Article

Wood as a Sustainable Building Material

Authors:
To read the full-text of this research, you can request a copy directly from the author.

Abstract

Wood is the most widely used building material in the United States because of its efficiency, durable, and usefulness. One of the greatest attributes of wood is that it is a renewable resource, it has low carbon impact and low embodied energy. The amount of energy needed for producing wood products is much less than comparable products made from other materials. Carbon in wood remains stored until the wood deteriorates or is burned. Architects, product designers, material specifiers, and homeowners are increasingly asking for certified building products that are from sustainable resources. More than 50 different forest certification systems in the world represent nearly 700 million acres of forestland and 15,000 companies involved in producing certified products. In terms of forest acreage under certification, Forest Stewardship Council (FSC) and Sustainable Forestry Initiative (SFI) dominate in the United States.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the author.

... Over the last three decades, many numerical and experimental studies, including Aktas ß et al. (2009( ), Jairaj et al. (2009, Romano et al. (2009), and Smitabhindu et al. (2008) for various solar dryers, have been carried out. Most solar dryers were designed for specific drying materials or climatic conditions. ...
... The energy embodied in the absorbers contributed 44% to the total EE. Since timber is a low embodied-energy material (Falk, 2009), and since concrete has a relatively longer life (does not require any replacements over the service life) both the frames and the floor of the kiln had the smallest EE (2% and 3%, respectively). ...
Article
An innovative methodology for the performance evaluation of solar dryers, which considers the total life-cycle (LC) energy effectiveness in present-value terms, has been proposed. In this method, the performance of solar dryers has been defined in terms of a set of performance parameters, called present value performance indicators (PVPIs). By applying the concept of unsteady-state mass and energy balances for solar kilns, and using known diffusion and heat transport equations from drying theory, a mathematical model was constructed and subsequently solved to predict the future thermal energy inflows and outflows as part of the assessment of the performance parameters. In order to illustrate the overall methodology proposed in this study, the model has been applied, as an example, to a case-study greenhouse-type solar kiln (i.e. Oxford) in the context of hardwood drying in Australia. The current methods used for the performance evaluation of solar dryers have also been reviewed, and it was found that the proposed method was likely to overcome the shortcomings and inadequacies of the current practices for assessing the performance of solar dryers. A sensitivity analysis was carried out in order to assess the robustness of the estimated performance indicators against the uncertain parameters.
... 6 Juliana Cortez-Barbosa, UNESP-Itapeva, Brazil, jucortez@itapeva.unesp.br 7 Marcos Tadeu Tiburcio Gonçalves, UNESP-Itapeva, Brazil, marcostadeu@itapeva.unesp.br 8 José Nivaldo Garcia, USP-ESALQ, Brazil, jngarcia@usp.br ...
... Timber as a building material is positively associated with well-being, eco-friendliness and aesthetic, which are important factors in the choice of a building [6]. Few construction materials have environmental benefits offered by wood [7]. ...
Conference Paper
Full-text available
Despite the promising future to industry in Brazil, most production sectors still suffer with the access to newer industrial technologies. Some very specific and limited incentives have been offered by the local Government to stimulate these companies. However, the forestry-timber sector hardly has access them, due to the several barriers and bureaucracies. Together with other factors, it is a visible reason to the lack of the renovation of their production lines, as well as the improvement of their industrial technologies. Industrial parks with modern technology contribute directly to products which better quality, and it could be a favourable way to the Brazilian development in industrial aspect. For that reason, it is important to perform studies to stimulate this sector. This study aims to verify the situation of the timber machinery of the wooden housing manufacturers in the Brazilian State of São Paulo. It was realized through a survey applied directly to the companies' owners. This work revealed that the largest share of these companies of São Paulo State presented update equipment to produce wooden houses. Nevertheless, these companies still could improve the technology of their manufactures with robotic and automated machinery, looking for a better productivity.
... The absence of wood in its most usual forms would imply a very different civilization than current, insofar as wood was present in the ages of stone, iron and bronze, contributing to the advancement of humanity, largely because it is a renewable material (Junior and Dias, 1997). Few building materials have environmental benefits offered by wood (Falk, 2010). Of all the conventional materials for construction, wood has a great relationship resistance / weight, and also it presents a great facility in the production of many manufactured objects, as well as it propitiates an efficient thermal insulation (Pfeil and Pfeil, 2003). ...
... Of all the conventional materials for construction, wood has a great relationship resistance / weight, and also it presents a great facility in the production of many manufactured objects, as well as it propitiates an efficient thermal insulation (Pfeil and Pfeil, 2003). Unlike metals and fossil-fuel-based products (plastics), our forest resource is renewable and with proper management a flow of wood products can be maintained indefinitely (Falk, 2010). Szücs (2006) notes that reforested wood is a noble product, which it has many beneficial characteristics in its use as construction part or element, and it has favorable conditions to generate comfort for the users. ...
Article
Full-text available
The building technique of light wooden framing, i.e., woodframe, represents a great innovative goal of construction, due to the very efficient levels of rationalization of material, operational flexibility and productive agility. In addition, excessive use of natural materials of renewable character in the woodframes, as the wood of planted forests, contributes to sustainability, a desired factor in most modern homes. In recent years, Latin American countries have suffered from the constant housing deficit, which destroys the possibilities of the first property by the neediest populations. Therefore, it is necessary to propagate studies, research and information on industrialized housing construction techniques, such as woodframe. This study focused on the exhibition by a state of the art of this innovative wooden housing typology, emphasizing its advantages, importance, types, and its current panorama in the regions in development stage, such as Latin American countries. Currently, the woodframe is known as a modern wooden residential technique, and it is conquering the public of all kind of economic classes, because of its innovation, lightness, competitive costs, and also by the efficient levels of sustainability, cleanness, assembly time, and rationalization of raw materials.
... Particular attention has been paid to reducing the amount of carbon emitted by buildings (Jeong et al. 2012), which account for approximately 25% of total worldwide carbon emissions (Cho et al. 2019). Wood, as a sustainable resource, has re-emerged as an attractive building material, and demand for wood construction material is steadily increasing (Falk 2009). If new construction of buildings in Europe is planned to be wooden, carbon storage is equal to maximum 47% of European cement industry CO 2 emissions (Amiri et al. 2020). ...
