Certification of reused materials
Although there is considerable interest and willingness, there are obstacles that must be overcome. Bergström points out that pre-used building materials do not necessarily have poorer quality, but that it is more difficult to know exactly what you have to work with. If a developer buys newly manufactured material, they know what requirements they can set, where the responsibility lies if the requirements are not met, and, ultimately, what the material can be used for.
“That’s why we’re working to develop quality criteria, with the possibility of certifying and labelling reused materials. We should be able to answer what it means for requirements regarding things like acoustics, moisture, and strength when the material has been in a certain environment for a certain time. Knowing that the building material can be used directly or whether it needs to be restored creates greater security for the clients, and thus the procurers can also more easily demand a certain proportion of reused material in a new building.”
RISE is working with Fabege, NCC, Vasakronan and others in the Återhus – Att bygga hus av hus (Eng: Re-house – Building Houses from Houses) project. In the Stockholm district of Haga Norra, almost 70% of a new building has been built from materials from an old vehicle workshop and car showroom. Even the old joists could be moved to the new building.
“It really is possible to use a lot of the old material. Based on inventories, decisions can be made – before a new building is designed – about which materials can be dismantled and reused. Work is underway in various development projects to determine how different building materials with different functional requirements can be reused. For example, how can the fire rating of old fire safety doors be retained or how can the porcelain from old toilet seats be used while replacing the flushing mechanism?”
Local initiatives create new markets for reused materials
Bergström points out that there are now many local initiatives to create markets for reused materials. At the same time, tools are needed that create a better national overview, and tools used for digitalisation and traceability can help. One vision would be a single, national database to search for products, which could then be entered directly into the digital models at the drawing stage.
“Since I started working at RISE in early 2022, I’ve realised that different fields need to work together to make reuse possible,” says Bergström. “This includes, for example, architecture, physical planning, and construction processes, as well as knowledge of moisture and microbiology, life-cycle assessments, and, of course, quality assurance and certification. RISE is involved in all these fields, and I’m convinced that a lot will happen in the coming years. In addition to better planning, better use of existing buildings and, of course, renovation and material recycling, reuse will be a way to reduce both resource use and climate impact from the construction sector.”
Photo:
Fabege
