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FAQ – For your information

What is the HOAI?

The German Fee Scale for Architects and Engineers (HOAI) is a federal ordinance that regulates the remuneration of architectural and engineering services in Germany.

The HOAI aims to guarantee the architects and engineers sufficient remuneration and to guarantee clients quality planning, tendering, contracts and site supervision. Competitiveness should be solely based the quality of work, not the price.

Most architectural and engineering tasks are categorised according to HOAI into nine service phases. 

What is a BImSchG application?

BImSchG is the German Federal Immission Control Act.

The purpose of this act is to protect people and plants, the soil, the water and the atmosphere as well as cultural and other material goods from harmful environmental effects, and to prevent such harmful effects from developing.

A permit is required for facilities capable of causing a negative environmental impact, or that are otherwise hazardous or detrimental to the public or the facilities’ surroundings. These facilities are listed in the Annex of the Ordinance on Installations Requiring a Permit (section 4 of BImSchV).


This permit is to be issued by the authorities after ensuring that the construction and operation of the facility meet high environmental protection standards

  • which prevent negative impacts on the environment and other hazards that have adverse effects on the public and the facility’s surroundings;
  • precautions are taken against negative environmental impacts or other hazards and adverse effects, especially by using the latest technological measures;
  • waste is avoided, unavoidable waste is reused and unusable waste is eliminated without negatively affecting the public good; waste does not need to be avoided if, based on the latest current technology, it is impossible or it cannot be reasonably expected to be avoided; waste avoidance is impractical because it is more hazardous to the environment than reuse; waste is disposed of or reused according to the specifications put forth by the Closed Substance Cycle Waste Management Act and other specifications regarding waste;
  • energy is used economically and efficiently.

What is a general contractor (GC)?*

A general contractor is hired to carry out all construction services and is authorised to use third-party companies (subcontractors) for some or all of these services. However, there is only a contractual relationship between the client and the general contractor, not between the client and the subcontractor. A general contractor is therefore a contractor to the client, but a client to the subcontractor. In a general contractor contract, general contractors perform a large amount of the work themselves.


Despite being authorised to hire subcontractors, the general contractor is still responsible to the client and must construct the building as agreed. The general contractor is responsible for any defects that may occur. 

What is a construction manager (CM)?*

A construction management contract is similar to a general contractor contract; however, construction managers do not provide construction services themselves.


People wanting to build often hire general contractors/construction managers under the assumption that they will take care of everything. These companies are often hired for planning and also the construction itself. They are even granted the right to hire subcontractors. A tradesperson who is associated with the general contractor often acts as the site manager. In this situation, you need to ask yourself who represents your interests in dealings with the general contractor. Who advises you independently with respect to the general contractors’ recommendations? 

What is an architect?*

Generally speaking, if the construction is supervised by an architect, more serious mistakes in construction can be avoided. If you use an architect’s full range of services for a project, these will include the design of the building, the tendering out services, the supervision of construction and the examining buildings for defects within the warranty period after the project has been completed. Of course, such comprehensive architectural services come at a price.


You must decide if you want to invest your money in a relatively safe way of constructing of your building. You will also enter into a contract with the architect. The German Fee Scale for Architects and Engineers (HOAI) consists of nine service phases:

  1. Preliminary assessment
  2. Preliminary design planning
  3. Design planning
  4. Planning for permit applications
  5. Construction planning
  6. Preparation of tenders
  7. Assistance in tenders
  8. Site supervision
  9. Property maintenance and documentation

These constitute comprehensive architectural services. You may also choose to commission an architect for individual service phases.

*Source: The NRW consumer organisation, Falk Ostmann, Recht und Verträge beim Hausbau: Was Bauherren wissen müssen (Laws and contracts for home building: What owner-builders need to know), First edition 2013, pp. 32–35.