Article
Full-text available
The article deals with the effects of bulk density on thermal conductivity in specimens of 15Korean woods (Zelkova serrata, Pinus densiflora, Cornus controversa, Betula schmidtii, Betula platyphylla var. japonica, Ginkgo biloba L.,Cedrela sinensis A. Juss., Fraxinus mandshurica, Ulmus davidiana var. japonica, Prunus sargentii Rehder, Paulownia tomentosa (Thunb.) Steud., Larix kaempferi (Lamb.) Carrière, Robinia pseudoacacia, Kalopanax septemlobus and Tilia amurensis).The results of this study were compared with previous studies performed on wood specimens fromChina, India, and Turkey. Consistent with these previous studies, bulk density and thermal conductivity were positively correlated in Korean woods, and a simple regression model with a very high correlation of R2(94%) was obtained. Interestingly, we observed some variation between our simple regression models and those generated by previous researchers who had examined non-Korean woods.
... Signifi cant technological differences between the individual producers primarily come down to the thickness of manufactured layers, their strength class, and the systems of joining timber in terms of length, width and thickness. Glues and limit dimensions of the obtained elements also play an important role (Falk, 2010(Falk, , 2011Brandner and Schickhofer, 2008Brandner, 2014;Brandner et al., 2016). ...
Article
Wood, which is a natural and renewable material, is gaining increasing appreciation again and it is more and more commonly used in the building industry. The use of wood has been improved due to the application of modern bonding technologies (e.g. Glued Laminated Timber, Cross Laminated Timber), the development of modern production technology and improved methods of wood protection from fire. As large-size assortments of constructional timber in the form of light beams and boards are available on the market, it is possible to make stable and durable joints between individual constructional elements of a building. Among wood materials used for construction, CLT is increasingly used. It is applied in the construction of single-family houses, residential buildings, multi-storey buildings, public buildings, industrial and retail buildings as well as bridges. CLT was developed as a result of European research how to use short wood, left after the elimination of faults, for private construction. The trend very soon spread to the building industry in North America, Australia and Japan. CLT was more and more commonly used in multi-storey buildings due to its higher seismic resistance. At the beginning of the 30-year history of CLT, the use of this building material was minimal. However, due to the ecological trend and a wide range of economic factors (the value of material used and costs of production combined with high precision of finished products), this technology gained significant popularity. The surge of interest in wooden constructions also resulted from better distribution channels and technical approvals for different concepts of wooden construction boards. The following countries are leaders in the production and use of CLT: Austria, Germany, Switzerland, Sweden, Norway and the United Kingdom. In recent years, New Zealand and Australia have joined this group. CLT boards are exported to North America, Japan and Russia. The surge of producers and investors’ interest in CLT boards results from the production process diversity and construction variability. In consequence, there is an increasing number of concepts specifying the range of product application, depending on its strength and resistance.
... The results of this interpretation show that, in some implementations, bamboo has marked by a high "factor 20" environmental impact, a 20 times less load on the environment than compared to some alternatives (Van der Lugt et al. 2006). Wood and bamboo have renown in the green engineering technology industry recently because of their environmentally promising characteristics: a natural process can replace them, biodegradable, confine carbon from the atmosphere, low in combined energy, and providing less pollution in development than concrete or steel (Falk 2009 andMahdavi et al. 2011). Bamboo is a green material that can substitute to wood for reasons that, bamboo can be crop in 3-4 years from the time of plantation as compared to timber which takes decades (Lakkad &Patel 1980 andAmada et al. 1997). ...
Article
Full-text available
This study investigated the thermal characteristics for organic thermal insulation materials developed from single-layer particleboard from bamboo-waste and analyzed concerning fire retardant ability. The Differential Scanning Calorimetry conducted the precise heat capacity extent (DSC), Pyrolysis Combustion Flow Calorimeter and Scanning Electron Microscope (SEM) are utilized to characterize the materials. The exothermal value was observed in all of the DSC curves with a high middle part content up to an average of 13.65 mW. Beyond that consideration, the bottom and top part specimen are two comparable value with smaller exothermic peaks appeared. SEM of unidirectional fiber causes the bamboo to have strength in the direction of bamboo fibers. Cellulose for middle part had the highest quantity of carbon. Interfacial adhesion using epoxy resin (C 21 H 25 C 105) of the material is effectively enhanced after the surface modification of the fiber. Pyrolysis assessment reveals that the primary stage at 68-89°C is the exothermic dehydration of the biomass with the release of water and low-molecular-weight gases like CO and CO 2. Thermal analysis shows that the increment of heat distortion temperature can reach 341 0 C, and the thermal stability is significantly improved. Conclusively, Philippine bamboo as green composites materials does not only have quality thermal and mechanical properties but also have a good flame retardant ability.
... The results of this interpretation show that, in some applications, bamboo has marked by a high "factor 20" environmental impact, a 20 times less load on the environment than compared to some alternatives [1]. Wood and bamboo have renown in the green engineering technology industry recently because of their environmentally promising characteristics: a natural process can replace them, biodegradable, confine carbon from the atmosphere, low in combined energy, and providing less pollution in development than concrete or steel [2,3]. ...
Article
Full-text available
Green engineering investigated as a possible organic green material in the combustion process and heating applications. A bioreactor system processed Dendrocalamus asper bamboo culms as green engineering materials to the industrial process that produces valuable elements from a natural treatment by soaking with an average of pH 7.6 level of seawater. Pyrolysis Combustion Flow Calorimeter and Differential Scanning Calorimetry (DSC) to utilized the precise heat capacity extent to characterize the materials. A waste product in this process is the activated carbon, which is highly in demand for water cleansing system and sold to neutralize the fuel cost. The primary stage at 68-89oC is the exothermic dehydration of the biomass with the release of water and low-molecular-weight gases like carbon monoxide (CO) and carbon dioxide (CO2). The results from this research will be significant and helpful to develop and utilize the wastes from Dendrocalamus asper bamboo with 134.58 kJ for any renewable energy product.
