ᐅ Pile foundation in boundary construction

The soil survey revealed that a deep foundation with piles is necessary because stable soil starts only at a depth of 8 meters (26 feet). Since the lot is narrow, the carport with a storage shed will be built along the property line with the neighbor, extending 9 meters (30 feet) in length. Three piles would need to be installed there, which could potentially affect the neighbor’s house. The foundation company suggested an alternative pile foundation where the piles are essentially "screwed" into the ground. This method would avoid vibrations for the neighbor but would cost us almost twice as much. Has anyone had experience with this?

You have basically summarized it well yourself. These are the two options and their financial implications. Please carry out a condition survey before starting construction and document the neighboring building’s condition to be prepared for any future disputes.

And then we pay for the damages to the neighboring houses, not the builder's liability insurance.

I believe your problem is that you have never seen something like this in real life; otherwise, you wouldn’t seriously consider that option.

Yes, we have experience with pile foundations. We used micropiles that were drilled into the ground. It cost quite a bit more (we built a bungalow, so a larger floor area), but we knew the costs before purchasing the land. We are also very satisfied with the company that carried out the work.

Regarding protection measures for the neighbor, I unfortunately cannot comment, as this was not necessary in our case. Please note that the foundation slab may also need to be reinforced accordingly.

We have now received a cost estimate for bored piles. 19 pieces, each approximately 13 to 14.5 meters (43 to 48 feet) long. The total cost is supposed to be €47,000. Is that normal?