Basis for creditable total construction costs

The questions are also, how big is the house and what is supposed to be done. Renovation costs (including heating, windows, floors, walls) are currently estimated at about €1800-2000/sqm for a normal standard. €150,000 goes quickly, especially with a listed building. As Harakiri already wrote, normal, market-standard construction costs are used for the price estimate. Phases 1-4?

Hello,

the house has a living area of 92 sqm according to the new plan. The architect has now billed exactly for phases 1-4. However, he was not contracted beyond that.

A building application was submitted in the exemption procedure, as there is a development plan. In other words, it was only about exchanging windows, replacing the front door, installing an air conditioner, etc. No structural changes like tearing down walls or recalculating statics.

Also, the monument protection only applies to the exterior shell; interior construction was not mentioned at all in the building application, and he did not plan anything there.

Where does your assumption come from that the €150k would be the assumed construction costs? At the time of the building application (phase 4), exact estimates, especially for building in existing structures, are hardly possible.

Well, we discussed everything with the bank, since for a renovation loan you naturally have to provide a cost statement. We came to about €150,000 there, which is now only a difference of just under €100,000.

If the cost estimates were created by the bank advisory service, they only have a rough relation to reality. The advisors are not architects and do not know the property in detail; as a rule, they are not even able to identify potential cost traps and do not have time to perform a proper quantity survey. They certainly have their experiential values from everyday life, but you cannot seriously compare a gut estimate with an architect's calculation.

If the cost estimates were created by the bank consultants, they only have a rough relation to reality. The consultants are not architects and do not know the object in detail; as a rule, they are not even able to identify potential cost traps and have no time to do a proper quantity survey.

They certainly have their experience from daily practice, but you cannot seriously compare a rough estimate to an architect's calculation.

No, I have independently obtained offers from companies during the 2 months waiting for the architect. And currently, I am arriving at €150,000.

Then you have a basis with which you can start a conversation with the architect.

The architect has now precisely invoiced phases 1-4.

Do you know what the service phases mean? And also that at the latest in service phase 3 a cost estimate according to DIN 276 must be prepared and handed over to you (this is an obligation, not a "wish" from the architect)? You can assume that an invoice according to HOAI without a cost estimate is incomplete and does not have to be paid by you initially.

P.S. You must realize that it was naive to give the architect a blank check. I don’t need to point that out anymore. And as an addition – the renovation of a listed building can easily be calculated at the middle rate (fee zone III) + 30-35% surcharge. Or be directly classified in fee zone IV (or V for very complex renovations).

You know what the service phases mean? And also that by the latest in service phase 3, a cost estimate according to DIN 276 must be prepared and handed over to you

The mutually agreed reality between client and architect regarding the interpretation of "service phase 1-4" in existing building construction often looks like this:
We skip service phase 1, the house is already standing
We skip service phase 2, the house is already standing
Service phase 3 planning
Service phase 4 building application / invoicing.