... Wood and bamboo have recently been renowned in the green engineering technology industry because of their environmentally promising characteristics. They can be replaced by a natural processes, biodegradable, confine carbon from the atmosphere, low in combined energy, and create less pollution in development than concrete or steel (Falk 2009 andMahdavi et al. 2011). Bamboo is a green material that can possibly substitute the wood for reasons that, bamboo can be cropped in 3-4 years from the time of plantation as compared to timber which takes decades (Lakkad &Patel 1980 andAmada et al. 1997). ...
Article
Full-text available
Green engineering is increasingly investigated as a possibility to treat organic green material for structural applications. Dendrocalamus asper bamboo culms as green engineering materials were processed to produce composite materials using epoxy resin from a natural treatment by soaking with an average of pH 7.6 level of seawater. Mechanical properties of proposed laminated bamboo composites (LBCs) have been assessed under loading conditions and standards. The study provides a comparison of the structural performance with different conventional timbers as an avenue for application in engineering design and practices. Comparison of laminated bamboo with woods indicates that average value of 27.47 MPa and 52.59 MPa for compressive and bending strength respectively, obtained much higher allowable value and average strength, which are comparable to stiffness values of softwoods and hardwoods. However, even though the present study shows properties with higher and comparable to other composite materials, further research must be given better attention for characterization and standardization before acceptance in the marketplace as alternative green engineering material to timber and wood-based composites and other building materials for construction design, and structural elements as composite materials for engineering utilization. Nat. Env. & Poll. Tech. Website: www.neptjournal.com
... Wood is considered as the material of the future (Kuzman and Sandberg 2017;Żmijewki and Wojtowicz-Jankowska 2017), whereas has many positive characteristics from its production such as low embodied energy, low carbon impact, and sustainability (Falk 2010;Werner et al. 2010;Sneed 2017). Low weight-to-strength ratio of timber may be advantageous under collapse (Huber et al. 2018). ...
Article
Full-text available
This research identified the central hindrances found in Brazilian wooden housing scenario in the fields of finished product, producer, and sector. Thus, a questionnaire with three qualitative questions based on multiple-choice answers allowed investigating the difficulties faced by these producers in Brazil. This sector still faces obstacles in the three observed fields, especially for the negative aspects of house financing, housing technique certification, skilled hand labour, general costs incurred in local production, tax exemptions, public policies, utilization of wooden houses in public works, and other factors. These obstacles in wooden housing sector have created limitations of production potential and restrictions of its market. A current panorama from these obstacles was formed, which could contribute with sectoral development. Actions such as creation and institution of incentives and specific policies should consolidate as the main direction to reduce these difficulties faced by the wooden housing producers. **For FULL VERSION of this paper, please contact me...
... Nowadays, timber and bamboo buildings again have started gaining attention because low-carbon and ecological concepts are the new architecture tendency. Also, primary construction materials used in modern timber structures are renewable materials and are better than fossil materials such as steel and concrete in thermal performance, which is in conformity with the sustainable development principle [1,2]; thus, timber buildings have become a new development trend in recent decades. In northern America, timber buildings are already preferred in low-carbon architecture, and almost 90% of low-rise buildings are timber structures. ...
Article
Full-text available
Parallel strand bamboo (PSB) is a latest construction material; to know more about mechanical properties of PSB, 5 groups of specimens with difference only in bolt diameter were designed to study the impact of the fastener diameter on embedding strength perpendicular to grain of PSB. Based on the tested result, the feasibility for PSB of the theoretical equation in the American code and European code on embedding strength predication was assessed. A controlled displacement was used to load till specimen failure, the stress-displacement curve of all specimens was obtained in terms of the tested results, and the yielding tested strength based on 5% bolt diameter offset proposed by the American code was found. The tested results showed that the yielding strength perpendicular to grain of PSB was stable, the variable coefficient was between 5.88% and 13.34%, and the average yielding strength values were 80.84 MPa, 77.40 MPa, 76.52 MPa, 74.20 MPa, and 67.01 MPa, respectively, which decreased with the increase of bolt diameter, and the average yielding strength values are larger than the calculated results using theoretical formula. Therefore, the theoretical equation on embedding yielding strength of wood in the American code and European code applies to PSB.
... Essa hipótese foi estudada e confirmada nos trabalhos de Robertson et al. [11] e Börjesson e Gustavsson [12] que fazem as Análises de Ciclo de Vida (ACV) quantificando e comparando os impactos ambientais entre os diferentes sistemas construtivos, convencionais e em CLT. Além disso, o CLT utiliza baixa energia para sua manufatura e aplicação, [13]. ...
Article
Full-text available
RESUMO Os painéis de madeira laminada cruzada (CLT) são formados por lâminas de madeira com grandes dimensões arranjadas ortogonalmente e unidas com adesivo estrutural sob alta pressão. O sistema de laminação cruzada possibilita ao CLT trabalhar como um elemento estrutural rígido e autoportante. Além disso, são isolantes térmicos e acústicos e apresentam bom comportamento para situações de incêndio. São utilizados como elementos estruturais e de fechamento em edificações de vários pavimentos em construções pré-fabricadas e este sistema construtivo pode ser considerado mais sustentável, que gera menos impactos ao meio ambiente, frente às soluções tradicionais brasileiras. A madeira é um recurso natural renovável e quando utilizada na construção, cumpre um papel importante para o meio ambiente: armazenar o CO2 e utilizar baixa energia para sua manufatura e aplicação quando comparada aos materiais convencionais empregados na construção como o aço, o concreto e o alumínio. Para o dimensionamento dessas estruturas ainda não existe uma abordagem de cálculo universalmente aceita pelos projetistas e fabricantes de CLT. Neste trabalho, são dimensionados os painéis de CLT do tipo lajes de piso ou cobertura sujeitos à flexão a partir dos principais métodos de dimensionamento. Os resultados obtidos foram comparados e constatou-se que o método de maior precisão foi o que considerou a rigidez estrutural de todas as lâminas. A maior precisão no projeto e dimensionamento dos painéis de CLT contribui para uma engenharia sustentável, na medida em que otimiza o uso do material na estrutura.
... Also, wood material production uses less energy compared to the production of other materials such as concrete. In addition, the forest resource is renewable with good management, therefore wood is a material that does not deplete natural resources (Falk 2009). ...
