Your search resulted in 863 documents. Displaying 25 entries per page.
Mould growth on spruce claddings and the effect of selected influencing factors after 4 years of outdoor testing
2015 - IRG/WP 15-30671
Norway spruce (Picea abies) is the most frequently chosen wood species as claddings in façades in Norway, and is used both coated and uncoated. The visual changes that occur during weathering can be colour changes, abrasion or wear, blistering, flaking, and even cracks in the wood or coating, but more often growth of mould and blue stain fungi is the main challenge. A field test with synchronous monitoring of relative humidity, air temperature, material temperature and wood moisture content in Norway spruce claddings has been performed in southern Norway as part of the ClimateLife project. Visual evaluation of blue stain and mould growth according to EN 927-3 was performed, and evaluation data after 46 months exposure is presented. The objectives were to study the effect of 1) environment, 2) cardinal direction and 3) colour of the coated surface on growth of blue stain and mould fungi and to study the variation in relative humidity, air temperature, wood moisture content and material temperature. After 46 months exposure, the red coating system had generally the lowest mould ratings and the uncoated claddings had the highest. Of the white coloured claddings the ones facing south had lower mould ratings than those facing north, but the opposite were found for red coloured claddings. The relative humidity was higher in front of claddings exposed northwards and in a shaded environment compared to an open environment against south. In an open environment red coloured claddings had the lowest wood moisture content and highest material temperature, and red coloured claddings against south had the highest maximum material temperature.
L Ross Gobakken, G I Vestøl
Search for an anti-sapstain treatment for fresh radiata pine wood in compliance with European BPD norms: Field Tests
2015 - IRG/WP 15-30673
In response to the impending restrictions on the use of pesticide active ingredients developed to control the staining of fresh wood, as a result of regulation issued in 2009 by the European Union, a project was proposed to test an alternative anti-sapstain treatment that meets both the European restrictions and the performance required for an export-quality radiata pine fresh wood treatment. A se...
P Montes C, T Hanke W
Indentation and pendulum hardness tests: two convenient assessment methods of the performance of exterior wood coatings
2015 - IRG/WP 15-40689
Developing formulations of exterior wood coatings with long service life is a big challenge. For many years in Europe the performances have been mainly evaluated through weathering tests (within the EN 927 series) followed by visual assessment (blistering, flaking, mould growth, chalking and cracking), colour and gloss measurements, and adhesion tests. Very recently the importance of the mechanica...
L Malassenet, L Podgorski, M Truskaller, G Grüll
Investigation of Dimensional Stability and Coating Performance of Different Heat-Treated Poplar Wood Before and After Accelerated Aging
2015 - IRG/WP 15-40702
In this investigation, coating performance of heat-treated poplar wood (Populus tremuloioes) in different environments, before and after accelerated aging was studied. Specimens with 150×100×20 mm and 20×20×20 mm in dimensions were prepared. Heat treatments were performed in air, steam and linseed oil media. Specimens were coated by alkyd based stain. Adhesion strength before and after aging, ...
A Talaei, D Ansari Movahed, G Rassam
Durability of reaction to fire performance of FRT wood products in different end use applications – Methods and results
2015 - IRG/WP 15-40705
Fire retardant treatments (FRT) may considerably improve the reaction to fire properties of wood-based products and the highest fire classifications for combustible products can be reached, but the maintained reaction to fire performance e. g. in exterior applications needs to be addressed in order to form a basis for new and reliable wood products with improved fire performance.
A European Techn...
B Östman, L Tsantaridis
Above-ground performance of a buffered amine oxide treatment system against Mastotermes darwiniensis
2016 - IRG/WP 16-10855
Above-ground H2 field tests against Mastotermes darwiniensis were conducted in far north Queensland to assess the efficacy of buffered amine oxide treatments in the softwoods Pinus sylvestris and P. radiata, and the hardwoods Eucalyptus regnans and E. diversicolor. Untreated hardwoods and slash pine bait wood (P. elliottii) were severely attacked or destroyed, while untreated P. sylvestris was mod...
