Your search resulted in 348 documents. Displaying 25 entries per page.
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
Continuous moisture measurement (CMM) to detect failure of moisture resistance
2009 - IRG/WP 09-20422
A wood coating system will fail to perform properly after a certain time of weathering. From that moment, the substrate is especially prone to fungal attack. Moisture plays a key role on weathering performance, wood protection efficacy and decay susceptibility of wood. Therefore, knowledge of the moisture dynamics of the applied wood protection is of significant importance in the prediction of the...
I De Windt, J Van den Bulcke, J Van Acker
Wood properties influencing the penetration of Scots pine (Pinus sylvestris) sapwood with the wood modification agent furfuryl alcohol
2009 - IRG/WP 09-40470
The European standard EN 350-2 classifies Scots pine sapwood as class 1 (easy to treat). However large variations in sapwood penetration exist which affect a homogenous distribution of preservatives. Hence individual penetration schemes have to be developed and adjusted to the material most difficult to treat in order to provide adequate sapwood penetration. To ensure better economic process con...
K Zimmer, E Larnøy, G Koch
The effect of chemical changes on the wood-moisture relationships in thermally-modified wood
2009 - IRG/WP 09-40473
Small specimens of three wood species were thermally modified following twenty schedules in the 190-245°C temperature range for treatment times between 0.3 and 16 h. Five wood-moisture relations were subsequently determined, namely: anti-swelling efficiency (ASE), movement, hygroscopicity (adsorption and desorption), transversal swelling (radial and tangential directions), and equilibrium moistur...
M M González-Peña, M D C Hale
Diagnosis of failures in wood beams from historical house in Banská Štiavnica – Relations between ultrasonic measurements and bending properties
2010 - IRG/WP 10-20437
Various degrees of rot and other damages in ceiling beams with dimensions of 6500-8800 x 160-200 x 240-310 mm (length x height x width) situated in one historical bourgeois house in the UNESCO town Banská Štiavnica, Slovakia were determined visually and by the PUNDIT-plus ultrasonic device. Subsequently, for seventeen of the most bio-damaged fir (Abies alba Mill.) beams chosen for exchange were ...
L Reinprecht, M Pánek
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
Finite Element Modelling of the Checking of Wood Exposed to Accelerated Weathering
2010 - IRG/WP 10-20459
The surface checking that develops when wood is exposed to the weather reduces the visual appeal of treated wood products and can reduce the effectiveness of preservative treatments. There is strong interest in developing solutions to this problem and also a growing realization that such solutions may evolve from a deeper understanding of the mechanisms responsible for surface checking. In this pa...
S G Ribarits, P D Evans
TMT–Interlab–Test to establish suitable quality control techniques - Structure and first results
2010 - IRG/WP 10-40503
As a result of growing quality demands from manufacturers and end-consumers of thermally modified timber (TMT) recent scientific research activities are increasingly focussed on modification mechanisms and by this on the development of suitable quality control methods. To deepen the knowledge in modification mechanisms and to obtain a larger variety of scientific data for TMT depending on the trea...
C R Welzbacher
Impact of wood species on the performance of exterior wood coatings
2010 - IRG/WP 10-40519
To prolong the service life of a wooden construction the protective function of a coating is of utmost importance. The chemical composition as well as the wood-coating interface affects the performance of this protective layer and obviously wood species have an impact too. This paper discusses the influence of wood species on the overall coating performance. Therefore, a range of opaque waterborne...
I De Windt, J Van den Bulcke, J Van Acker
Moisture dynamics of WPC as basis for biological durability
2010 - IRG/WP 10-40520
The largest market for wood-polymer composites (WPCs) is currently decking. Although many products are commercially available, a proper standard for the assessment of the biological durability of WPC does not exist. Recommended standards for testing resistance against basidiomycetes should be completed with a method to bring the specimens in a worst case situation, obtaining a moisture level high ...
N Defoirdt, J Van Acker, J Van den Bulcke
Testing of decay resistance of sapwood and heartwood of thermally modified Scots pine and Norway spruce
2010 - IRG/WP 10-40523
Thermal modification at elevated temperatures changes the chemical, biological and physical properties of wood. One of the main targets of thermal modification is to increase the biological durability and decay resistance of wood. Although the effects of thermal modification on wood have been widely studied, the significance of sapwood and heartwood on the resistance of thermally modified wood has...
H Viitanen, S Metsä-Kortelainen
Effects of global climate change on mould growth - Interactions of concern
2010 - IRG/WP 10-50270
An evident change in climate the last decades has been recorded, and combined effects of increased CO2, elevated temperature and altered precipitation regimes have been observed to represent a change to the fundamental drivers within ecosystems. Growth of moulds, both in nature and on man-made constructions and objects, will most likely increase due to changes in the climate. The survival, the rep...
