Your search resulted in 295 documents. Displaying 25 entries per page.
Formation of biofinishes on outdoor exposed wood; the impact of wood-oil combination and geographical location
2016 - IRG/WP 16-10864
Growth of dark moulds enables the use of a decorative and protective biofinish for wood, showing advantages compared to traditional wood-coatings in terms of sustainability and self-repair. Based on the formation of a uniform mould covering on oil treated wood during outdoor exposure, the utilisation of a biofinish is in development. Basic information is lacking on the correlation between exposure...
E J van Nieuwenhuijzen, L Ross Gobakken, M F Sailer, R A Samson, O C G Adan
Identification of the key factors influencing development of the blue stain fungi
2016 - IRG/WP 16-10872
Service life of wood is more and more frequently affected by aesthetic requirements than functional ones. In order to elucidate various aspects of service life, model house with façade elements made of 22 materials was built on the field test site at Department of Wood Science and Technology in Ljubljana. Colour and fungal disfigurement is among other parameters monitored on this house. In parall...
D Kržišnik, B Lesar, N Thaler, M Humar
Simulation of surface climate and mould growth on wooden façades
2016 - IRG/WP 16-20585
The weathering of wooden surfaces is normally caused by mould growth, lignin deterioration and leaching of extractives. For well insulated buildings, the effect of the interior climate on the outer surface is small and sometimes negligible. This paper describes simple models for surface temperature and moisture conditions on a wooden façade that can further be used to model weather degradation an...
T K Thiis, I Burud, D Kraniotis, L Ross Gobakken
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
Screening of fastener resistance in contact with untreated wood using different test designs
2016 - IRG/WP 16-30686
The performance of fasteners in wooden constructions is an important aspect especially regarding corrosion resistance. In an early stage corrosion of fasteners in untreated timber becomes often visible as a discoloration on the surface of the timber resulting in bad appearance of the product followed by complaints. In order to develop an accelerated test for the assessment of fastener performance ...
E Melcher, S Wolf, U Cera
Colorant Treatments to Enhance the Weathering Resistance of Western Red cedar
2016 - IRG/WP 16-40737
Western redcedar is renowned for its decay resistance, but, like most wood products, it requires frequent maintenance in many exterior applications to maintain its appearance. To provide adequate long-term performance in exterior applications, it must be protected against light, water, and disfiguring fungal growth. Colorant treatments, with and without preservatives, were investigated for their a...
R Stirling, V Landry
Variation in coating hardness during the EN 927-6 weathering test: influence of pigmentation
2016 - IRG/WP 16-40739
The objective of the SERVOWOOD project is to develop and establish European Standards that will facilitate the prediction of service life for exterior wood coatings. Within this project an extensive round robin exercise has been carried out by five partners to establish the repeatability and reproducibility of the EN 927-6 artificial weathering test. This round robin included the exposure of the I...
L Podgorski, L Malassenet, C Reynaud
Fungal growth on coated wood exposed outdoors: influence of coating pigmentation, cardinal direction and inclination of wood surfaces
2017 - IRG/WP 17-10896
The objective of the SERVOWOOD project was to develop and establish European Standards that will facilitate the prediction of service life for exterior wood coatings. One of the objective of this project was to study fungal growth of the field exposed panels. Two coatings applied in 2 and 3 coats were exposed for one year outdoors at 45° south: one solventborne (alkyd based) and one waterborne (a...
L Podgorski, C Reynaud, M Montibus
Monitoring of wood biodeterioration by infrared spectroscopy
2017 - IRG/WP 17-20607
The susceptibility of wood to deterioration by rotting fungi is intrinsically related to its chemical composition and the environmental conditions at its place of use, and if not detected in time, can cause enormous financial losses. The process of wood biodeterioration by decay fungi can be evaluated through laboratory accelerated test, in specific field tests, or through non-destructive techniqu...
