Regulation on the ancillary cost flat rate of the architect

Hello everyone,

we are currently in the final stages of building our single-family house. We built it with an architect, who was commissioned with service phases 1-8 according to [HOAI 2013 §35, Abs. 1 Gebäude].

Now I have a question about the architect's incidental costs.

At that time, we received an offer from the architect in which all fees were listed according to the service phases. There was nothing about incidental costs in the offer. Now, in the fee invoices, a flat rate for incidental costs of 5% is being charged. According to the architect, these are always applied and do not need to be mentioned in the offer. I can't really believe the architect's statement. Unfortunately, I couldn't find any clear statement on this by googling.

Can you tell me whether incidental costs (as well as their amount) have to be mentioned in the architect's offer or whether 5% can always be applied by the architect.

Thank you in advance and have a nice weekend.

Regards Alfista

I'm glad to have built without an architect

I'm glad I built without an architect

Our architect is quite nice, competent, and fair! that was probably your spell checker :-p

The first architect mentioned the flat rate for additional costs of 5% and wrote it into the offer.

Did the architect not agree to a flat rate, or why are you paying according to the fee regulations? If you do this voluntarily, then you should also have the usual 5%. Because he is allowed to charge you this.

It is already a flat-rate offer or will be billed as such -> Fixed amounts according to the offer, regardless of the actual construction costs. However, suddenly 5% incidental costs are to be added.

The offer itself was made at that time based on the HOAI and the expected construction costs.

Have you given the architect the contract in writing based on the offer, that is, signed the offer without [NBK]?

From my point of view, that would then be binding, and it would be his own fault if he had forgotten the [NBK] beforehand! But as I said, [NBK] are common. Our first architect wanted to charge according to HOAI plus 5% [NBK]. That was then stated in the offer for service phases 1-4, about 12k€.

The architect we then took wanted a flat rate of 4.5k€ for service phases 1-4 and also did very, very good work.