Building on "jelly" - additional measures required

Hello dear ones,

we received the results of our soil surveyor yesterday, which is more than sobering. Our architect described the soil condition as very soft. Direct quote from the architect: "It's like trying to build on jelly."

The soil surveyor recommends the following:

For a frost-proof foundation with a frost-proof foundation cushion with a total thickness of 1.0 m, the foundation base will lie in the layer 2 composed of soft consistency, poorly load-bearing, and compressible silt-fine sand mixtures. This layer requires minor additional measures to safely transfer the occurring building loads to the subsoil. The soft silt-fine sand mixtures encountered at this level are to be stabilized by embedding/pressing in rubble (120/x, 100/200 or similar) until embedding is no longer possible; with a stiff consistency this measure is not necessary.

Does anyone of you have experience with the costs such a measure entails? We have estimated a buffer for the additional foundation costs (approx. €10,000), but our architect brought up yesterday as an alternative a basement. That would probably put us in the cost range of €30,000 - €40,000.

Hopefully it won’t be that expensive, right????

Thanks,
Julia

We also had to replace/dump an average of 1 m. In the end, it was 700 tons of material for about €11,000. It can easily be even more with the basement. If you don't have an expert report done before purchasing the property, you always have to expect additional costs.

Hello there,

Thank you for your response.

€11,000 was without labor costs, right? Oh dear...

Then I will probably have to get various quotes and light a candle in the church, hoping it stays within limits.

We were already aware that we might have additional costs, even without a soil survey. And I am glad to have had the SV done at all. That way we can build the house accordingly so that it doesn't "sink" on us.

I don’t remember exactly. In the end, the bill was 24,000. Because you have to pay for the excavation, luckily we could store it on the property. Disposal would have been even more expensive. However, the price above is completely for all earthworks including the utility shaft and sewer connection.

Building on jelly - I feel sorry for you. But your thread shows that a ground survey is immensely important.

Morning,

well, we had a similar problem. Everything here is marshland.
We are now getting 8 x 16 meter long piles, cost approx. €250,000.

Regards Dirk