Your search resulted in 437 documents. Displaying 25 entries per page.
Durability testing of mass timber building elements: a call for a collaborative trial
2019 - IRG/WP 19-40875
Mass timber buildings have captured the imagination of architects and engineers seeking more environmentally friendly building materials. The mass timber movement has tremendous potential to markedly increase timber use in mid-rise to high rise buildings. With great promise, however, comes great risk. Most mass timber structures that have been built or are being planned use no protective treatm...
J J Morrell
The impact of additional interior layers to the moisture dry-out and mould growth risk of CLT walls
2019 - IRG/WP 19-40876
The objective of this study was intended to determine the maximum allowable initial moisture content for CLT walls having both exterior and interior thermal insulation. A laboratory test was conducted, for which four test walls with two different insulation solutions and two different initial moisture contents were built. Based on the test results a simulation model was configured and simulations ...
V Kukk, J Kers, T Kalamees
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
Durability and climate change - implications for wood building structures
2019 - IRG/WP 19-50361
Sustainable building practices are rooted in the need for reliable information on the long-term performance of building materials; specifically, the expected service-life of building materials, components, and assemblies. This need is ever more evident given the anticipated effects of climate change on the built environment and the many governmental initiatives world-wide focused on ensuring that ...
M Lacasse
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
Performance of bio-based building materials – durability and moisture dynamics
2020 - IRG/WP 20-20666
When exposed to conditions favourable for decay, bio-based building materials can be susceptible to degradation. Their ability to withstand deterioration over time (performance) depends on the intrinsic or enhanced durability of the material as well as its wetting and drying behaviour. The effect of fungicidal components in wood is known since long. Other material characteristics, such as the mate...
L De Ligne, J Caes, S Omar, J Van den Bulcke, J M Baetens, B De Baets, J Van Acker
Studying amount, location and state of water in modified wood at moisture levels relevant for fungal degradation
2020 - IRG/WP 20-40889
Water is an essential parameter for fungal degradation of wood, but degradation primarily occurs at high moisture levels at water potential in the range of -4 to -0.1 MPa, which corresponds to 97-99.9% relative humidity. At these moisture levels, water is present in the wood structure both in and outside of cell walls. The majority of previous studies on the interaction between wood and water for ...
M Fredriksson, E Engelund Thybring, Ramunas Digaitis
Long-term field exposure of wood-plastic composites processed on a commercial-size extruder
2020 - IRG/WP 20-40894
Wood-plastic composites (WPC) contain wood fiber (or flour), thermoplastics and additives and are exposed to UV light, moisture, and biological deterioration in outdoor installations. Accelerated laboratory tests can help to predict the durability of WPCs, but long term evaluations are needed to validate these results. Field exposed above-ground WPC deck boards (30.5 x 139.7 x 609.6 mm) and in-gro...
R E Ibach, C M Clemmons, N M Stark
Impregnation of railway sleepers - Investigation of a system-sleeper as an alternative for creosote treated sleepers
2020 - IRG/WP 20-40896
For nearly 200 years wooden railway sleepers are impregnated with creosote. After initially using vacuum pressure processes for impregnation, empty-cell processes have been developed quickly and are used until today. Because of political developments, creosote will probably be banned on the European market in the near future. The Fürstenberg-System-Sleeper, which combines for Europe innovative as...
M Starck, A Heidel, C Brischke, H Militz
Durability of acetylated Radiata pine: Laboratory tests and performance in practice
2020 - IRG/WP 20-40899
Wood acetylation is an established process to enhance biological durability and dimensional stability of lower valuable wood species without the use of biocides. Acetylated Radiata pine (ACCOYA® wood) has been on the market for more than 10 years now, starting in 2007.
Numerous lab tests have confirmed the high durability of acetylated Radiata pine. Here, additional data with four Radiata pine ...
