Lone Ross
Director
Authors
Kristina Bringedal Gedde Georgios Triantafyllidis Alessio Miatto Lone Ross Lizhen Huang Daniel Beat MuellerAbstract
Abstract The building sector accounts for a significant share of global material stocks and embodied greenhouse gas emissions. Material intensity (MI), defined as construction materials per unit floor area, is a key metric for understanding resource use and environmental performance. Existing approaches estimate MI for specific building types and cohorts but rarely explore additional factors that influence the structural element requirements. This study refines traditional methods by incorporating building geometry, number of floors, geographical context, construction methods, and regulatory changes, using Norwegian residential buildings as a case study. We focus on stud use in exterior walls to understand how their MI (kg/m 2 ) varies across buildings. Our correlation analysis reveals that construction year (ρ = 0.69) and energy efficiency standards (ρ = 0.51) are associated with higher MI of studs while building length shows a notable negative correlation (ρ = –0.38). Timber stud MI increases with footprint complexity and number of floors but decreases as building length and floor area grow. Snow load further contributes to increased stud MI. Studs' MI also varies across periods, reflecting changes in regulations and construction practices. These findings enhance our understanding of material use drivers in timber structures and provide a foundation for developing more nuanced building stock models to improve resource efficiency assessments and support targeted climate mitigation strategies.
Authors
Gry Alfredsen Geir Wæhler Gustavsen Lone Ross Jonas Niklewski Philip Bester van Niekerk Christian BrischkeAbstract
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.
Authors
Gry Alfredsen Michael Altgen Mari S. Austigard Johan Mattsson Maria Nunez Lone Ross Sverre Aarseth Tunstad Andreas Treu Igor A. Yakovlev Nanna Bjerregaard PedersenAbstract
Abstract This study uses a novel combination of DNA metabarcoding, light microscopy, decay rating, moisture dynamics, and chemical analysis to investigate wood decay in cultural heritage cable car pylons in Svalbard. Uniform design but varying ages allowed analysis of time-dependent decay. Light microscopy revealed the use of both Picea abies and Pinus sylvestris . Decay progressed more rapidly near ground contact, influencing density, lignin, and holocellulose content, with lignin increasing over time. DNA metabarcoding and microscopy revealed dominant brown and soft rot fungi, with greater fungal diversity near ground level. Several new fungal species were identified for Svalbard and the polar regions. In the context of climate change, this highlights the global importance of monitoring fungal decay in wooden structures. The study emphasises the need for updated species lists and continuous monitoring, as new fungi may affect conservation strategies. The interdisciplinary method offers deeper insight into microbial interactions than single-method approaches.