Conference Paper
Over the past two decades, the construction industry has experienced a lot of positive changes in Saudi Arabia. Governments and lawmakers have come up with various regulations that govern the construction industry, such as the Saudi Building Code. These regulations have been effective in creating legal boundaries and rules for contractors and developers to abide by. However, critics and environmentalists suggest that contractors still have undertaken various activities that are of great harm to the environment. For example, wasted materials left in the surrounding area of construction job sites are a great cause of environmental pollution. Such pressure has led to the pursuit of a new trend in the construction industry known as sustainable construction. Sustainable construction entails the use of processes and materials that have little or no negative impact on the environment, and the construction of tall and complex structures that are important to accommodate the ever-growing population. In spite of the universal agreed guidelines for sustainable construction, detailed implementation methods depend on local contexts. This paper presents an initial effort in creating an ontology that describes the potential sustainable construction strategies in Saudi Arabia, to create a guidance for improving the energy efficiency of buildings in Saudi Arabia. The ontology is expected to (1) help create construction job sites that are not only environmental friendly, but also better serve the interests of all stakeholders; and (2) help reduce energy usage in buildings.
... The BEES (Building for Environmental and Economical Sustainability) software [8] is a freely available tool that assists the selection of building products with favorable performance in both environmental and economical aspects. Studies were also performed on the sustainable building materials, such as wood [9], new-type cement [10][11][12], unconventional insulation materials [13], and so on. For infrastructure, Mihyeon and Amekudz [14] reviewed sixteen sustainability initiatives for transportation systems and classified the indicators and metrics into five categories, namely economy, transportation, environment, safety and society. ...
Article
Current structural design methods mostly emphasize the short-term structural behavior while neglect the long-term performance, social effects and environmental impacts. To address these problems, the Life-Cycle Design (LCD) method considering environmental impacts and structural deterioration could be adopted within the design process to ensure that the structural performance satisfies various objectives. Due to the complexity and the long lifespan of engineering structures, as well as the lack of standardized design approach, studies and application of LCD that cover all the design objectives are limited. This paper proposes a hierarchical LCD method for concrete structures by combining traditional design with green design and other engineering aspects. The design process is divided into six levels that cover the aspects of structural safety and reliability, durability, economic efficiency, local environment, social impacts, and global environment. The proposed design method is then applied to a reinforced concrete highway bridge in marine environment for the purpose of illustration, and a comprehensive comparison between traditional design and the hierarchical LCD approach is made within six design levels. A brief discussion on the hierarchical LCD framework and the future works is presented before conclusions are made.
... Because access to nature is limited for most urban residents, it is necessary to consider using elements of nature such as wood in the indoor environment. Moreover, wood interiors have been shown to have a positive impact on residents, especially in relation to benefiting stress (Falk, 2009;Fell, 2010;Nyrud, Bringslimark, & Bysheim, 2014) and potentially restoring performance (Burnard, Tavzes, Tosˇic´, Brodnik, & Kutnar, 2015;Ulrich et al., 1991). The visual effects of wooden rooms have been shown to have lower impact on systolic blood pressure, an indicator of autonomic nervous system activation (Tsunetsugu, Miyazaki, & Sato, 2002, 2007. ...
Article
The biophilic hypothesis states that human beings have an innate connection to nature. Accordingly, previous studies have shown that natural interior design elements may influence the occupants’ cognitive performance. This study investigated the effect of wooden elements on the occupant preference and cognitive performance of 20 adults (10 females and 10 males). Participants reported increased attention and productivity in wooden rooms versus a nonwooden room and were more likely to choose one of several wooden rooms over a concrete room as their preferred work environment. Participants also performed better on neurobehavioral tests in the wooden versus nonwooden environment. Participants’ average completion times decreased on average by 16 seconds, 5 seconds, 6 seconds, 16 seconds, and 7 seconds, respectively, for tests of Visual Reaction, Continuous Operation, Stroop, Calculation, and Meaningless Picture Recognition tests in the wooden versus concrete environments. On all five tests, participants gave more correct answers in the three wooden settings than in the concrete one. These results support the biophilic hypothesis; incorporating wooden elements into interior design may improve both occupant satisfaction and cognitive performance.
... construction material. Existing studies indicate that wood has a lower embodied energy than functionally equivalent construction materials, such as concrete (Falk 2009), and a lower carbon footprint (Gustavsson et al. 2006). However, comparing the environmental performances of products requires a thorough analysis of their contribution to different impact categories (Werner and Richter 2007). ...
Article
Full-text available
Purpose Life cycle assessment (LCA) is broadly applied to assess the environmental impact of products through their life cycle. LCA of bio-based products is particularly challenging due to the uncertainties in modeling the natural biomass production process. While uncertainties related to inventory data are often addressed in LCA by performing sensitivity analyses, the sensitivity of results to LCA methodologies chosen is seldom addressed. This work investigates the influence of common methodological choices on LCA climate impact results of forestry products. Methods Performing a consequential LCA, the study compares results obtained through different choices concerning four methodological aspects: the modeling of land use change effects, the choice of climate metric for impact assessment, the choice of time horizon applied, and the completeness of the forest carbon stock modeled. Eight scenarios were tested, applied to the same case study to ensure the full comparability of the results. A dynamic life cycle inventory of annual forest biomass production and degradation was obtained through a methodology accounting dynamically for the annual carbon fluxes in a forest plot. Results and discussion The results obtained for the eight scenarios showed a great variability of the estimated climate effect, ranging from a net carbon sequestration of 24 kg CO2 equivalents to a net carbon emission of 3220 kg CO2 equivalents, though seven out of eight scenarios resulted in a net carbon emission. The results are particularly sensitive to the choice of time horizon, especially when combined with the choice of static or dynamic climate indicator and different climate metrics as GWP and GTP. The case study showed a lower variability of results to the choice of forest carbon stock compared to the effect of the other tested assumptions. Conclusions LCA results of forestry products were highly sensitive to the tested methodological choices. A description and motivation of these choices is required for a clear and critical interpretation of the results. The choice of climate indicator and TH applied depends on the goal and scope of the study and strongly affects the contribution to climate impact results of all LCA processes. Those choices need to be carefully discussed and should be in accordance with the goal of the study, since different climate metric and TH have distinct interpretations. The interpretation of different climate indicators and their time horizons should be linked with the considered endpoints of climate change.