E Meneses Oliveira, A Florian da Costa, J W Batista Braga
Influence of Weathering on Moisture Performance of Wood
2017 - IRG/WP 17-20619
Water performance of wood is besides the inherent durability the most important factor that influences on the performance of wood in outdoor, above ground applications. Therefore it is of significant importance to optimize the methods that are able to predict the moisture behaviour of wood in outdoor applications. In order to elucidate this questions, samples were prepared of oak (Quercus), sweet ...
M Žlahtič-Zupanc, B Lesar, N Thaler, M Humar
Weathering protection of European hardwoods through double modification
2017 - IRG/WP 17-30715
Beech and poplar were thermally modified, treated with melamine resin and both treatments were combined. The weathering performance (cracks and general appearance) of modified beech and poplar was assessed in natural weathering and correlated to material properties such as work in bending (WB) and Brinell hardness. In addition, the equilibrium moisture content after exposure of 12 months and subse...
G Behr, A Gellerich, S Bollmus, H Militz
Surface Protection of Wood with Metal Acetylacetonates
2017 - IRG/WP 17-40802
Metal acetylacetonates are coordination complexes of metal ions and the acetylacetonate anion. They have diverse uses as catalysts, cross-linking and curing agents and adhesion promotors. Some metal acetylacetonates can photostabilise polymers whereas others are photocatalysts. We hypothesise that the ability of metal acetylacetonates to photostabilise wood will vary depending on the metal in the ...
Yuner Zhu, P D Evans
Studying Weathering Performance of Coatings on Thermally Modified Wood
2017 - IRG/WP 17-40805
Thermal modification and degree of improved properties depends on wood species and treatment parameters. Southern pine and spruce are the two common wood species for decking, fences and siding in North America. This study was the first to evaluate coating performance when applied on oil-heat-treated southern pine and spruce wood samples. Water uptake, colour and gloss changes of samples were analy...
M Nejad, M Dadbin, P Cooper
Evaluation of coating applied in treated wood: experiences in Brazil
2017 - IRG/WP 17-40814
Weathering assays study the coating degradation caused by its exposure to the action of ultraviolet radiation, winds, heat and humidity. The use of test specimens in different arrangements and exposure angles is intended to reproduce various conditions in which a product can be used. The purpose of this paper is to present the efficacy of an oil-borne varnish applied on treated wood exposed to wea...
M F Natale, J M Vidal
Colour changes in unpainted wooden façades – Fifty Shades of Grey
2018 - IRG/WP 18-10903
In Norway the use of weathered unpainted, wooden façades has increased in popularity the last 20 years, both in single family houses as well as in multi-story and non-residential buildings. The benefit of using unpainted wood as façade material can be several: low maintenance costs, low environmental impact and low carbon footprint as well as contemporary and trendy aesthetic appearance.
The va...
K Zimmer, L R Gobakken, O Flindall, M Nygaard
Preliminary Investigation into the Natural Decay Resistance of Nigerian Grown Hevea brasiliensis and Mitragyna ciliata wood to Phanerochaete chrysosporium White-Rot Fungus
2018 - IRG/WP 18-10919
Wood is an important and versatile structural building material that finds applications in numerous uses. However, wood is also a biological material vulnerable to degradation by microbial activities; this is especially true in the tropics. Following the scarcity of highly durable species from our natural forests and the introduction of so many lesser used/durable wood species into the booming tim...
J M Owoyemi, U O Emmanuel
Visual appearance of unpainted wooden claddings during the first year of outdoor exposure: Evaluation of surface mould growth, lightness (L*) and wasp attack
2018 - IRG/WP 18-40841
This study addresses changes in visual appearance of unpainted wood materials exposed outdoors. Specimens of Norway spruce (Picea abies) Scots pine (Pinus sylvestris), aspen (Populus tremula), acetylated Radiata pine (Pinus radiata) and DMDHEU-modified Scots pine sapwood were exposed facing south in Ås, Norway for 60 weeks. During this period, surface mould growth development and wasp attack were...
