Is soil investigation necessary?

What comes to my mind about this is that all the houses built 20, 30, 40 years ago, before it became fashionable to drill a hole every 5 meters, have not all collapsed on themselves.

No one is claiming that either. But just look at the facades for example – there have been 3 earthquakes in our region over the last 30 years. Or ask the people how their basements look...

That risk would clearly be too high for me.

Rhenish regards

The report helps you and your general contractor to estimate the founding costs. For example, at our place there is solid rock at one corner of the house, while on the other side we have 2m deep foundations. At the neighbor's 20m away, it looked completely different again.

Can you explain to me the difference between "Bohrungen" and "Rammkernsondierungen"?

I'm not really a geologist, and "Bohrung" was also misspelled.

Our services were as follows:

[*]Two dynamic core soundings according to DIN 4021 up to 6m for analyzing the layers of the subsoil
[*]Two heavy dynamic soundings according to DIN 4094 up to 6m to test the load-bearing capacity. In this process, weights are used to check how much the soil yields under a certain load to prove the load-bearing capacity.
[*]Surveying of the drilling points and sampling.

The report according to DIN 4020 and 4022 then had 25 pages and included:

[*]Cross-section of the ground
[*]Location plan of the drilling points
[*]Layer index
[*]Soil classes according to DIN 18 300

[*]Specification of groundwater or layer water levels
[*]Determination of soil parameters according to DIN 1055
[*]Assessment of load-bearing capacity according to DIN 1054
[*]Foundation recommendations
[*]Frost impact classes
[*]Specification of special measures (soil replacement, foundation deepening)
[*]Specification of soil characteristic values
[*]Information on protection against water, waterlogging, soil moisture according to DIN 4095/DIN 18195
[*]Information for excavation creation, building waterproofing
[*]Information on possible reuse of excavated soil
[*]Information on any existing contamination of the subsoil
[*]Information on possible infiltration
[*]Information on earthquake zone
[*]Information on unexploded ordnance

That’s the summary from the offer. According to our general contractor, this was one of the better reports they have received. I also saw our neighbor’s report: 2 pages, summarized in bullet points ...

According to our general contractor, that was one of the better expert reports they have received. I also saw our neighbor's: 2 pages, summarized in bullet points ...

That is the classic case of well-invested money versus saving in the wrong place

Rhenish greetings

This is the classic case of well-invested money versus saving in the wrong place

The neighbor's expert report was carried out by the GÜ, they did not commission it themselves, so it is of less interest to them, since the liability should be clear (?). But it saved us a lot of money because without the geologist we would have had to slope according to the development plan, which would have led to shoring, so costs in the five-figure range. The authority also temporarily shut down four construction sites because of this...

I'm not really a geologist, and "Bohrung" was also misspelled .

Our services were as follows:

[*]Two driven core soundings according to DIN 4021 up to 6m for analyzing the layers of the subsoil
[*]Two heavy driven soundings according to DIN 4094 up to 6m, to test the load-bearing capacity. In this process, weights are used to check how much the soil yields under a certain load, in order to prove the load-bearing capacity.
[*]Surveying of the drilling points and sampling.

Thank you for the information. We have now requested an offer from 5 geologists. The first offer we have already received, with the same content as yours. The offer amount is approximately €800 gross. This has settled the consideration for us regarding a commission.

We will, most likely, commission this geologist, as the offer description as well as the homepage and the contact were very friendly & good.