L Ross Gobakken
Chapter 12 - Treatment Groups of Bamboo
2007 - IRG/WP 07-10635-12
Study on distribution of CCA in three major bamboo species in
Bangladesh, full-cell pressure treated at green and dry conditions
revealed two treatment groups and some treating principles. Higher
adequate treatment for ground and water contact use is only
possible by treating problematic bamboo species pre-kiln dried up to
half of its FSP and non-problematic species pre-dried up to FSP
(20% ...
A K Lahiry
Theoretic discussion on the way and driving forces of moisture migration in wood during vacuum drying
2011 - IRG/WP 10-40538
Most of parameters in conventional drying cannot explain a lot of phenomena appeared in vacuum condition, so it is necessary to further explore the moisture migration way and driving forces in wood under vacuum condition. For the water movement channel in wood is very narrow, the characteristic of heat and mass transfer in wood is similar to that in microscale. This article applies theory of liqui...
Zhengbin He, Xueli Yao, Liqiong Chen, Songlin Yi
Improving our understanding of moisture and other durability-related properties of wood in building envelope performance prediction
2011 - IRG/WP 11-20468
Building science has become an increasingly important field in recent years with rapid changes in construction methods, building materials and consumer expectations. The field has also been brought to prominence by a few large-scale premature building envelope failures in a few regions across the world. Considerable effort has been put into developing hygrothermal models to simulate heat, air, vap...
Jieying Wang, P Morris
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
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
Influence of soil moisture, Sarawak soil types and decay types on decay susceptibility of rubberwood and kelempayan
2012 - IRG/WP 12-10780
Wood and soils are important natural resources of the land, the former widely used as structural supports in contact with the latter. Many low durability wood species exposed to soil contact has reportedly high incidence of decay failures in poorly treated and untreated materials depending on soil types, properties and soil microbial virulence. This paper probes the relationship of the main soil t...
A H.H. Wong, P K.F. Chong, J Sabang
Variation in two Postia placenta strains, MAD-698-R and FPRL 280 – mass loss, DNA content and gene
2012 - IRG/WP 12-10781
Brown-rot fungi such as Postia placenta are common inhabitants of forest ecosystems and brown rot fungi are also largely responsible for the destructive decay of wooden structures. The aim of this study was to compare two commonly used strains of Postia placenta – MAD-698-R and FPRL 280. Scots pine sapwood samples were exposed for two and eight weeks to both fungal strains. The following was inv...
N Thaler, G Alfredsen, C G Fossdal
Plywood under the scanner: linking moisture dynamics and 3D structure
2012 - IRG/WP 12-20491
Plywood is highly esteemed as a construction material. Yet, the influence of moisture on both strength and durability are important factors. Especially the dynamics of moisture desorption and absorption should be taken into account when assessing the quality of a panel, which is a fact for all panel materials. This paper therefore focuses on the monitoring of the moisture dynamics of plywood subje...
J Van den Bulcke, I De Windt, N Defoirdt, J Van Acker
Comparative studies on the moisture performance and durability of wooden facades
2012 - IRG/WP 12-20492
Wooden claddings are traditionally used in many parts of the world. Also modern structures are frequently made from timber and timber engineering panel products. However, wood has to compete with other cladding materials and its durability needs to assure sufficient functional and aesthetic service life. Besides many other factors the durability of a wooden facade is dominated by its moisture perf...
T Bornemann, C Brischke, J-M Lück
Moisture performance based wood durability testing
2012 - IRG/WP 12-20495
In the frame of a scientific cooperation within the Swedish research program ‘WoodBuild’ comparative field and laboratory durability studies have been carried out by the Technical Research Institute of Sweden SP and Leibniz University Hannover. One objective was to improve test methods as well as evaluation systems in order to facilitate the use of (field) testing for service life prediction. ...
L Meyer, C Brischke, A Pilgård
Biological performance of wood- and bamboo-polypropylene composites: Effects of particle content, particle size and Zn borate
2012 - IRG/WP 12-40577
Particle content and size of wood material in wood plastic composites (WPCs) can affect efficacy of WPCs against fungi and termites. This study evaluated fungal and termite resistance of WPCs manufactured by using two different levels of particle content (50 and 70%) and three different particle sizes (30, 60, and 100 mesh). In fungal resistance tests, Tyromyces palustris, a standardized test fung...
S N Kartal, S Aysal, E Terzi, T Yoshimura, K Tsunoda
Surface moulds and staining fungi on acetylated wood – effect of increasing acetyl content
2013 - IRG/WP 13-10797
Wood used in outside applications is susceptible to weathering and photo degradation, which often leads to surface discoloration, loss of brightness and surface deterioration. Research has shown that acetylated wood is more resistant against brown rot, white rot and soft rot, and more dimensionally stable than untreated wood. However, acetylated wood seems still to be disfigured by surface moulds ...
L Ross Gobakken, S Bardage, C J Long II