Cost issue for earthworks on a slope

Hello dear house builders,

like many here, I am also currently in the house planning phase. I am really still at the very beginning, meaning the plot of land is reserved, there have been talks with construction companies, and a table of all additional construction costs has been created, also with the help of many posts I found here in the forum. However, there is one gut-wrenching item: earthworks. The plot slopes down about 1.5-2 meters on the side over the entire width (20 meters). I have read a lot in the past few days and I am currently very unsure about what costs for earthworks might come my way. At the moment, I have a range of 20,000 - 100,000 €, and I currently cannot calculate/plan with that. In the last conversation with a construction company, the salesperson told me that my current inquiries to civil engineering firms cannot provide a proper offer because I lack soil surveys and so on. But I can only provide all required information if I buy the plot, a catch-22. So I’m just trying my luck here in the forum; maybe someone of you had a similar plot and built on it and can give me a rough cost estimate or what items come in addition to a level plot. Yes, I know it is relatively difficult without knowing the soil, but maybe the current range of 20,000-100,000 € can be narrowed down a bit. I’m attaching a picture, exactly from the front. By the way, the planned house has a width of 9.50 and a depth of 11.50 meters, and the plot starts directly to the left in the picture. I look forward to any helpful, constructive contributions.

The question is: What do you want to do approximately? Bury yourself into the slope (build a basement level)? Or fill everything up so that you lie 2 meters above the street, for that matter? How do you imagine the driveway situation?

Best to make a (hand) sketch of how you imagine your house, garage/carport & driveway, and maybe one can say more precisely.

1-2 m is quite inaccurate. that is a 5-10% slope. at 10%, a basement can already be worthwhile. there is surely a geoportal in Hesse as well. you can definitely find some information about the property there. a plan of the property with possible elevation details and the development plan are quite helpful. regarding the geology, I would first ask the neighbors if there are any special features.

Hi,

or maybe ask "your new neighbors"? They should know the soil conditions quite well. Their houses must have been standing there for quite some time.

As Hanghaus2003 has already written, looking into the Geoportal helps to see what could come below.

My remote diagnosis of the property:
If you look at the mountains in the background, I assume that solid rock comes relatively quickly.

Some topsoil, then slope clay (based on morphology no more than 1-3 m), then solid rock. Groundwater is probably not present, of course after precipitation inflow on the slope side must be planned.
However, the report will show the exact details; from my experience, I think there won’t be any major problems here.

What can happen is that the rock appears too early and the earthworks contractor has to "chisel" into the soil.
What it then depends on, as already mentioned, is how the house is built (basement/slab) and how it is positioned. To optimize costs, these adjustment points can be used after the report.

The price depends on many factors.
-regional differences
-how much material must be removed
-how much must be refilled
-which material is used for refilling...

In the last conversation with a construction company, the salesperson told me that my current inquiries with civil engineering companies could not provide me with a proper offer at the moment because I am missing soil reports, etc. However, I can only deliver all the required information if I buy the property, a catch-22.

Well, one could also create a soil survey if one were allowed to commission it before the purchase. Just ask. I don’t see the property now as something where you can simply say, this and that house should be placed there and the rest has to be compensated. A house and land are, after all, 3D, and that also means planning with the slope instead of just putting a BoPl house flat on it. Because then expensive features arise, such as a staircase landing to the entrance, steps in the garden, or to the garage. We paid €20,000 twelve years ago for a flat plot for the slab. I would first make a cross-section of the plot and then look at how things will be with the heights and the house: where something needs to be excavated, where something needs to be added, where the earth can be distributed, how many cubic meters must be removed. Rebuild the slope with Lego and try to get a simple house and a garage to fit on it straight. The earth particles can then be calculated. But be careful: existing topsoil has only about 1/3 of the volume of the later pile that needs to be disposed of.