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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2026

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Abstract

Abstract This study investigated the incorporation of various waste materials including wastepaper, Tetra Pak, wood chips and scrap tire fluff into flue gas desulfurization (FGD) gypsum and cement mortar matrices to produce sustainable composite materials. Four distinct composite types based on the waste materials were developed and evaluated for selected properties including thermal and acoustic insulation. The proportion of the waste materials was varied between 10 and 40 vol% of the base matrix. The compressive strength of the filled gypsum composites was in the range of 4.17–10.39 N/mm² while the pure gypsum was 11.38 N/mm². The addition of the wastes in gypsum composites reduced compressive strength by about 10% for the best recipe and as large as 60% for the worst combination. However, the measured strength still exceeds the strength of typical gypsum wallboard with a compressive strength of about 3–4 N/mm² for whole-board crushing tests and it is much lower for point loads. The normal-incidence sound absorption coefficient indicated that the waste-filled samples absorbed around 80% of the incident sound energy between 2000 and 3000 Hz, comparable to some commercial acoustic foams. The results highlight the potential of utilising these waste-based composites in environmentally friendly construction applications. Depending on the waste type and matrix used, the results revealed trade-offs between multi-functional performance and sustainability benefits.

2025

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Abstract

A survey including 3112 responses from individual end users of wood cladding, from Norway, Sweden and Germany, was conducted with questions related to their experience and preferences regarding cladding with and without coatings. Based on these results and established scientific understanding of Service Life Prediction (SLP) of wood cladding, two decision trees were provided to guide end users in selecting a suitable material to meet their expectations when planning a new cladding. This approach makes the users reflect on maintenance requirements and aesthetic changes rather than choosing a product solely based on initial aesthetic appeal.

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Abstract

To optimise the use of renewable materials in construction, it is essential to understand the factors influencing decisions throughout their design and service life. Life Cycle Costing (LCC) supports sustainable development by aiming to minimise long-term costs through informed planning of service life, maintenance, and replacement. Central to this is the engineering concept of limit states - Ultimate Limit States (ULS) for structural safety and Serviceability Limit States (SLS) for functionality. However, in non-loadbearing applications such as cladding, maintenance is often driven by aesthetic deterioration rather than structural concerns. These aesthetic limit states are subjective and influenced by user preferences, personality traits, and cultural background. In practice, undesired aesthetic changes are among the main reasons for cladding replacement in Europe, alongside fungal decay and modernisation. Premature replacement due to insufficient communication about weathering effects and maintenance needs remains under-addressed. By accounting for variation in user preferences, material selection can be tailored to support a longer service life. This study presents multi-country variation in climate-related perceptions of wood and user preferences for wooden cladding.

Abstract

A total of 212 iconic wooden cable car pylons were constructed for mining operations in Svalbard, significantly contributing to Longyearbyen's historical identity as a mining town. Fieldwork in Svalbard involved collecting wood samples from 22 of these pylons, targeting wood exposed both aboveground and ground proximity. While the timber used in the constructions was assumed to be untreated Norway spruce (Picea abies), light microscopy revealed that 25% of the timber members were Scots pine (Pinus sylvestris). Wooden beams exposed aboveground showed initial decay over the first 80-90 years, whereas severe fungal decay was observed after about 50 years in wooden poles inserted in the ground. Metabarcoding identified Ascomycetes and Basidiomycetes to be predominating in the wood samples and unveiled new fungal species for Svalbard, including four brown rot, five white rot, and sixteen soft rot species. Macroscopic and microscopic examinations confirmed more advanced decay in ground proximity samples, dominated by brown and soft rot fungi.

Abstract

Understanding the service life of wood products used outdoors is essential for end-users to set realistic expectations regarding material performance. Furthermore, reliable service life data is critical for assessing building costs, environmental impact, and carbon storage potential. The report compiles existing knowledge on the service life of wood in outdoor constructions in Norway. The relevant applications included are wood used in ground contact, decking, and external cladding, and the data are derived from field trials conducted in Norway. The primary aim is to update the service life tables from a report published in 2014. Additionally, the report provides a brief introduction to the topic of wood protection. Many factors influence the service life of wood products, with temperature and moisture being the two most significant. The service life of wood in constructions primarily depends on the application, the natural durability of the material, any wood preservatives used, the presence of wood-degrading organisms, architecture, and craftsmanship. Poorly designed construction details can act as moisture traps, leading to early fungal damage. Therefore, it is important to address future climate challenges with well-informed solutions for optimal wood use. Secondarily, service life depends on thorough and repeated maintenance.

Abstract

Wood is a renewable resource, but not an unlimited one. Circular use of wood can mitigate greenhouse gas emissions and spare virgin resources. To plan for the circular use of building materials, it is important to study the availability of building materials in the built environment and the materials liberated during renovation. There exist multiple studies on so-called material intensities in buildings (Amini et al., 2024; Arceo et al., 2021; Fishman et al., 2024; Nasiri et al., 2023), but few evaluate the material intensities before and after renovation. In this study, we try to fill the knowledge gap by preforming a case study of a log house from the 19th century, upgraded to a student residence satisfying the building requirements for new Norwegian buildings.

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Abstract

Reusing and recycling post-consumer wood can help mitigate GHG emissions and reduce the risks of biodiversity loss by saving primary resources. A robust understanding of the post-consumer wood composition and its cascading potential is critical to enable this. However, there is currently limited research on the topic. This study contributes to filling the knowledge gap by sorting 54 tons of post-consumer wood at two industrial recycling stations and one household recycling station in Norway and further developing a classification system with quantified cascading potentials for post-consumer wood. The results showed that 49–64 percent of the wood at the industrial recycling stations and 32 percent at the household recycling station was load-bearing and untreated solid wood. We argue that these categories have a good potential for reuse and recycling. The high percentages indicate an opportunity for increasing the recycling and reuse of post-consumer wood. However, we also discovered some misplaced preservative-treated materials and a percentage of fiberboards that exceed particleboard manufacturer limits, meaning that sorting before recycling is required. Furthermore, we investigated how the wood composition was influenced by the type of customer delivering wood to the recycling stations and found that households generally deliver lower quality post-consumer wood than industrial customers.