Your search resulted in 321 documents. Displaying 25 entries per page.
Climatic impacts on the moisture performance of wooden decking and facades
2013 - IRG/WP 13-20518
In outdoor usage wood is exposed to a variety of influences, which reduce its durability against biological deterioration and wetting. Besides many other factors the service life of wooden facades and cladding is dominated by occurring moisture loads on the one hand and their capability to withstand moisture on the other hand. Hence, climatic factors have a direct impact on the material climate an...
T Bornemann, C Brischke, G Alfredsen
Predicting the Rate of Decay, and the Potential for Misinterpretation of Proper Scientific Method
2013 - IRG/WP 13-20525
Predicting the rate of fungal attack in wood-based materials and its effect on properties remains the holy grail of wood products pathologists; however, achieving this goal is difficult because of the many variables associated with the process. This paper reviews some of the more important aspects of the decay process in relation to test methodology and then discusses how data are sometimes used b...
B S Goodell, J J Morrell
Method for determining the critical moisture level for mould growth on building materials
2013 - IRG/WP 13-20530
The natural conditions of relative humidity (RH) and temperature (T) in different parts of a building is rarely constant over time. Instead, RH and T often vary cyclically and may pose a risk of mould growth as these conditions are the two key environmental parameters that controls mould growth. Consideration to both humidity and temperature conditions and the susceptibility to mould in a material...
A Ekstrand-Tobin, P Johansson, G Bok
Moisture distribution in glulam beams with natural cracks observed with CT Scanning before and after rain
2013 - IRG/WP 13-20534
The way cracks in outdoor wooden constructions affect durability is an interesting topic, since a certain amount of cracks can always be found naturally in wood and glued laminated wood. The question in this was, can cracks lead water into the wood and thereby increase the risk for decay and reduce strength and service life. Moisture balance, i.e., water absorption and water distribution were stud...
K Sandberg
System treatments of Pinus sylvestris - influence on moisture, decay and discoloration
2013 - IRG/WP 13-30612
Biological activity can cause challenges for the use of wood in outdoor exposure. Decay and discolouring fungi influence the service life of wooden constructions, and the moisture content of the wood is often an important factor. The aim of this study was to evaluate the performance of different combinations of preservative/modified wood protection treatments and surface treatments for wooden deck...
A Schabacker, G Alfredsen, L Ross Gobakken, H Militz, P O Flæte
Hygroscopicity of wood after polyethylene glycol (PEG) impregnation and/or heat treatment
2013 - IRG/WP 13-40623
The hygroscopicity of wood after polyethylene glycol (PEG) impregnation and/or heat treatment was investigated by testing the water uptake, equilibrium moisture content (EMC) at various relative humidity levels, and contact angle of the poplar wood surface. The results showed that: (1) At the first moment, the heat treatment at temperatures lower than 160 ℃ did not reduce the water uptake be...
Weiyue Xu Yuan Zhu, Jinzhen Cao
Resistance of WPC against wood destroying fungi
2013 - IRG/WP 13-40627
The investigation of biological durability is a fundamental topic to assess the performance of Wood Plastic Composites (WPC) particularly for outdoor applications. In the last years, different test setups based on existing standards on the field of wood as well as the field of plastics were used for WPC. But the test methodologies give different information about the durability of the tested mater...
A Gellerich, S Bollmus, A Krause
Comparison of moisture loss and its increment during the rehearsal process based on natural drying and water soaking application with or without sealing the trial discs of Common black poplar (Populus nigra L.)
2013 - IRG/WP 13-40639
This study was subjected to be set up to prove the pattern of moisture loss and moisture increment within the same wood samples prepared as the discs (30x23±3 cm diameter) with or without the bark intact during drying and in the duration of the water soaking application. In this concept, wood was exemplified by Common black poplar (Populus nigra L.) of the five 12 year old trees that are grown in...
