Backwater prevention or house lifting

As far as I have read, it also makes sense to use a lifting device there.

At a channel depth of 2.2m, I don't see the problem at all. There seem to be some local peculiarities here. Maybe ask the planner again what exactly is to be feared.

Just like in the drawing, the volumes of the downpipes soon border on retention basins. In my 30 quiet sleep centimeters, it is already included that the ground slab column comes slightly drunk to work and accidentally lays the house one ground slab thickness too deep.

Just don’t let yourself be sold a pumping station given the conditions as shown in the picture. The shaft can also be a bit deeper. From my point of view, I would !at most! provide an electric backwater valve for the wastewater supply line (<2000€). 11ant has already written everything about it. That would be like suspenders to the belt.

The purpose of raising the house is not apparent from the information. Is there a statement from the association of authorities that there can be an overpressure of more than 3m (0.3 bar) in the wastewater pipe? Very unlikely. A backwater valve certainly does no harm, even if the reason is not clear. Raising the house might make sense if you are building in a flood zone or have groundwater at ground level. Is that the case?

The "reason" behind the whole elevation was, I believe (unfortunately I don't have a drawing of it right now), that there is a relatively steep slope on the street. The drainage in the street had apparently made that necessary. At least the architects had already mentioned during the conversation that the house might need to be "slightly" raised.

According to the construction company, the one meter would probably cost around €15,000...
They estimated a backflow prevention device at about €4,000-5,000. But I don’t know right now whether they included a lifting system in that.

OK thanks, now I have a basic idea. We will really decide against the elevation.
However, I am still interested in how much the maintenance costs.
I have read that, for a single-family house, maintenance should be done once a year. I found very different prices. But that surely also depends on the specific technology and the manufacturer. On average, I saw prices of €150-200. Is that realistic?