The Federal Office for Building and Regional Planning

Publication Study on reducing technical rule references in the Energy Saving Ordinance

BMVBS-Online-Publikation 07/13, Ed.: BMVBS, May 2013

Series: BMVBS-Online-Publikationen Published: May 2013

ITG Institut für Technische Gebäudeausrüstung Dresden
in co-operation with:
Ingenieurbüro Prof. Dr. Hauser GmbH, Kassel
Universität Kassel
Federal Ministry of Transport, Building and Urban Development, Berlin
André Hempel, Barbara Krämer-Zain

Federal Institute for Research on Building, Urban Affairs and Spatial Development (BBSR), Bonn
Andrea Vilz


Numerous technical building requirements are set by the Energy Saving Ordinance ("Energieeinsparverordnung (EnEV)"). These requirements are often defined by references to technical rules/standards. Some of these requirements have to be verified through mathematical proof, others can be verified without calculation. Only few requirements are not defined by technical rule references. In view of the ongoing evolution of the Energy Saving Ordinance and the referred rules/standards, means possibilities and practical approaches for a future reduction of technical rule references in the Energy Saving Ordinance have to be shown.

The objectives of the study shall be:

  • Overview of the actual technical regulation content for decision makers and users
  • Reduction of time-dependence of future EnEV revisions on revisions of technical rules
  • Restriction of the indirect influence of interested parties on the scope of the regulator - in particular for the calculation
  • Widespread avoidance of the other disadvantages of the traditionally combined use of the EnEV and the referred rules

An analysis of the legal principles of rule references in law is basal to the considerations made in the present study.

A rule reference, as understood in the present study, is any reference of a norm or rule that, seen individually, is semantically incomplete to a reference object in order to complete the norm or rule.

By references to technical rules, the regulation text can be kept free of extensive technical detail rules. The legislature uses external expertise and is, thus, exonerated. In doing so, the referred rule becomes part of the legal norm, while the latter takes over the rule's contents word-for-word. However, the influence on reading flow and the tearing-apart of text are detrimental.

References in legislation must comply with constitutional requirements. These relate to the principle of the rule of law, resulting in certain publication requirements, and the principle of democracy that requires law-making by democratically legitimate legislative bodies.

In the context of the present study, the distinction between static and dynamic references is important. A reference becomes a static reference by adding an exact date/version of the referred rule to the reference. In case of changes to the referred rule (revision, newer version, etc.), still, the referred version of the rule has to be used - for any changes to be accepted in the context of the referring legal norm, the legislature has to take action. Thus, static references provide legal certainty. In dynamic references, always the current version of the referred rule has to be used. Due to the lack of predictability and controllability, the legislative/regulatory bodies lose influence in case of changes to the referred rules. Thus, dynamic references in certain constellations are subject to constitutional concerns.

In the EnEV of 2009, which is still in use, there are about 100 static references to 24 different standards [1]. The number of static references and referred standards has increased significantly since the introduction of the Heat Insulation Ordinance ("Wärmeschutzverordnung") and the Heating System Ordinance ("Heizanlagenverordnung"). The static references to be found in the Energy Saving Ordinance have a different position in practice, and with regard to their need from point of view of the regulator. All static references found in the "EnEV" are checked for their necessity and each reference was rated mandatory/reasonable or unnecessary.

Foundation of the verification process according to the EnEV is the calculation procedure to be used. The fixed procedure results in a uniform calculation regardless of the user, while the requirement level is determined clearly and the calculation results are comparable. The use of individual system-preferring evaluation processes is avoided. Most of the standards found in the Energy Saving Ordinance are subject to almost steady revision/updating - e.g. for the inclusion of new knowledge in energetic evaluation, adoption to newly marketable technologies or for bug fixes. A harmonisation between the updating process of the EnEV and the revision of calculation standards (in particular the central standards series DIN V 18599) is difficult, because both are subject to certain uncertainties.

A workshop on the research project has been held with experts from interested parties. The results were presented and discussed and the resulting findings have been incorporated into the considerations.
Proposals for the implementation of possible alternatives

(1) Retaining the reference to standards in calculation procedures and parameters
From the authors' point of view, retaining the references to certain standards for the definition of the calculation procedure and essential characteristics is vital. From a legal perspective, these references must be dated to a specific level of the respective standard. An alternative to direct static references in the EnEV would be general (dateless) references to technical rules or standards, with the exact date of the referred material laid down in a list to be used together with the EnEV. Due to the legal and fundamental relevance of the referred technical rules, this model is only constitutionally permissible, if the said list is also composed by the regulator/legislature.

(2) Inclusion of definitions and characteristics
References classified as not necessary usually are references to definitions or characteristics. Concrete proposals to avoid such references were made - either through replacement by the actual definitions/characteristics or, in some cases, by deletion without substitution. Thereby, the additional amount of text was considered, so that the Text of the EnEV is maintained uncluttered and legibility.

(3) Editorial changes
Another way to reduce the number of references in the "EnEV", is the grouping of identical references into a sentence or paragraph. Here, the clarity and certainty of the must remain intact.

An overview of all referenced standards, including exact versions/dates, could preface the EnEV. Thus, repetitions of dates of rules/standards could be avoided.

The abstract is part of the German publication "Untersuchung zur Reduzierung technischer Regelverweisungen in der Energieeinsparverordnung" - BMVBS-Online-Publikation 07/13, Hrsg.: BMVBS, May 2013, Berlin
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