I Usta
Moisture and Fungal Durability of Wood-Plastic Composites Made With Chemically Modified and Treated Wood Flour
2013 - IRG/WP 13-40648
Evaluating the fungal durability of wood-plastic composites (WPCs) is complicated by the influence of slow moisture sorption. Recently, the American Wood Protection Association (AWPA) Standard Method E10, Testing Wood Preservatives by Laboratory Soil-Block Cultures, was modified to incorporate not only solid wood, but also wood-based composites and WPCs. To simulate long term WPC performance, cond...
B K Segerholm, R E Ibach
Critical moisture levels and mould resistance of five different wood treatments
2013 - IRG/WP 13-30632
Mould resistance of five different treatments were tested using two methods, a recently
developed method for the determination of critical moisture levels of building materials (RHcrit),
and ASTM D3273-94. The critical moisture level method exposed samples at 22 °C and 98, 92,
86 and 82% relative humidity (RH) for 12 weeks. ASTM D3273-94 was performed at 29 °C and
about 95% RH.
Treatments c...
G Bok, P Johansson, A Ekstrand Tobin, S Bardage
Performance standards for wood in construction – delivering customer service life requirements
2013 - IRG/WP 13-20537
There is increasing need for consideration of performance classification for wood products in construction, as evidenced by the CPR, warranty providers and end user demands for information. This means we need to radically consider how the tests we conduct on wood for durability (especially biological durability) can inform on service life and how they might if possible be translated into a perform...
E Suttie, C Brischke, F Englund, E Heisel, J Jermer, D Lorenzo, M Polášek, S Thelandersson, J Van Acker
Moisture dynamics of wood – An approach to implement wetting ability of wood into a resistance classification concept
2014 - IRG/WP 14-20557
Within the research programmes WoodBuild and PerformWOOD, wetting ability tests have been conducted with 25 wood-based materials. A first attempt has been made to establish factors for calculating the material resistance of wood materials to be implemented into a design guideline for timber structures. The approach looks promising, but further studies are needed to establish more reliable relation...
C Brischke, C Hesse, L Meyer, S Bardage, J Jermer, T Isaksson
Performance classification of wood in construction – drafting a user friendly European standard
2014 - IRG/WP 14-20545
The performance classification for wood products in construction is an extremely important topic in Europe and beyond – warranty providers and end users demand service life and performance information in the face of competition with other materials. The European project PerformWOOD has formalised and drawn together the on-going research to focus on generation of a material resistance factor for ...
E Suttie, C Brischke, L Meyer, J Van Acker, M Kutnik, E Heisel, F Englund, J Jermer, S Thelandersson, M Polášek, D Lorenzo
Moisture performance testing of wood – Practical experiences
2014 - IRG/WP 14-20546
Different methods are used to characterize the moisture performance of wood and to quantify the effect of moisture loads on the resulting service life. These methods can be divided into direct and indirect methods. Furthermore they can be distinguished by characteristics like continuous or periodical measurements and measuring local or global moisture content (MC). Furthermore each measuring metho...
L Meyer, C Brischke, M Kasselmann, C Rösmann
Moisture dynamics of wood and wood-based products – Results from an inter-laboratory test
2014 - IRG/WP 14-20539
In the frame of the European research project PerformWOOD in close liaison with the CEN task group TG EN 350 of CEN TC 38 WG 21 in total six research institutes teamed up and initiated an inter-lab trial (Round Robin) to investigate the suitability of different test methods to determine the wetting ability of wood. The moisture performance of wood and wood-based products has been recognized as key...
C Brischke, L Meyer, C Hesse, J Van Acker, I De Windt, J Van den Bulcke, E Conti, M Humar, H Viitanen, M Kutnik, L Malassenet
Communities of mold fungi in moisture damaged building materials
2014 - IRG/WP 14-20542
The critical conditions needed for the development of mould and decay fungi have been modelled for different building materials. However, current knowledge of indoor microbes growing on building materials relies on culture-based methods and more advanced molecular biological techniques should be employed to study the complex microbial communities in building materials. In this paper molecular biol...
E Sohlberg, H Viitanen
A screening of factors that might influence the result of laboratory decay tests
2014 - IRG/WP 14-20548
Laboratory fungal decay tests provide important tools for performance testing of wood materials. But they are also hampered with some uncertainties regarding reproducibility. In addition to variation between fungal species and strains the test conditions are also believed to have some influence. The aim of this study was to screen the effect of a selection of test parameters that might influence t...
