Approximate costs for earth excavation based on soil investigation

This is the soil report for our property. I would now like to roughly estimate the costs for excavation and removal that we will have to expect. Because it will still take a little while until the architect is ready for us to approach the earthworks contractor...
There will be a basement with external dimensions of 8.11m x 12.76m. It should be noted that there is a slope of 1.60m on our property from back to front, and the basement will protrude about one meter out of the ground at the front facing the street (with the 8.11m long side), so that we can have a level terrace at the back...

Can someone roughly tell us how much excavation we should expect and what costs? Many thanks!

This is the soil survey report for our plot.

Really? It reads more like a single borehole in a new development area and not on your specific parcel.

There will be a basement with external dimensions of 8.11m x 12.76m.

The borehole is only 1.5m deep. Either the gentleman didn’t know you planned a basement or my above statement is correct.

I would now like to roughly estimate what costs for excavation and removal we will face

I can’t really say anything about that due to lack of knowledge. I would assume the clay and topsoil have to be removed and disposed of, but others will know that better. However, I believe that because of the insufficient information (only one borehole, missing location of the borehole (you mention a slope), insufficient depth) it will also be difficult for a professional to price this.

Yes indeed, the soil survey was carried out on our property back then and was therefore also given to us by the municipality! And this is now just an excerpt... The whole thing has several more pages...

Yes, imagine that the soil survey was carried out on our property back then and was therefore also given to us by the municipality!

You will need a new one that fits your project. The depth is insufficient, typically one drilling is too few, and the location is vague. A foundation recommendation will be missing from your existing document, as well as the issue of groundwater, waterlogging, etc., which is essential for the construction of the basement (and can mean a five-figure price difference). The good news: as long as the plot is accessible, you can start this order directly. With the result, you will be able to receive very concrete offers from civil engineers regarding the disposal of the excavation material.

For excavation and transport/removal, you can probably calculate between 18-20 € per m³. You can best calculate the size of the pit yourself, but also consider the working space 1m around the house and the slope...

For excavation and transport/disposal you can probably expect between 18-20 € per m³. How big the pit will be, you can best calculate yourself, but keep in mind the 1m working space around the house and the slope...

That cheap? In BaWü you can add another 10 EURO on top and that is the net price.

We have similar external dimensions of the basement. Plus working space, we come to about 450 cubic meters of excavation, but we only have about 30 cm gradient.

As Alex85 already wrote, you need your own soil survey. Costs for this were about 2,500 EURO for us with 7 drillings to about 7 meters depth.

Question, why are you taking care of this? Doesn't your architect handle the tender?