No abstract

Indoor air quality can be adversely affected by emissions from building materials, consequently having a negative impact on human health and well-being. In this study, more than 30 natural building materials (earth dry boards and plasters, bio-based insulation materials, and boards made of wood, flax, reed, straw, etc.) used for interior works were investigated as to their emissions of (semi-)volatile organic compounds ((S)VOC), formaldehyde, and radon. The study focused on the emissions from complete wall build-ups as they can be used for internal partition walls and the internal insulation of external walls. Test chambers were designed, allowing the compounds to release only from the surface of the material facing indoors under testing parameters that were chosen to simulate model room conditions. The emission test results were evaluated using the AgBB evaluation scheme, a procedure for the health-related evaluation of construction products and currently applied for the approval of specific groups of building materials in Germany. Seventeen out of 19 sample build-ups tested in this study would have passed this scheme since they generally proved to be low-emitting and although the combined emissions of multiple materials were tested, 50% of the measurements could be terminated before half of the total testing time.

The EU funded project RE4 (REuse and REcycling of CDW materials and structures in energy efficient pREfabricated elements for building REfurbishment and construction) looks into opportunities for prefabricated, CDW timber elements (structural and non-structural) for circular buildings. Main goal is to minimise resource consumption for building construction but also waste generation related to building dismantling. An innovative design concept for a fully reversible, prefabricated, multi-story residential building from waste wood has been established that reflects robust but flexible and adaptable solutions to extend the buildings-life cycle. Reversible connections, reusable elements and recyclable materials shall minimise future waste generation, when such buildings reach their end of life. A prefabricated façade element manufactured for a two-story prototype shall deliver figures for easy installation, dismantling and future reuse. The study aims to show how current challenges can be overcome and design for disassembly can be promoted.