Joining Cards - Investigation of de-constructable fastening and joining techniques for the development of mono-material interior systems made of cardboard

Concerning climate neutrality in the building industry, the established interior finishing systems can cause problems at the end of their life cycle in reuse as well as in recycling. This is a result of the heterogeneous use of materials as well as the applied method of joining elements. These problems are particularly relevant due to the scarcity of finite resources, the dynamics of urban spaces, and the future demands of cities and buildings due to climate change, with the resulting need to adapt interior design by replacing or completely deconstructing these systems.

In this context and to achieve a circular economy, a broad application of paper-based materials, as a renewable and multiple recyclable building material, in the form of directly reusable and durable building components, has great potential. Among other things, the fundamental suitability of paper-based materials for the building industry has already been investigated and demonstrated by the Japanese architect Shigeru Ban in demonstration buildings and in international research projects such as "BAMP! - Building with Paper" for temporary applications.

The resulting project goals for the exploratory study "Joining Cards" consisted of constructive concepts for standardized and deconstructable joined interior finishing systems made from paper-based components, built 1:1 investigation models, and a comprehensive knowledge gain on joining paper-based components.

For this purpose, concepts were developed and illustrated in the form of sketches, CAD drawings, and technical descriptions using architectural and constructive design methods based on literature research and analyses. This was done in individual work and in the context of concept workshops, in which existing concepts were discussed, analyzed, and detailed in larger groups and further concepts were developed through brainstorming.

Furthermore, selected concepts were translated into 1:1 investigation models. This included the definition of the concept- and model-specific parameters (e.g. element dimensions, materials, joining technology and means), the production of CAD drawings to control a cutting plotter, the manual processing of cardboard or paper-based components utilizing cutter knives, with a drilling machine, with pliers and with a Japanese saw, as well as the assembly of the individual components. Predominantly parallel to these activities, a qualitative evaluation was carried out based on the continuously gained knowledge. The evaluation criteria were material homogeneity, systematization, deconstructability, reusability, stability, load-bearing capacity, and innovative content.

As a result of the project, several basic interior finishing concepts were developed in various degrees of detail. This includes concepts for non-load-bearing interior wall systems, for suspended ceiling systems, in the area of floor systems, and for individual components (e.g. supports, planking). A further project result is the models of selected concepts, which were built on the basis of their underlying joining principle at a basic level and in different variations. In addition, one concept of an interior floor system and one concept of an interior wall system were combined to form a large-scale space-forming model. These two concepts are described and presented in this report as a selected project result based on the constructive design as well as the translation into the large-scale model.

As it was observed in the project, there is great research potential in deconstructable interior finishing systems made of renewable and multiple recyclable paper-based materials. This potential lies in durable and directly reusable (circular) building components as well as in the combination of paper-based components with metal components at the joining point. The former relates to manufacturing, assembly, and disassembly, as well as the use of interior finishing systems. If society is involved at the level of (co)design, a new approach and stronger connection to a form of sustainable construction can thus be created. Further research potential exists in the application of recycled and reusable paper-based components in standardized load-bearing structural elements (e.g. slabs). As well as, in the context of "buildings as CO2 sinks", in the implementation of the rapidly renewable building material straw (in the form of durable and circular e.g. board material) in interior construction.

Project management

Institute of Architecture Technology, Graz University of Technology

Institute of Architecture Technology
Graz University of Technology
Univ.-Prof. Dipl.-Ing. Architekt Roger RIEWE
Rechbauerstr. 12/I
A-8010 Graz
Tel.: +43 (316) 873 6300
E-Mail: riewe@tugraz.at
Web: www.iat.tugraz.at