Circular Standards: Development of a circular standard-detail-catalogue

The construction industry is a significant contributor to global final energy consumption (approx. 34%) , energy-related CO2 emissions (approx. 37%) and resource consumption (approx. 31%). In terms of shaping our environment sustainably and reducing these values, a holistic approach through a circular economy is expedient. The Austrian Circular Economy Strategy 2022 addresses this by formulating the requirements for buildings to incorporate flexibility of use, modular construction, separability and the reusability of components.

However, current construction practices, based on the methods of casting, welding, bonding, foaming and sealing, generally results in structures where selective dismantling (into components or building materials) or adaptation to future requirements is impossible, or requires significant efforts. This is determined early on in the planning process and during the design- and system development phase. As the actual products used are not yet known in this stage, a general requirement for the components and their structural composition is assumed. In most cases, this is done using reference products and associated planning catalogs, which provide standardized design solutions, so-called "standard details".

This is where the present exploratory study comes in. The aim was to develop new "standardized" deconstructable construction details in the sense of a circular construction. In this context, the ability to deconstruct is defined as the extent to which objects (products and elements) can be deconstructed without impairing the functionality of the object itself or surrounding objects during this process.

For this purpose, research and selection of standard details was carried out, following a (minor) redesign, to reflect the current Austrian building standard as best as possible. Experts from the field were consulted. The deconstructability of these standard details was then assessed. This was followed by a constructive redesign with a goal to achieve the highest possible degree of deconstructability. These details were again discussed and specified with experts from the field to assess the constructional feasibility. Finally, a renewed assessment of the deconstructability and the derivation of problem areas and potentials was carried out.

The project results include the identification of 18 constructive standard details, 18 standard details that can be more easily dismantled and the respective assessment of the deconstructability. As a further project result, the selected evaluation method ("Circular Buildings: Disassembly Potential measurement method, Version 2.0") was further developed. This report presents examples of three standard details (standard and more deconstructable design) including evaluation, as well as the further developed evaluation method.

As was established in the project, the selected assessment method offers great potential for application in the context of deconstructable and circular construction. However, there is also a need for further development. This concerns, among other things, the linking of the method to the planning process, the categorization of objects to be evaluated into groups by service life expectancy, the organization of the component layers according to accounting and service profiles as well as according to trades, the prioritization of the objects, the concretization and updating of the evaluation criteria as well as the integration of new evaluation criteria.

In the area of construction, it was determined that construction elements should be divided into meaningful groups (for a circular economy) and should be installed and dismantled as these groups. In addition, some constructions may require a construction system change in order to increase deconstructability. This means moving away from the construction standard, which could be done gradually. In addition, sealing and the bonding of building components have a significant influence on deconstructability. In general, there is a need for the development of deconstructable details on a larger scale in the area of construction. The current building standard should serve as a starting point. Experts from different areas of the construction industry (e.g. planning, building physics, construction process, statics) should be involved and solutions jointly developed to ensure the greatest possible practical suitability.

Project management

Institute of Architecture Technology, Graz University of Technology

Institute of Architecture Technology
Graz University of Technology
Rechbauerstr. 12/I
A-8010 Graz
Web: www.iat.tugraz.at

Arq. Dr. Techn. Maria Soledad Vidal Martinez
Tel.: +43 (316) 873 6301
E-Mail: marisol.vidal@tugraz.at

Dipl.-Ing. Dr.techn. Matthias Raudaschl
Tel.: +43 (316) 873 6808
E-Mail: matthias.raudaschl@tugraz.at

Dipl.-Ing. Clemens Berlach
Tel.: +43 (316) 873 6801
E-Mail: clemens.berlach@tugraz.at