E Larnøy, G Alfredsen, A Treu, S Kolstad
Critical parameters on moisture dynamics in relation to time of wetness as factor in service life prediction
2014 - IRG/WP 14-20555
The concept of natural durability or enhanced durability based on the presence of active ingredients having an impact on both fungi and insects is not the only parameter steering the material resistance. Complementary resistance to getting wet (wetting ability) and consequently the ease of drying afterwards will lead to a parameter related to the time a piece of wood will remain under such wet con...
J Van Acker, I De Windt, W Li, J Van den Bulcke
Improving dimensional stability of thermally treated wood by secondary modification – potential and limitations
2014 - IRG/WP 14-40664
The potential of treating thermally modified wood with melamine resin to improve the dimensional stabilization is tested in this research. Two different boards of poplar (Populus ssp.) were cut into two halves. One half of each board was thermally modified (T1 and T2) in a commercial process, the other half was used as untreated reference material. The material was thermally modified using the vac...
G Behr, K-C Mahnert, S Bollmus, H Militz
Modern Instrumental Methods to Investigate the Mechanism of Biological Decay in Wood Plastic Composites
2014 - IRG/WP 14-40674
Various instrumental techniques were used to study the fungal decay process in wood plastic composite (WPC) boards. Commercial boards exposed near Hilo, Hawaii (HI) for eight years in both sun and shadow locations were inspected and tested periodically. After eight years of exposure, both boards were evaluated using magnetic resonance imaging (MRI), while a selected area of the board exposed in sh...
G Sun, R Ibach, M Gnatowski, J Glaeser, M Leung, J Haight
Experiences with an industrial system for controlled thermal wood modification in pressurized unsaturated steam
2014 - IRG/WP 14-40678
Thermal wood modification in pressurized reactors has a long history, but these processes are to date industrially scarcely used, because of the relatively complicated process equipment, compared to the more common high-temperature processes in kilns at atmospheric pressure. However, based on our practical experience with the FirmoLin® process, supported by recent scientific findings, it is foun...
W Willems
Biological durability of natural fibre reinforced composites
2014 - IRG/WP 14-40681
Composite materials reinforced with wood or non-wood natural fibres have the potential to be a lighter and lower-cost alternative construction material. Until better availability and properties and a lower cost price of degradable polymers makes their use more prevalent, the application of natural fibre reinforcements in synthetic polymers is an intermediate step towards products that are complete...
N Defoirdt, I De Windt, J Van den Bulcke, J Van Acker
Interpretation of moisture monitoring data - Relevance of moisture content thresholds for fungal decay
2015 - IRG/WP 15-10839
It is widely accepted that besides temperature wood moisture content (MC) is the key factor when it comes to durability of wooden structures exposed to weathering. Many approaches to predict the service life of wooden structures have therefore been based on using wood MC as one major input-variable to develop dose-response relationships between material climate and decay response. However, to impr...
L Meyer, C Brischke
Remote sensing for detection of termite infestations—Proof of Concept
2015 - IRG/WP 15-10846
This paper reports the results of a search to discover the most cost effective and robust method of detecting Reticulitermes flavipes infestations in structural members of remote bridges, homes and other wooden structures and transmitting these results to internet cloud storage thus obviating routine travel to these structures for periodic visual inspections. Duplicate stainless steel tanks were c...
F Green III, R A Arango, C R Boardman, K J Bourne, J C Hermanson, R A Munson
Influence of artificial and natural weathering on water exclusion efficacy of wood
2015 - IRG/WP 15-20559
Water exclusion efficacy (WEE) is one of the most important properties of wood that contributes to the overall performance of naturally durable wood species in outdoor above ground applications. WEE is in strong correlation with moisture dynamics of wood, its hydrophobicity and can indicates susceptibility against wood decay fungi. Despite of the importance of this parameter, WEE is not completely...
M Žlahtič, M Humar