... This method can be applied to any wood and non-wood material which require additional improvement. Bamboo is a high potential future construction material because of its strength properties and high resistance-to-weight ratio (Falk 2009). Gigantochloa scortechinii has a MOR value of 176 MPa which is equivalent to some Malaysian heavy hardwood such as resak (Vatica sp., 91–133 MPa), balau (Shorea sp., 142 MPa) and merbau (Intsia palembanica, 116 MPa). ...
Article
Full-text available
This study evaluated the mechanical properties and dimensional stability of 3-ply phenolic-treated plybamboo influenced by treatment methods, namely, impregnation and soaking for 30, 60 and 90 min. Medium molecular weight phenol formaldehyde (MMwPF) resin with 1500 g mol⁻¹ was applied to bamboo (Gigantochloa scortechinii) slivers of 2-mm thickness following resin treatments. The phenolic-treated bamboo slivers were precured at 60 °C for 6 hours, followed by hot pressing at 140 °C for 15 min to produce a 3-ply phenolic-treated plybamboo. Untreated boards were prepared using commercial phenol formaldehyde resin as binder. Use of MMwPF resin increased the density of boards. Modulus of rupture and impact resistance of the samples were significantly affected (p ≤ 0.01) by treatment methods but treatment duration did not show any significant effect. Reduced water absorption, thickness swelling and linear expansion suggested improved dimensional stability of the phenolic-treated sample. Treatment with phenolic resin markedly increased anti-shrinkage efficiency at p ≤ 0.05. Impregnation was more effective compared with soaking method.
... The timber trusses for the roof of Velodromo of Sangalhos (2009), Portugal, with a maximum span of 78.6m, is a good example of how to arrange the pieces using a classical dowel connection system without using slotted-in steel plates [102]. The reinforcement of the nodes using plywood board has now been also recuperated for short spans and an industrialized production [25]. ...
Book
Full-text available
Bridges are the most demanding of structures. They are often long-span, subject to large and variable dynamic loads, exposed to the weather, require low maintainance and, being seen as “gateway” or “landmark” structures by the public, are subject to close scrutiny. Timber bridges occupy a special place within the timber engineering community. For many professionals involved in this field, from the planning engineer, to the timber manufacturer and to the responsible for the operation and maintenance – the owner -, timber bridges represent the highest achievement in the art and science of wooden architecture and construction. Within Europe (and in the rest of the world) there are many different approaches to deal with this topic. The history of the wooden bridges has seen many stories – for example the ones old bridges which have survived for centuries, and of those in need of repair or even demolition after only a decade of being in use. The combination of large spans with heavy loads and major climatic actions on bridges is a big challenge for everybody involved in planning, constructing and maintaining these special timber structures. This requires that all effected parties have, in addition to the possibly large emotional devotion to such an object, above all, an extensive knowledge and experience in the planning, implementation and maintenance of timber bridges. Since timber bridges are not built in a dozen every day, it is important that an active exchange of knowledge between parties takes place. This is what the COST Timber Bridges Conference CTBC2014 in Biel aims to contribute to. At this conference, which is jointly supported by the COST Actions FP1004 and FP1101, young researchers as well as old hands in the field of timber bridges get the opportunity to share their own knowledge while –at the same time- learning from others. The joint participation of the two Cost Actions, FP1004 focusing on Enhamcement of mechanical properties of timber products and structures, FP1101 focusing on Assessment, Strengthening and Monitoring of existing timber Structures, ensures that a vast field of knowledge is being covered. This ranges from the enhancement of wooden materials and components for new timber bridges to the assessment, strengthening and monitoring of existing bridges, both modern and historic ones. Following the conference, in which the theoretical foundations are highlighted, a field trip and excursion to existing old and new timber bridges will provide the opportunity to learn from real cases and continue the knowledge exchange on-site. The programme of the conference is designed to stimulate and facilitate discussion from the delegates, and we hope that it will contribute to build bridges between young and old researchers, theorist and practitioners as well as between fellows from regions with high timber bridges "populations" and people coming from regions where even the term "timber bridge" sounds very strange. Besides the genuine interest for the subject, that gave us the impetous to organize this event, building these last mentioned bridges is a main goal of the COST framework. Let's go for it!
... As a building material, wood is a renewable resource that sequesters carbon during the life of the building (Falk 2009). Furthermore, wood has an excellent strength-toweight ratio and is frequently cited as having a warm, pleasing appearance (Rice, Kozak, Meitner and Cohen 2006). ...
Article
Chemical modification of wood increases decay resistance but the exact mechanisms remain poorly understood. Recently, Ringman and coauthors examined established theories addressing why modified wood has increased decay resistance and concluded that the most probable cause of inhibition and/or delay of initiation of brown-rot decay is lowering the equilibrium moisture content. In another recent study, Jakes and coauthors examined moisture-induced wood damage mechanisms, including decay and fastener corrosion, and observed that these mechanisms require chemical transport through wood cell walls. They proposed that chemical transport within wood cell walls is controlled by a moisture-induced glass transition in interconnected networks of hemicelluloses and amorphous cellulose. This paper shows how these models jointly suggest mechanisms by which wood modifications can inhibit brown-rot. Alternative mechanisms are also discussed. These models can be used to understand and further improve the performance of wood modification systems.
... Timber is undeniably a natural renewable resource and a carbon store, whose production requires small amounts of energy (Petersen and Solberg 2002;Falk 2009); therefore, its use on TCC bridge decks enhances the environmental performance when compared with concrete deck bridges. This may contribute to increasing the selection of this alternative in bridge construction. ...
Article
Over the last few years there has been a renewed interest on the use of timber-concrete composite (TCC) structures in bridge decks, possibly because of their cost competitiveness and environmental friendliness. Accordingly, this paper investigates the sustainability of TCC bridge decks under a threefold environmental, economic, and sociocultural perspective. Two different types of decks, which represent the overall characteristics of TCC bridges constructed around the world, are first described. Next, the paper presents a comparative sustainability assessment of two existing concrete bridges and their TCC deck potential alternatives (of the types previously mentioned); a lifecycle methodology, based on standards from the International Organization for Standardization (ISO) and other publications, is followed. The main conclusions are that, when compared with concrete decks, TCC solutions cause less environmental impact and are cost-competitive. Regarding sociocultural impacts, this analysis reveals the lower user-incurred costs of one of the TCC deck types.
