Extension and Renovation: Architect Fees Phase 1-4

Hello everyone,
We have bought a house from 1921 (110 sqm living space) and want to add a floor (approx. 55 sqm) and renovate the house (preferably with KfW 261, if still available).
We have meanwhile found an architect who would make a rough preliminary planning for the building inquiry for the extension and then draw the building plans (phases 1-4). The energy consulting will be taken over by someone else.
The fee calculation according to HOAI is clear to me so far. We had overall set a budget of up to 450,000€ for the extension (approx. 250,000€) and renovation (approx. 200,000€).
Now, however, the architect has assumed 450,000€ as the construction sum to calculate his fees and is thus already over 20,000€ for phases 1-4.
Is that correct?
I had calculated a lower amount of total eligible costs with 250,000€ gross for the extension.
Thank you very much for your time and help!

The eligible construction costs according to the HOAI are the net construction costs (excluding VAT) of the commissioned cost groups (KG) 200/300/400, possibly also KG 500 (external facilities). The fee calculation also includes the specification of the fee zone, the fee rate (range), then for your construction project the reconstruction surcharges of 20-33%, the incidental costs and the VAT.

The architect's fee is counted towards KG 700 (ancillary construction costs). If these were also included in the €450,000 you mentioned, they must also be deducted, as they do not count as eligible construction costs. KG 700 also includes other fees (surveyor, soil expert, structural engineer, TGA engineering services, etc.) which would also have to be deducted.

Your commissioned architect should provide you with a detailed and comprehensive presentation of the above-mentioned fee parameters underlying his fee calculation. He is also obliged to do so according to the HOAI. Apart from that, what is decisive are the agreements you have made with him in the contract for work/architect contract.

Thank you very much for your detailed response!

So it is correct that the architect calculates his fee for the construction plans of the [Aufstockung] also based on the renovation costs of the existing building?
If we were to only add the [Aufstockung], without renovating the existing building, the architect would receive about €8000 less for the same service?

The architect is paid according to the eligible construction costs of the planning services he has provided - no more, but also no less. He must present these services to you in detail.

The eligible construction costs referred to in his fee calculation must have been plausibly calculated either in the form of a cost estimate (according to [Lph 2/Vorentwurf]) or a cost calculation (according to [Lph 3/Entwurf]) or based on already available tenders for contracted construction services. Anything else is not acceptable.

We bought a house from 1921 (110 sqm living space) and want to add a floor (approx. 55 sqm) and renovate the house

Describe the type of construction: is it a "one-and-a-half-story" house with 70/75 sqm ground floor and a converted gable roof without knee wall?

We have meanwhile found an architect who would do a rough preliminary design for the building inquiry for the extension and then draw the construction plans (phases 1-4). The energy consulting will be done by someone else.

You don’t need just any architect, but specifically one experienced in building renovation. And phase 5 is especially important; you always pay for it (either as a planning fee or as a tuition fee for improvisation). Taking a "rubber-stamper" to satisfy the law and awarding construction contracts without tendering would be naively reckless.

So if we only add a floor without renovating the existing building, would the architect receive about €8,000 less for the same service?

That would not be the same service; there would be significantly less to plan.

The HOAI is no longer binding - just negotiate a fee with your architect.
GD