K Jacobs, W Scheiding, B Weiß
Studies on the material resistance and moisture dynamics of Douglas fir and Sitka spruce from Slovenia
2021 - IRG/WP 21-20677
Wood in outdoor applications is subject to various decomposition factors. Wood degradation can be prevented by construction details, biocide protection of wood, wood modification, or selection of naturally durable wood species. Unfortunately, the majority of timber species in Europe do not have naturally durable wood. Imported tree species represent a new pool from which we can draw wood species w...
M Humar, B Lesar, D Krzisnik, E Kerzic, R Brus
Effect of a Water Repellent Treatment on Moisture Behavior of Three Australian Hardwoods: A Preliminary Report
2021 - IRG/WP 21-40921
Wood is inherently hygroscopic and will sorb moisture either directly from the atmosphere or via capillary action. Moisture can have marked effects on wood properties and repeated wetting and drying creates dimensional changes that lead to physical damage. Exposure to elevated moisture levels also increases the risk of fungal attack.
Wood preservatives have long been used to minimize the risk of ...
B Hassan, J J Morrell, K Wood
Natural durability and moisture dynamics of commercially important European wood species after weathering
2022 - IRG/WP 22-10992
Wood is a frequently used material. Timbers’ mechanical properties, particularly its favourable strength-to-mass ratio, make them suitable for many uses. Current environmental awareness has led to its renewed importance as a building material. However, wood is susceptible to decay that severely affect its outdoor performance. This study investigated how weathering affects the natural durability ...
E Keržič, M Humar
Significance of the thermal design and the sorption isotherm shape in hygroscopic wood moisture dynamics and service life
2022 - IRG/WP 22-20682
Moisture dynamics are considered important for predicting the service performance of wood in exterior applications. Above a critical moisture content, water acts a softener on the structural polymer matrix of the wood cell wall, enabling the necessary diffusion of molecular species involved in the fungal degradation mechanism of wood. Water may enter solid wood in either liquid form or in vapor fo...
W Willems
Combining MRI and X-ray CT to monitor fungal decay of plywood and OSB in a lab test
2022 - IRG/WP 22-20683
Bio-based building materials, such as wood and wood-engineered products, are susceptible to degradation by decay fungi. In-depth knowledge on the intricate material-fungus relationship as well as performance data for many bio-based building materials are still lacking, and especially knowledge on how a material’s structure and moisture properties affect the degradation process is missing. Althou...
L De Ligne, T Núñez Guitar, C Vanhove, J Van Acker, J Van den Bulcke
Using satellite-retrieved soil moisture data to model the decay risk of in-ground timber
2022 - IRG/WP 22-20689
Satellite-derived soil moisture data from the Soil Moisture Active Passive (SMAP) was extracted for a 9 x 9 km point grid over Europe. The data was then used as input to a dose-response wood decay model based on terrestrial microcosm (TMC) tests. The resulting hazard map plotted dose as an indicator of in-ground wood decay based on differences in annual temperature and soil moisture characteristic...
P B van Niekerk, M Schönauer, B N Marais, C Brischke
Effects of Borax and Boric Acid as Fire Retardants on the Resistance of Pterygota macrocarpa Wood to Fire Tests
2022 - IRG/WP 22-30770
The combustible nature of wood as a building material, when exposed to hazards of fire underscores the reason for fire retardant treatments. Pterygota macrocarpa wood is commonly used by builders in Nigeria for roof and other structural applications. Therefore, this study was carried out to assess the effect of Borax and Boric acid on the fire-retardant properties of P. macrocarpa wood. Wood sampl...
J M Owoyemi, O Apogbona, T O Akinwamide
Steam Pre-conditioning Treatment Prior to Acetylation: Impact on Dimensional Stability, Moisture Response Behaviour, and White-Rot Fungal Resistance of Hevea brasiliensis and Mitragyna ciliata Wood
2022 - IRG/WP 22-40930
The effect of steam pre-conditioning treatment on the dimensional stability, moisture response behaviour, and durability against white-rot fungus P. chrysosporium of acetylated Hevea brasiliensis and Mitragyna ciliata wood species were assessed. Defect-free specimens of both species from the top, middle, and base positions were selected, prepared according to ASTM D143-09 & ASTM D-2017 standards a...