... In order to address the mentioned problems related to non-renewable construction materials, more attention lays on engineered wood elements as bio-based, renewable, sustainable and recyclable material to replace currently used traditional materials in modern single and multistory building constructions [5]. Manufacturing of wooden-based construction materials demands less energy compared to steel and concrete and the wastes are recycable [7]. ...
Article
Full-text available
Wood impregnated with a multicomponent mixture of fatty acids as a bio-based phase change material (BPCM) to improve its thermal characteristics was studied. The studied wood/BPCM composites can be used as internal elements in buildings for energy storage. Scots pine and beech sapwood were impregnated with a multicomponent mixture of linoleic acid and coconut oil fatty acids at a ratio of 20:80. Leakage test was conducted and revealed that the maximum leakage for pine and beech were 9 and 8%, respectively. Light microscopy was employed to demonstrate the distribution of the BPCM in the wood structure. Rays in both pine and beech wood served as pathways for impregnation of the BPCM to partly fill the tracheid lumens (pine) and vessels (beech). Thermal characterization of the studied samples employed T-history and DSC methods, concluding that the impregnated wood had significant thermal mass, ability to store excessive energy in terms of latent heat and keep the temperature constant for long time. The specific heat capacity of the impregnated samples was 4–5 J g ⁻¹ K ⁻¹ i.e., higher than that of the untreated control samples of ca. 2 J g ⁻¹ K ⁻¹ . The thermal conductivity of the samples before and after the impregnation was measured using heat flow meter method and the results showed that the untreated beech wood had higher thermal conductivity compared to pine and the parameter improved when the cell lumens were filled with the BPCM. Scots pine wood with to 80% mass percentage gain (MPG) after impregnation demonstrated an increment in thermal conductivity of 33% while Scots pine and beech with 43 and 38% MPG demonstrated an increase of the conductivity with 8 and 11%, respectively.
... The timber trusses for the roof of Velodromo of Sangalhos (2009), Portugal, with a maximum span of 78.6m, is a good example of how to arrange the pieces using a classical dowel connection system without using slotted-in steel plates [102]. The reinforcement of the nodes using plywood board has now been also recuperated for short spans and an industrialized production [25]. ...
... However, environmental problems connected with FRP are gaining attention [3]. In this respect, plywood which is made of sustainable material [4] is better than FRP. The drawbacks of these materials could be lessened and plywood could be well reinforced if they are properly combined and modified into one composite material. ...
Article
Full-text available
The aim of this study was to create a reinforced composite wood-based panel that would be leaned towards the environment Plywood was used as a core material and fiber-reinforced polymer was used as a reinforcement. Conventional resin for the fiber-reinforced polymer was substituted with polyvinyl acetate (PVAC), which has several advantages, such as a lower price, easier handling, and better degradability. The second chosen component, basalt fiber, is cost attractive and environmentally friendly. The combination of one and two layers of fabric with three fiber fractions and 4 mm thick plywood was investigated. The best results were achieved with two layers of fabric and the highest fiber fraction. The improvements of the ultimate bending load and bending stiffness of the plywood in the perpendicular direction were 305% and 325%, respectively. The ultimate load and stiffness of the parallel direction were improved by 31% and 35%, respectively. However, specimens always failed in the compressional zone. The highest reinforcing effect was found with the impact test: The energy required to fracture specimens increased by 4213% and 6150% for one and two layers of fabric, respectively. In conclusion, specimens exhibited high ductility due to the PVAC and basalt fiber. The amount of work and energy required to cause fractures was extensive.
... Falk's [31] work focused on wood from the point of view of sustainability as such and its use and application in wood-based constructions. Based on the analyses presented in this work, the conclusions state that it is clear that the green building movement is here to stay and will undoubtedly grow in the future. ...
Article
Full-text available
“Ecological buildings” and “energy-efficient buildings” are concepts which we encounter on a daily basis and which define modern trends. The purpose of their design is to create an optimal thermal microclimate by means of heat flows that form within it or enter it. A balanced combination of heat flows creates suitable conditions for thermal comfort—a factor contributing to the quality of the internal environment of buildings. This research addresses the problem of heat distribution in construction materials based on wood and their thermal–technical properties in relation to the sustainability requirements for the thermal–technical properties of constructions and buildings. The research examines the structural parts of the external walls of modern log constructions. The objective of this work is to analyse the thermal–technical properties of the structural parts of modern log wood constructions in laboratory conditions and verify them against calculated values and values declared by manufacturers. This publication is also a contribution to the current needs in terms of the sustainability and internal environment quality of constructions in general. The publication is also a contribution to the current needs in the field of heating technology in terms of sustainability and the quality of internal environments.
... Material substitution: Using other sustainable basic materials such as wood in the building sector (Falk, 2009) or clinker substitutes (IEA, 2018b) can reduce the demand for emission and energyintensive basic materials like cement or steel. ...
Thesis
Full-text available
The industrial processes we have used for producing basic materials over the last centuries are unsuitable for an economy with a net-zero carbon footprint. Basic materials like steel, cement, aluminium and (petro)chemicals are the building blocks of our industrialised societies, but today their production is highly energy and emission-intensive. There is no other alternative. These industries need to decarbonise over the next decades for keeping global warming below 2°C. However, the implications of this transition for the industry, our energy systems and society are little understood. This thesis asks how this transition can take place by exploring the technical, economic, and regulatory dimensions of decarbonising the energy-intensive basic material sector. By following a multidisciplinary approach, the thesis looks upon these different dimensions separately, identifying propositions that characterise the industrial transition and help us understand its implications for our energy systems. The first part of the thesis studies technology options for climate-friendly basic material production in different industries and evaluates their cross-sectorial significance. Findings highlight the challenge of reducing emissions linked to the high thermal energy demand required to produce most basic materials and process emissions originating from the chemical transformation of naturally occurring resources to basic materials. Decarbonisation across all industries requires breakthrough technologies that are not available on a commercial scale. Today´s conventional production technologies are highly standardised. They rely primarily on fossil fuels, obtaining basic materials in high quantities while keeping energy costs low. However, climate-friendly breakthrough technologies mark a shift from fossil fuels to low-emission alternatives. Therefore, the second part of this thesis studies the functioning of future electricity markets and explores the implication of decarbonising energy systems for industrial consumers. Future energy markets should be designed to ensure the emission avoidance, affordability, and adequacy of energy for industrial consumers. Higher costs for low-emission energy sources or potentially higher energy demand to avoid emissions make climate-friendly basic material production more expensive than conventional processes. Breakthrough technologies require a regulatory framework to support the transition. The third part of this thesis demonstrates how different policies are needed to kick-start the transition, create markets for climate-friendly materials and ensure long-term climate neutrality. Finally, the last part of this thesis reflects upon the propositions that characterise the transition´s technological, economic, and regulatory dimensions and argues that models to study the transition need to incorporate the three dimensions sufficiently. Since energy-system models and bottom-up approaches are insufficient, a new sector-specific modelling approach is necessary. The thesis introduces the conceptual model TRANSid (Transition towards Industrial Decarbonisation) to address this modelling gap. It uses a simplified case study to demonstrate how the conceptual model could be translated into a mathematical formulation. The thesis concludes with various recommendations about the future research needs to study industrial decarbonisation across the technological, economic and policy dimensions.