L J Cookson, R W Clawson Jr
Global survey on durability variation – on the effect of the reference species
2016 - IRG/WP 16-20573
Climate change due to anthropogenic emissions is the largest environmental challenge of our time. Forest-based value chains play an important role in reducing the accumulation of CO2 in the atmosphere. Maximizing the use of wood to tackle climate change requires improved understanding of the service life of timber products. This information can best be obtained from field testing and while there i...
R Stirling, G Alfredsen, C Brischke, I De Windt, L P Francis, E Frühwald Hansson, M Humar, J Jermer, M Klamer, M Kutnik, P Laks, I Le Bayon, S Metsä-Kortelainen, L Meyer-Veltrup, P I Morris, J Norton, T Singh, J Van Acker, J Van den Bulcke, T M Venås, H Viitanen, A H H Wong
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
Moisture induced risk and fungal development in various field test set-ups in and above ground
2016 - IRG/WP 16-20577
A high number of studies on the decay performance of wood in outdoor exposure have been conducted in the past. However, no testing methodology for wooden components exposed above ground reflecting the variety of different loads has been established so far. Many test protocols were modified in different ways throughout the years and results were often published in an encoded or incomplete way. This...
L Meyer-Veltrup, C Brischke
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
Bundle tests - Simple alternatives to standard above ground field test methods
2016 - IRG/WP 16-20581
Within this study we applied different new above ground test set ups to untreated Norway spruce (Picea abies Karst.) and Scots pine sapwood (Pinus sylvestris L.) which are frequently used as reference or control species in wood durability field tests. The overall aim of this study was to find a simple alternative method to the few standardized above ground field test methods, such as the L-joint a...
C Brischke, L Meyer-Veltrup
Measurement of Cell Wall Moisture in Acetylated Radiata Pine Using Low-Field Nuclear Magnetic Resonance
2016 - IRG/WP 16-20583
Understanding the interaction of water with acetylated wood is necessary to explain how the protective mechanism of acetylation functions. Low-field nuclear magnetic resonance is one technique for assessing water in wood. Pinus radiata earlywood sapwood samples were acetylated to various weight percentage gains and then analysed with this method. Increased levels of acetylation showed significantl...
H G Beck, C A S Hill
Expert versus multi-sensor evaluation of wood samples after short term weathering
2016 - IRG/WP 16-20587
Understanding the influence of weathering factors and the material degradation mechanisms are fundamental for modelling the weathering process of wood. The goal of this work was to investigate the combined effect of time and exposure on the physical-chemical mechanisms of wood weathering. Four exposure directions (North, South, East and West) were investigated. Experimental tests were performed fo...
A Sandak, J Sandak, I Burud, L Ross Gobakken, M Noël
Evaluation of field test data
2016 - IRG/WP 16-20594
The resistance against fungal decay and insect attack of wood can be highly variable, between boards and even within boards. The variability in durability is not always an issue, but for high demanding applications information about its reliability is required. This comprises the variability of outdoor performance. Durability testing in laboratory and outdoor exposures can provide a good basis to ...
F Bongers, C Brischke, J Van den Bulcke, W Gard, I De Windt, H Militz
Performance of copper treated poles and posts after three to fifteen years of exposure
2016 - IRG/WP 16-20595
Copper based wood preservatives are one of the most important wood preservatives for heavy-duty applications. Wood treated with copper-based preservatives performs excellent if applied according to preservative specifications. If used improperly premature failures might appear. In order to elucidate properties of copper treated wood in use, utility poles and posts treated with copper-based preserv...
M Humar, N Thaler
Engineering for Rural and Civil Development. Uni Performance of wood exterior structures above ground contact in Spain built with softwood species. The situation of cases in northern Spain
2016 - IRG/WP 16-20597
Across Europe is very common to find exterior structures build in sawn and glue-laminated wood. Most of these exterior structures used softwood wood species such as fir, spruce, larch and pine. In Spain wood exterior structures, as for example bridges, became more and more popular since eighties, when sawn and glue-laminated wood were utilized for building exterior wooden structures in overall Spa...