E Uchechukwu Opara, J Mayowa Owoyemi, J Adeola Fuwape
Premature adhesion failure of exterior wood coatings – The influence of substrate temperature at coating application and moisture accumulation during storage
2022 - IRG/WP 22-40937
The present study aimed at extending the knowledge about premature coating failures of industrially finished wood cladding. Two potential factors were studied: the influence of substrate temperature at coating application and moisture accumulation during storage on the adhesion of waterborne coating systems. In the first experiment, 4 batches of wood specimens were submitted to 4 different tempera...
U Hundhausen
Effect of densification of Eucalyptus nitens and E. obliqua on moisture uptake, swelling, decay resistance, and fire performance
2022 - IRG/WP 22-40946
Some Australian Eucalyptus species that are abundantly available have low natural durability and poor resistance to fire. These same species are also extremely difficult to treat with preservatives or fire retardants using conventional pressure treatment methods due to a large proportion of refractory heartwood. The aim of this research was to understand whether thermo-mechanical densification had...
B Hassan, J J Morrell, F Wiesner, W Wu, B Belleville, K C Wood
Moisture sorption behaviour of poplar and thermally modified poplar using dynamic vapour sorption (DVS)
2022 - IRG/WP 22-40947
The moisture sorption behaviour of wood has a critical impact on service life. In Europe, softwood is mostly used to manufacture engineered wood products such as cross-laminated timber (CLT) or glue-laminated timber (GLT or glulam). Yet fast-growing and widespread tree species such as hybrid poplar with or without modification, have potential to meet the increasing demand. This study shows the moi...
X Jiang, J Van den Bulcke, L De Boever, M Minsart, A Mignon, J Van Acker
Unlocking the potential of tropical fast-growing hardwood species
2023 - IRG/WP 23-11010
Social forestry or community managed forestry practices have been promoted as an inclusive way to mitigate climate change through the framework of the UNFCCC scheme of the Reduce Emission Deforestation and forest Degradation (REDD+) programme. Fast growing wood species are one of the least tapped social forestry commodities in Southeast Asia, and they have the potential to be upscaled to meet the ...
S Fauziyyah, R Wimmer, C Brischke
Effect of Moisture Cycles and Timber Treatment on the Performance of Screwed Connections
2023 - IRG/WP 23-20694
The impact of moisture in timber structures is associated with the deterioration of timber, and loss of mechanical performance. Methods have been developed to treat timber using chemicals to inhibit deterioration, however, water intrusion has much more immediate effects on the mechanical properties of timber associated with swelling and shrinkage of the wood. The effects of moisture on the mechani...
L Yermán, M Xiao, Z Yan, L-M Ottenhaus
Moisture performance of wooden shingles tested on the Golobar cable yarding
2023 - IRG/WP 23-20704
Wood is a traditional roofing material in Europe and other parts of the world. In the 17th century, wooden roofing was generally used on more important buildings, but today it is mainly used on huts and houses in the Alpine regions. As wooden roofing is expensive, we investigated the possibility of extending the service life of the roofing through material selection and details. The roof of the Go...
M Humar, B Lesar, D Kržišnik
Biological durability and wood-water interactions of sorbitol and citric acid modified wood – Effects on the expected service life
2023 - IRG/WP 23-40960
A high level of research activities on sorbitol and citric acid (SorCA) modified wood has been recognized in Europe over the last few years. As this treatment is close to entering an industrial-scale production, it is of interest to investigate how such treated wood performs upon long-term outdoor exposure. Hence, in this study Scots pine (Pinus sylvestris L.) sapwood was modified with aqueous sol...
K Kurkowiak, L Emmerich, H Militz