... One of our best allies in solving the climate crisis due to its potential eco-friendly properties, wood is at the forefront of tackling European climate policy [34][35][36][37]. Furthermore, due to its significantly lower carbon footprint and potential cost-effectiveness compared with conventional materials such as reinforced concrete and steel, and numerous positive effects on the environment combined with technological advances [38][39][40][41]. Besides this, as it is well known, from an architectural point of view, wooden buildings are thought to have the potential to generate a more pleasant, warm, and natural environment. ...
Chapter
Full-text available
Finnish urban settlements are in the age of restoration, and the suburbs need improvements in Finland. In this sense, wooden facade renovation and additional floor construction are viable and sustainable solutions for this development in the Finnish context. This chapter focuses on these important applications from the Finnish residents' perspective as ecologically sound engineering solutions through a survey. In doing so, the challenges of facade renovation, as well as the benefits of additional floor construction, were presented. The main purpose of the survey was to get the opinions of the residents, find out which variables are important, make inferences for the planning and improvement of such areas, and determine what will be emphasized in the sustainable suburban development of the future. Therefore, the results were based on this empirical approach-survey-but further research such as energy analysis, wood-based facade renovation, and additional floor solutions will be done as part of other studies. It is believed that this study will contribute to the use of sustainable materials and decarbonization of buildings as well as zero energy building (nZEB) to overcome the challenges posed by climate change by the diffusion of wood in the renovation of buildings.
... The concept of eco-buildings, sound construction methods and material selection is gaining attention due to the growing concern for the environment [2][3][4] . Wood has been one of the main building materials throughout the history of mankind and is considered a renewable source [5][6][7] . Fire safety is especially important in construction, and wood is a fire hazardous material. ...
... Wood is a sustainable and renewable building material with a low carbon impact [1][2][3], favourable seismic performance [4,5] and ability to self-protect against fire [6][7][8]. These are some of the most relevant reasons to explain the steady increase in the use of this material in the construction and building sector [9]. ...
Article
In the last decades the use of wood as a construction material has been steadily increasing. Among the main reasons behind this, are its renewable resource nature and its low environmental footprint. In this context, one of the main challenges faced by engineers during the design process is the knowledge and characterization of wood’s thermo-mechanical properties. This is related to the large morphological variations present at the microstructural level, that lead to a wide scatter of the macroscopic properties. To circumvent this issue, in this work a multiscale modelling strategy based on asymptotic homogenisation is proposed. The model is based on the hierarchical nature of wood and incorporates the three material scales generally identified in soft woods: (i) the microfibril scale, (ii) the wood cell scale, and (iii) the growth ring scale. The effective thermo-mechanical macroscopic properties are obtained by sequentially applying the homogenisation procedure from the microfibril scale all the way up to the macroscopic scale. The model is employed here to investigate the thermo-mechanical response of radiata pine grown in Chile. To determine values of the microstructural parameters that yield macroscopic properties consistent with those observed experimentally, a parameter identification strategy is proposed. The latter considers four elements: an existing experimental database on timber boards density and bending tests, the multiscale model, a timber board bending test finite element model and a genetic algorithm for the optimization procedure. With the resulting microstructural parameters the model is then used to estimate the effective elastic, thermal, and thermo-mechanical properties of radiata pine wood. When compared with measured experimental data and typical experimental values found in the literature, the numerical estimates demonstrate the model predicting capabilities. The full article can be found in: https://authors.elsevier.com/a/1e7zS3O1E1MtnB
... Its economic benefit is not farfetched as it can be combined with other elements to form a composite. Its renewability will be possible if the policy of harvesting and planting is followed [26]. Fig. 1 shows recycled waste from agro-industrial waste. ...
