Your search resulted in 113 documents. Displaying 25 entries per page.
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
Evaluation of exposure conditions for wooden facades and decking
2009 - IRG/WP 09-20408
During their functional life, building components are exposed to moisture and other environment stress conditions in numerous ways. This is a fact that should be taken into account during manufacture, product development, designing and work execution of building components. For wood material, moisture stress and biological factors like mould and decay fungi are often critical in cladding and decki...
H Viitanen, T Toratti, R Peuhkuri, T Ojanen, L Makkonen
Modelling of onset of mould growth for wood exposed to varying climate conditions
2009 - IRG/WP 09-20414
A performance-based service life design format based on climatic exposure on one hand and “resistance” of wood against mould growth on the other hand, is presented in this paper. A limit state for onset of mould growth is defined as the occurrence of traces of mould observed by microscopy. A dose-response model is proposed by which onset of mould growth can be predicted for an arbitrary climat...
S Thelandersson, T Isaksson, A Ekstrand-Tobin, P Johansson
The Relative Performance of an Organic Preservative System under UC3A and UC3B Conditions using Two Test Methods
2010 - IRG/WP 10-20429
Coated L-joints have been used for decades to evaluate the performance of wood preservatives in protected environments. This study was conducted using matched coated and uncoated L-joints to simulate above ground protected and unprotect exposures. When exposed to constant moisture in a greenhouse environment, coated and uncoated L-joints give very similar performance results. In contrast, exposi...
C F Schauwecker, A Zahora, A F Preston
A Review on Conditions for Decay Initiation and Progression
2010 - IRG/WP 10-20444
This paper reviews the key publications available on service life prediction of exterior wood applications, critical conditions for decay initiation and progression, and the impact of decay on wood strength. While it is helpful to use climatic data to predict general trend of decay potential, more precise decay initiation and progression information is required by hygrothermal modeling for its dam...
Jieying Wang, P I Morris
Onset of mould growth – the effect of climate variability and different geographic locations
2010 - IRG/WP 10-20446
This paper presents a study on how climate conditions at numerous locations in Sweden affect the risk of onset of mould on wood sheltered outdoors. The results indicate that the risk is clearly higher in the south compared to the north of Sweden. These differences are mainly explained by colder and dryer winter periods in the north which is unfavorable for development of mould. The results also sh...
M Häglund, T Isaksson, S Thelandersson
Drying Rates and Mold Growth on Various Building Materials under Different Environmental Conditions
2010 - IRG/WP 10-20454
Mold growth on building materials is a major problem for homeowners. The most suitable method to control mold growth on building materials is to utilize design features, construction tools and practices that prevent moisture accumulation, and keep the wood as dry as possible. In order to achieve this, engineers and homebuilders have to know the effects of various temperature and moisture conditi...
Dian-Qing Yang
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
Decay initiation in plywood, OSB and solid wood under marginal moisture conditions
2011 - IRG/WP 11-20469
Hygrothermal models are increasingly used as research tools by building scientists and and design tools by designers to simulate heat, air, vapour, and water movements within and through building envelope and even to predict the consequences in terms of mould/decay growth and metal corrosion. This work was designed to generate data on decay initiation under marginal moisture conditions to support...
Jieying Wang, P Morris
Performances of Douglas fir in real outdoor use conditions
2011 - IRG/WP 11-20472
The European standard EN 350-2 classifies Douglas fir as moderately resistant to fungal decay on the basis of standardized laboratory and field tests. However, the lifespan expectancy of outdoor structures such as cladding, decking and elements of wood construction carpentry may also vary according to environmental conditions (climate, exposure to weathering), maintenance and design. An investigat...
M Kutnik, S Lepetit, S Le Nevé
Protective Levels of Borates in timber Foundation Piles 5 – 18 Years after In-situ Remedial Treatment in Areas with Wet Clay Ground Conditions. The Jerbor and Eurobor Protocol, Part 1.
2011 - IRG/WP 11-30571
Timber has been used as foundation piles and grillages for decades or even centuries. Since the late 1970s a method for investigate, analyze and treat building timber foundations in soft clay grounds against decay fungus with a biocide have been developed and used by the late professor Allan Jerbo. Settling of buildings in soft clay grounds is continuously monitored and if damages to the building ...
M Theorin, K-M Bandh
Eastern redcedar included sapwood: Resistance to mold and termites under laboratory conditions
2012 - IRG/WP 12-10765
The heartwood of eastern redcedar (Juniperus virginiana) frequently contains areas of light-colored wood. This “included sapwood” is considered to be a defect by some manufacturers. In this study, sapwood, included sapwood and heartwood samples from five eastern redcedar trees were exposed to mold fungi or to subterranean termites in a no-choice feeding test. Extractives content was also measu...
C Köse, A M Taylor
Long term durability of the heartwood of seven common softwood species in above ground conditions
2012 - IRG/WP 12-10771
The natural durability for wood in above ground use has been evaluated based on results after 11 years of exposure in a test site situated at the Danish Technological Institute in Taastrup, Denmark. Selected results for seven common softwood species exposed horizontally are reported. The test results cover samples with direct rain exposure (use class 3 of the European standard EN335-1:2006) and sa...
E Tang Engelund, M Klamer, T Mark Venås, B Lindegaard
Mold Control for Treated Lumber in Block-Stack Storage Conditions
2012 - IRG/WP 12-30588
The mold development and control for freshly treated and block-stacked wood have been evaluated using a green house mold testing method. The results for the mold resistance of several commonly used water boron preservative treatment systems, such as ACQ, Copper Azole, and borates with and without inclusion of mold inhibitors are presented. The data suggest that the different preservative treatme...