D Lorenzo, J Fernández-Golfín, M Touza
Accelerated Weathering Performance of Impregnated Wood Samples Coated with Zinc by Means of Plasma-Assisted Particle Deposition
2016 - IRG/WP 16-30682
Many different methods are currently applied for wood protection against outdoor conditions. The most important of these is the process of impregnation with liquid substances. However, this kind of wood preservatives cannot provide a long-term protection of wooden surfaces. Weathering-resistant surfaces can be obtained by applying UV absorbing agents. In this study, the influence of zinc particles...
A Can, H Sivrikaya
Laboratory and Field evaluation on Resistance of Thiacloprid-treated Pine Species to Termites in Mexico
2016 - IRG/WP 16-30687
The usage of Neonicotinoids for wood preservatives is common practice in several countries. Especially the active ingredient Imidacloprid is well established for this application due to its high efficacy against termites. (2Z)-3-(6-chloro-3-pyridylmethyl)-1,3-thiazolidin-2-ylidene-cyanamide, also known as Thiacloprid showed a good efficacy against Reticulitermes santonensis De Feytaud in efficacy ...
P Meckler, T Jaetsch, I Rodriguez
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
The durability of manufactured structural building materials
2016 - IRG/WP 16-40718
The projected market potential for Engineered Wood Products such as CLT (cross laminated timber) is very positive however, potential prolonged rain leakage or moisture exposure during construction and in-service could pose considerable concern for its durability and reputation. This research was conducted to assess the decay resistance of CLT and OSB (oriented strand board) in an accelerated trial...
T Singh, D Page
Incorporation of raw boron minerals to protect particleboard against decay and mold fungi, termites and insects
2016 - IRG/WP 16-40729
This paper evaluated the biological performance of particleboards incorporated with the raw boron minerals ulexite and colemanite against decay, mold fungi, termites and insect larvae in comparison with that of particleboards with zinc borate, or boric acid plus a borax mixture. The results showed that ulexite and colemanite were highly effective against the decay fungi and termite attack in labor...
S N Kartal, E Terzi, P Gerardin, C M Ibanez, T Yoshimura
The durability of natural and thermomodified black poplar wood and Scots pine sapwood after two years of external exposition
2016 - IRG/WP 16-40730
Natural biological durability of many European wood species is considered to be relatively small, particularly in a ground contact conditions. This is due to the exposure of the wood to the range of biological and atmospheric destructive factors. This may to limit the scope of application of the wood of these species, particularly in construction. The biocides are often used for wood protection in...
A Fojutowski, A Kropacz, A Noskowiak
Hygrothermal performance of ventilated wooden cladding
2016 - IRG/WP 16-40733
The risk for an attack of wooden claddings by decay and discolouring fungi strongly depends on the moisture and temperature conditions in the building envelope. The design of the cladding has a major influence on its hygrothermal performance. In the present study, different wooden ventilated cladding designs were investigated at a test house in Mid-Norway for four years. The objective was to incre...
K Nore, U Hundhausen
Marine Borer Resistance of Acetylated and Furfurylated Wood – Results from up to 16 years of Field Exposure
2016 - IRG/WP 16-40756
Furfurylated and acetylated Scots pine sapwood has been tested since 1999 in a marine field with high marine borer activity. In 2004, two test groups with acetylated southern yellow pine (product later known as Perennial Wood™) were put out and over the whole test period differently furfurylated wood (later marketed as Kebony®) test groups have been started. Furthermore, some combinations of mo...
M Westin, P Larsson Brelid, T Nilsson, A O Rapp, J P Dickerson, S Lande, S Cragg
Development of methodologies to evaluate tanning blocking coatings
2016 - IRG/WP 16-40760
In Europe an increased interest in using home-grown hardwoods as sustainable and renewable construction materials started a few years ago. Amongst these species oak and chestnut are two interesting candidates as their heartwood contain a significant amount of tannins which contribute to their natural durability. To avoid wood greying and dimensional variations, oak and chestnut must be protected b...
C Reynaud, L Podgorski