II. Generally Accepted Rules of Technology
A definition of the term "generally accepted rules of technology" is not found in the law, although this term is used in some regulations (e.g., § 3 Construction Regulations NRW, VOB Part B). The case law defines it as follows:
"Accepted technical rules are those principles and solutions that have been tested and proven in practice and have become established among the majority of practitioners."
Therefore, besides the theoretical component – i.e., the corresponding scientific findings – a practical component is also required: The procedure must have proven itself in practice. The rules of technology do not have to be established in writing.
The accepted rules may include:
[*]- VOB/C
[*]- DIN standards
[*]- uniform technical building regulations
[*]- European standards
[*]- manufacturer’s instructions for processing a specific product
[*]- provisions of the DVGW - German Association for Gas and Water
[*]statutory provisions (e.g., the Energy Saving Ordinance)
Accepted rules of construction technology are found primarily in DIN standards. According to case law, there is a presumption that DIN standards represent the accepted rules of technology. This means that the person who claims that a DIN standard does not correspond to the state of the art bears the burden of proof.
It should be noted, however, that there are also DIN standards that already lag behind the rules of technology. Such outdated DIN standards lose their significance as rules of technology.
An example of this is the sound insulation requirements of DIN 4109. The Federal Court of Justice stated in its decision of 14.06.2007 (Az. VII ZR 45/06):
“Moreover, it would be wrong to regard the sound insulation requirements formulated in DIN 4109, whether for a minimum standard or an increased sound insulation, as recognized rules of technology, irrespective of the construction methods available. The Senate has repeatedly pointed out that DIN standards are not legal norms but only private technical regulations with a recommendatory character. DIN standards can represent the accepted rules of technology or fall short of them ( ). The requirements for sound insulation are subject to dynamic change. On the one hand, they are guided by the current needs of people for peace and individual privacy in their own living spaces. On the other hand, they depend on the capabilities of the construction industry and the building industry, considering the economic interests of both contracting parties, to provide as extensive sound insulation as possible. Sound insulation values specified in private technical regulations cannot be used as accepted rules of technology if there are economically acceptable construction methods corresponding to the accepted rules of technology that can easily achieve higher sound insulation values.”
It should also be noted that the accepted rules of technology must be complied with at the time of acceptance of the construction services. This can become problematic if the rules of technology change during the course of construction. For example, if the Energy Saving Ordinance changes during the realization of a construction project, the project can be built according to the regulations of the originally granted building permit without legal building code problems. Nevertheless, there is a risk that compliance with the outdated provisions of the Energy Saving Ordinance in this case will constitute defective performance under civil law.
Furthermore, it must be taken into account that not every newly published DIN standard simultaneously represents the generally accepted rule of technology. General acceptance includes that the regulation has proven itself in construction practice.
Source: Practical note: The legal importance of technical regulations, aknw
Rhenish regards