L Jin, P Walcheski, A Preston
The influence of microclimate on the moisture conditions in a Norway spruce (Picea abies (L.) Karst.) joint exposed to artificial rain
2013 - IRG/WP 13-20505
Wood structures outdoors are susceptible to decay if they are exposed to high moisture contents during long periods of time. Structures with joints that act as water traps are especially exposed since high moisture contents are reached in such positions. This paper presents a part of a laboratory study that concerns the relationship between the microclimate and the material climate, i.e. the moist...
M Fredriksson, L Wadsö, P Johansson
Termite Management and the U.S. Experience: A Case for Wood Treatment & Integrated Control
2015 - IRG/WP 15-30678
A brief overview of termite control is given using specific experiences from the U.S.A. Five major types of termite treatment now prevail: soil applied chemical barriers, in-structure chemical barriers (in-situ applied wood and foundation treatments), physical barriers, treated wood and termite baits. In general, ‘stand-alone’ pretreatments or ‘primary’ treatments are often discussed and ...
J D Lloyd, K van den Meiracker
Foundation piles: analysis of beech wood decay in service life conditions
2016 - IRG/WP 16-10858
Wood piles foundation system was largely used over decades. Thus, numerous buildings over the world are based on this constructive system. In the context of reduction of CO2 emissions in the building field of constructions, substitution of concrete by wood as material for foundation piles seems to be a promising alternative. However, fluctuation of the water table level in soil may promote fungal ...
Q Kleindienst, A Besserer, M-L Antoine, C Perrin, J-F Bocquet, L Bléron
Production of reactive oxygen species in the presence of oxidized iron and oxalate under conditions mimicking brown-rot fungal degradation of wood
2016 - IRG/WP 16-10861
The biochemical role of oxalate in the fungal solubilization of iron is well known, but additional information is needed on the role that oxalate plays in the brown-rot decay of lignocellulose. In this study iron sequestration from iron and iron oxide-hydroxides was assessed with regard to the function of a chelator-mediated Fenton (CMF) reaction and the generation of reactive oxygen species (ROS)...
Yuan Zhu, Liangpeng Zhuang, B Goodell, Jinzhen Cao, J Mahaney
On the effect of climate and exposure conditions on durability indicators and their potential for service life prediction of wood-based products
2016 - IRG/WP 16-20576
In order to encourage increased use of wood, different user groups need to be better informed regarding the variation in performance between different wood materials and the effect of different use classes. It is also important to provide good empirical data on the service life of wood products as input to for example life cycle assessment studies. In the current study the effect of temperature an...
G Alfredsen, C Brischke, P-O Flæte, M Humar, L Meyer-Veltrup
Variation in moisture content in field trials according to use class 3.2 conditions
2016 - IRG/WP 16-20580
Different test methods to determine the durability of wood in use class 3 (EN 335:2013) are available. Fungal degradation of wood requires liquid water. Different Standards (EN 335-1:2006; DIN 68 800:2011) specify the risk for decay with moisture content (mc) of above 20%. EN 335 (2013) does not specify moisture content but rather defined limited wetting conditions (use class 3.1) or prolonged wet...
S Bollmus, A Gellerich, H Militz
Performance of 3-iodo-2-propynyl butyl carbamate (IPBC) in L-joints under tropical conditions
2016 - IRG/WP 16-30688
The ability of 3-iodo-2-propynyl butyl carbamate (IPBC) to protect wood against fungal decay out of soil contact was evaluated using ponderosa pine L-joints at two exposure sites over a 12 year period. IPBC tended to provide better protection when formulated in an organic solvent and when applied using a double vacuum treatment. Performance also tended to be better when systems contained a water...
J J Morrell
Thermoplastic Plywood at Moderately Increased Thermal Conditions
2016 - IRG/WP 16-40735
New thermoplastic plywood material so-called GradaTM manufactured by UPM has vast potential in production of wooden products with new approach of manufacturing. This paper examines possibilities of including GradaTM material in skateboard deck production as a large use of plywood type construction in this manufacturing sector. Bending strength (BS) and tensile strength perpendicular to the surface...
R Réh, M Guoth
Wood Protection and Environmental Performance of Products - Impacts COST Action FP1407 Aims to Bring
2016 - IRG/WP 16-50323
Though many aspects of wood modification (chemical, thermal, impregnation) treatments are known, the fundamental influence of the process on product performance, the environment, and end of life scenarios remain unknown. To contribute to the low-carbon economy and sustainable development, it is essential to integrate interactive assessment of process parameters, developed product properties, and e...
A Kutnar
Comparative studies on the durability of English oak (Quercus robur L.) under in-service, field and laboratory conditions
2017 - IRG/WP 17-10881
The durability of many wood species varies due to differences in extractive content, anatomical features, growth conditions, and not at least in dependence of the respective exposure conditions either under test or in real life applications. And so does the durability of English oak (Quercus robur L.), which has recently been considered in the revised European standard EN 350 (2016) and is now cla...
C Brischke, L Meyer-Veltrup, A Soetbeer, M Höpken, E Melcher, J Trautner
An experimental study of mould growth and wood decay in timber frame walls
2017 - IRG/WP 17-20623
This paper deals with parameters related to the occurrence of mould growth and wood decay in timber frame walls. In a first part, the hygrothermal conditions inside a timber frame wall finished with brick veneer cladding are analysed to get an idea of possible moisture related problems. It is shown that, based on the VTT mould prediction model, there is a mould risk on the interface between the in...
M Vanpachtenbeke, J Van den Bulcke, I De Windt, J Langmans, S Roels, J Van Acker