s what you say. And who pays for the trips for soil excavation that is covered with weeds? It almost only works in theory. But ultimately you have nothing to lose, whether to dispose of the excavation now or in two years – it’s worth a try. However, I believe the earthworks company will handle it more competently and cost-effectively. You can calculate for yourself how often a vehicle must drive to remove about 1500-2000 cubic meters (1.5 cubic meters of soil is supposed to weigh about one ton). And how much time it takes to load a truck. And one should keep in mind that soil is not compressed in cube form. We have ourselves given away our soil via classifieds. On one Saturday, only a fraction of what we had to store on the property (floor slab construction) was removed. The beneficiary gave up after about 10 trips, and we had to find another way to dispose of it.

Depending on the soil type, 20 to 30% is added from in-situ to loosened soil.