Cost calculation infiltration Drainage application - realistic?

Hello,

we will be building with an architect. The building notification has already been submitted and now a drainage application still needs to be filed. We want to let the water infiltrate on the property. According to the architect, an engineering firm must be commissioned for the drainage application to carry out the calculation of possible infiltration (chamber or trenches). Approximately €1000 is to be estimated just for the planning service of the engineering firm. That seems very expensive to me. Do you have experience with what costs one should expect for the calculation?

Good evening,

The building notification has already been submitted and now a drainage application still needs to be filed.

That is very unusual; in NRW the building application is submitted together with the drainage application.

About €1,000 are to be estimated just for the planning service of the engineering office. That seems very much to me.

€1,000.00 including VAT is about right.

Rhenish greetings

We have submitted a construction notification and not a building application, so the individual drainage application is probably possible. 1000€ for a bit of calculation and reading tables... phew... I still think that's quite a lot. But thanks for your answer.

According to the architect, an engineering firm must be commissioned for the drainage application to carry out the calculation of possible infiltration (shaft or soakaway system).

How should we contradict your architect? But please take your soil survey and ask Graf (or a similar company) for an offer for a suitable infiltration system, for example a soakaway system. That costs nothing, but might take some time.

Edit: The providers of soakaway systems etc. might already be satisfied with just the location since they have a rough idea of the soil.

€ 1,000.00 incl. VAT is about right.

Rhenish greetings

Isn't that a service included in the soil survey? The price seems quite high to me, especially since the whole soil survey already costs less.

Hi,
my neighbors once showed me their calculations for infiltration. Someone had already done a few hours of work, and the results do need to be summarized and nicely presented. But admittedly, I also find 1000 € a bit excessive, that's more than a daily rate...

But to ask differently: why do you want to infiltrate? Do you have to because of the building regulations?
Usually, you can't really save anything with it (stormwater fees).

Best regards,

Andreas