S Karlsen Lie, L Ross Gobakken, G I Vestøl, O Høibø
Improvement of short rotation teak wood properties through thermal modification
2018 - IRG/WP 18-40842
Teak (Tectona grandis L.f) is one of the most popular tropical timber species. Nowadays, the source of long rotation teak is limited in the availability. Many wood processing industries use short rotation teak, which has lower quality especially in durability and dimensional stability. Heat treatment is an eco-friendly method improving dimensional stability and durability of wood. The objectives o...
L A Pratiwi, I W Darmawan, B George, A Merlin, C Gérardin, S Dumarçay, T Priadi, P Gérardin
Durability by design – a case study of the performance of wooden decks after 9.5 years of natural weathering
2019 - IRG/WP 19-20648
The service life expected for wood decking manufactured with poorly durable wood species, left untreated and exposed to severe environmental conditions such as high humidity and active biological agents, is usually assumed to be short (less than 10 years). The current classification of wood’s natural durability is based on EN standardised tests which do not fully reflect the real end-use conditi...
M Kutnik, M Montibus
Development of accelerated decay test for CLT using a fungus grown on agar medium
2019 - IRG/WP 19-20664
CLT is a large-scale wooden board which consists of several layers of sawn lumber stacked in altering directions. Therefore, a lot of large cross sections appear on all narrow faces of CLT. As water penetrates easily into timber from cross section, wooden material whose cross section is exposed to water in in a usage environment is susceptible to deterioration by organisms. Wood deterioration orga...
T Miyauchi, K Kambara, W Ohmura, T Mori, H Matsunaga, N Hattori
Gloss and hardness variations as early indicators of wood coating failure during weathering tests
2019 - IRG/WP 19-40866
The objective was to track early changes which ultimately will lead to coating failure when exposed to artificial weathering. Two different coatings (one waterborne acrylic paint and one solventborne alkyd stain) were exposed to artificial weathering for 2016 hours according to EN 927-6. Every 168 hours, samples were removed from the artificial weathering device for assessment (general appearance,...
L Podgorski
Potential Use of the Pigment from Scytalidium cuboideum and Chlorociboria aeruginosa as an UV-light Protection Additive in Oil Finishes
2019 - IRG/WP 19-40868
UV-light degradation of wood is one of the top reasons for consumer replacement of outdoor wooden structures. This type of degradation is seldom mechanical, and is instead often motivated by loss of aesthetics (graying). There are numerous commercial products available on the market that deal with this loss of color, many of which contain added pigments to ‘rejuvenate’ or ‘revitalize’ grey...
S M Vega Gutierrez, D W Stone, R He3, P T Vega Gutierrez, Z M Walsh, S C Robinson
The anti-weathering mechanism of extractives in thermally modified Scots pine
2019 - IRG/WP 19-40880
Results from the electron spin-resonance spectroscopy (ESR) analysis indicated that thermally modification of wood can inhibit the generation of phenoxyl radicals during UV irradiation and consequently lead to the increase of the color stability of wood. In order to clarify the evolution and role of extractives in thermally modified wood during the process of weathering, the compositions of aceton...
H Shen, J Cao
Effect of pretreatment of wood surfaces with a copper monoethanolamine solution on the natural weathering performance of semitransparent stains
2019 - IRG/WP 19-40881
Semitransparent stains for wood products are favored for outdoor applications in Japan because these finishes do not hide the wood grain. However, the photoprotective effects of wood surfaces are low, therefor there is a need to improve the weathering performance. We examined the natural weathering performance of semitransparent stains on wood pretreated with a copper monoethanolamine solution (Cu...
S Isaji, H Shibui, Y Hirabayashi
Wood protection techniques and natural weathering: their effect on aesthetics and preference of people
2019 - IRG/WP 19-50351
Current research successfully contributes to improving wood protection techniques. However, the vast majority of research on preventing degradation of wood ignores a critical aspect of making successful products and processes – user selection of materials, which may largely depend on the aesthetical qualities. Wood treatments change the tactile and visual properties of wood substantially and the...
D Lipovac, M D Burnard, A Sandak, J Sandak