IRG Documents Database and Compendium


Search and Download IRG Documents:



Between and , sort by


Displaying your search results

Your search resulted in 12 documents.


Durability of surface coating systems. Mycologg - an accelerated mycological test.
2004 - IRG/WP 04-20301
Field testing and natural aging/degradation of test sample, e.g. coated wooden surfaces is a slow process. Accelerated tests focus on mechanical properties, water uptake or sometimes stain fungi. Artificially weathered coated panels are not easily compared with naturally aged panels, and show the importance of involving the biological component among the degrading facors. It is a need for acce...
L Ross Gobakken, J Mattsson, B Jacobsen, F G Evans


In-service performance of wood depends upon the critical in-situ conditions. Case studies.
2008 - IRG/WP 08-20382
Wood is a unique building material, but is by nature designed to deteriorate. A detailed understanding of the factors and interactions involved are important when working with service life prediction of wooden components in buildings. Wood may experience exponential fungal degradation caused by variation in the climatic factors within a small limited area and by minor imperfection in the wooden ...
L Ross Gobakken, J Mattsson, G Alfredsen


Growth conditions for fungal decay in wooden constructions – practical experience versus literature
2011 - IRG/WP 11-10758
Data regarding moisture and temperature requirements of decay fungi found in literature have been compared to experience from observations in a large number of Norwegian buildings. A number of selected situations are discussed, among those exposure to high relative humidity, exposure to free water and decay in the supposedly adverse conditions on Svalbard. The moisture content in wood has to be at...
M Sand Sivertsen, J Mattsson


Fungal damages in Norwegian massive timber elements – causes and measures
2019 - IRG/WP 19-40879
Massive wood elements are relatively new in Norway but the use is growing quickly, primarily the use of cross-laminated timber (CLT). Moisture performance of massive timber elements has been examined by some researchers, but more knowledge is needed. There is uncertainty regarding the need for vapour barriers or retarders in roof assemblies, and for practical reasons buildings are rarely assembled...
M S Austigard, J Mattsson


Effect of long-term immersion in fresh and salt water on mould growth on Scots pine (Pinus Sylvestris L.) wood
2020 - IRG/WP 20-10962
Wood exposed outdoors will eventually be degraded by fungi, depending on exposure and material characteristics. Numerous wooden constructions in the Røros municipality have existed since the 17th century, but wood used in recent repairs have decayed faster than expected. Before 1970 timber was mainly transported by log driving or rafting, and the logs were immersed in water for longer or shorter ...
M Sand Austigard, J Mattsson


Moisture and temperature conditions in an old, highly moisture-loaded timber building in the Røros municipality, Norway
2020 - IRG/WP 20-10966
A 150 years old log building near Røros, Norway, has been in active use as a cowshed since its erection. The animals are kept inside the cowshed all winter and this causes a situation of a high moisture load on the wooden floor, wooden walls and ceiling. Logging of temperature and humidity over one year shows that there are favourable levels of moisture in the wood and air for development of moul...
M Sand Austigard, J Mattsson


Introduction to the project ‘Deterioration and decay of wooden cultural heritage in Arctic and Alpine environments’ (ArcticAlpineDecay)
2022 - IRG/WP 22-10997
The Arctic is already affected by climate change, and this is expected to accelerate over the coming decades. Alpine regions in Norway are projected to face similar challenges. Current knowledge on Norwegian wooden cultural heritage in Arctic and Alpine regions is scattered and contains significant knowledge gaps. Historically, - scientists, sectorial governance, tourist trade and commerce have ma...
G Alfredsen, L Ross, A W Hegnes, M S Austigard, J Mattsson, N B Pedersen, A Sinitsyn, V V Martens, A-C Flyen


Characterisation of fungal decay in cable car trestles in Svalbard
2023 - IRG/WP 23-11031
The Arctic will be strongly affected by climate change. In Svalbard the coal mining industry were established in the early 20th century. All man-made structures and sites dating before 1946 in Svalbard are protected by law and considered as cultural heritage. This included the massive cable car trestles that are constructed from untreated Norway spruce and mounted directly into the soil. We hereby...
G Alfredsen, L Ross, M Altgen, I A Yakovlev, A-C Flyen, M S Austigard, J Mattsson, N B Pedersen


Decay pattern in external wooden structures
2025 - IRG/WP 25-11055
Decay in external wooden structures has historically been a universal problem of great concern. Despite this, the general understanding of where and why wood-decaying fungi are occurring is limited. The consequences of this are that decayed wood might not be detected and that measures to protect the wood against deterioration has limited effect. Wood decay in different geographical and climatic ...
J Mattsson, M S Austigard, A-C Flyen


Xerophilic mould fungi on new and historic wood
2025 - IRG/WP 25-11056
An examination of mould fungi in 35 medieval and ten 18th Century buildings shows mould growth to varying degrees on different surfaces. The analyses also show a rapid development of mould fungi on certain wooden surfaces in recent years. A significant difference in the growth between new and old wood is the clearly more extensive growth and different species composition of mould fungi on new wo...
J Mattsson, M S Austigard


Evaluation of decay detection drill data – a semi-quantitative approach
2025 - IRG/WP 25-11067
Decay detection drilling and pick testing are common methods for evaluating decay in structural timber. In this study 63 poles in snow fence trusses at Finse in Norway, where climate change is expected to increase decay hazard, were evaluated by both drilling and pick testing. The aim of this study was to 1: assess a novel method to translate qualitative evaluation of drilling data into quantitati...
M S Austigard, J Mattsson, G Alfredsen, L Ross, N Bjerregaard Pedersen


Fungal decay in cable car pylons in Svalbard - overview of results
2025 - IRG/WP 25-41026
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. Whilst the timber used in the constructions was assumed to be untreated Norwa...
G Alfredsen, M Altgen, M S Austigard, J Mattsson, M Nunez, L Ross, S Aarseth Tunstad, A Treu, I A Yakovlev, N Bjerregaard Pedersen