Article
Full-text available
Most of the building ceiling tiles used today from studies, such as polyvinyl chloride (PVC) composite ceilings, cardboard, plywood, particleboard, are flame friendly. Except for asbestos, which is confirmed to emit asbestosis, cancer from asbestos; already warned by the Environmental Protection Agencies and other health standard organizations. Studies have shown inherent harmful elements associated with the use of PVC Ceiling composite, plant-based ceiling, and asbestos, which propagate noxious emission at the instance of fire; their widespread use is quite enormous. The noxious behaviour during an inferno is a representation of the elemental make-up of these ceiling materials. Moreover, their vulnerability due to emission and combustion threat call for alternative materials with eco-friendly constituents for building ceiling applications. Problems associated with these building ceilings during fire include noxious gaseous emissions; fuel for the flame from ignition from other roof frame structures; after flame effect of inhaling poisonous gasses against the recommended exposure limit of 35 ppm by the World Health Organization (WHO). Flame retardance is credited to asbestos. However, for other ceiling tiles, some of the challenges of high heat flux, high thermal conductivity, and combustibility tendencies, are still current issues. The undesirable side effects of using ceiling tiles have necessitated a replacement with suitable flame retardant and eco-friendly influences. This is made to bear by appropriate material selection and by employing industrial wastes and agricultural wastes coupled with suitable binders to solve flame propagation challenges. It is, therefore, necessary to develop a flame retardant ceiling composite that will solve the identified anomalies in the existing ceiling tiles in the market in building industries. The developed materials are tested for thermal and emission characteristics to ascertain their integrity by employing advanced test equipment. The result shows that there are low values in thermal conductivity of the developed building ceiling samples. Sample 2 has the lowest value compared to the developed and existing ceiling tiles, much < 0.0802 W/mK, which is a desirable property in ceiling application. Low thermal diffusivity is required to suppress flame propagation. This is exhibited by sample 1, with a value of 0.85 × 10⁻⁸ m²/s as the lowest among developed ceiling samples The result showed null and negligible SO2 detection for all samples. The three samples' time to attain pre-set temperature varies in the ascending order of sample 1 at 24 minutes, sample 3 at 37 minutes, and sample 2 at 42 minutes. Sample 3, 0.6Aldr0.34Cmt0.05G0.01OBS; Sample 2, 0.6Aldr0.32Cmt0.05G0.03OBS and sample 1, 0.6Aldr0.3Cmt0.05G0.05OBS are in the order in terms of safe emission characteristics while sample 2 ranks best in terms of flame retardancy. This study has established that the developed building ceiling composite material is flame retardant capable of preventing fire propagation, unlike the flammable polyvinyl chloride (PVC) ceiling composite. The developed building ceiling composite can minimize the emission of harmful elements in the make-up of the ceiling, as revealed in the results. The tiles are alternative to both noxious PVC and asbestos ceiling tiles. Oil beanstalk is a novel material introduced as a reinforcement to the developed composite. The manufacturing industries should explore materials with excellent eco-friendly flame retardant constituents to encourage sustainable building production.
... Surprisingly, there is now a silent revival of interest in wood products across several industries. This renewed interest is driven in large part by the recognition of some positive characteristics of wood as a sustainable material with low carbon impact and low embodied energy (Falk, 2009;Mustapha, 2020). A closer look at the upsurge in the popularity of wood indicates there is another contributing factor that is linked to the rise of engineered wood products. ...
Article
The mechanical and microstructural properties of medium-density fibreboards (MDFs) derived from two Malaysian wood species are investigated. Primarily, pieces of MDF derived from Merbau (Intsia bijuga) and rubberwood (Hevea brasiliensis) are studied to examine differences in tensile and flexural strengths as well as the difference in their morphological properties. Test results indicate the rubberwood-derived MDF displayed roughly 10% higher Young’s modulus and about 21% higher flexural modulus than the Merbau MDF. Examination via X-ray diffraction and scanning electron microscopy revealed distinct crystallinity and microstructural differences between both MDF samples, while Fourier transform infrared spectroscopy indicated higher lignin content in the rubberwood MDF. In contrast, the thermogravimetric analyses of both MDF samples yield relatively close thermal stability trends. Numerical simulations of the tests in ANSYS show that a bilinear isotropic hardening model could predict the load-induced stress–strain curves to within 12% deviation (in the elastic and post-elastic region).
... Moreover, thanks to its numerous positive impacts on the environment and potential cost-effectiveness compared to traditional materials such as reinforced concrete and steel, accompanied by its technological advances; wood, in the form of engineered wood products (EWPs), has come back to break into modern building utilization e.g., multi-story construction after more than a century [6][7][8]. ...
Chapter
Full-text available
Engineered wood products (EWPs) have been progressively more being utilized in the construction industry as structural materials since the 1990s. In the content of EWPs, adhesives play an important role. However, because of their petroleum-based nature, adhesives contribute to toxic gas emissions such as formaldehyde and Volatile Organic Compounds, which are detrimental to the environment. Moreover, the frequent use of adhesives can cause other critical issues in terms of sustainability, recyclability, reusability, and further machining. In addition to this, metal connectors employed in EWPs harm their end-of-life disposal, reusability, and additional processing. This chapter is concentrating on dovetail massive wood elements (DMWE) as adhesive-and metal connector-free sustainable alternatives to commonly used EWPs e.g., CLT, LVL, MHM, Glulam. The dovetail technique has been a method of joinery mostly used in wood carpentry, including furniture, cabinets, log buildings, and traditional timber-framed buildings throughout its rich history. It is believed that this chapter will contribute to the uptake of DMWE for more diverse and innovative structural applications, thus the reduction in carbon footprint by increasing the awareness and uses of DMWE in construction.
... Bamboo as a sustainable alternative is generating a lot of interest. Bamboo has similar environmental characteristics to wood (van der Lugt et al. 2006;Lee et al. 1994;Rittironk and Elnieiri,2007) Wood is promoted as renewable, biodegradable, sequestering carbon from atmosphere, low in embodied energy, and creating less pollution in production than steel or concrete (Falk 2009) Bamboo is one of the oldest building materials used by mankind (Abd. Latif et al.1993). ...
... In recent years, the use of timber in multistorey residential and commercial buildings has increased worldwide, primarily inspired by consciousness surrounding the sustainability of timber as the primary structural material [1,2]. Timber structures are generally associated with lower levels of embodied carbon due to lower emissions during the manufacturing of the timber products and the construction process. ...
Article
Full-text available
Over the last few decades, there has been growing interest in the use of low-carbon materials to reduce the environmental impacts of the construction industry. The advent of mass timber panels (MTP), such as cross laminated timber (CLT), has allowed structural engineers to specify a low-carbon material for a variety of floor design considerations. However, serviceability issues such as vibration and deflection are limiting the construction of longer span timber-only floor systems and have encouraged the development of timber-concrete composite (TCC) systems. The use of concrete would negatively impact on the carbon footprint of the TCC floor system and should be minimized. The purpose of this study was to study the impact on embodied carbon in the TCC system, when the ratio of timber and concrete was varied for specific floor spans. Two MTP products were considered, CLT and glued laminated timber (GLT). The floors were designed to satisfy structural, acoustic, and vibration criteria, and the results were presented in the form of span tables. It was found that using thicker MTP instead of adding concrete thickness to meet a specific span requirement can lead to lower embodied carbon values. Increasing concrete thickness for long-span floor systems led to a reduction in allowable floor span due to the vibration criterion being the controlling design parameter. Increasing timber thickness also resulted in higher strength and stiffness to weight ratios, which would contribute toward reducing the size of lateral load resisting systems and foundations, resulting in further reductions in the embodied carbon of the entire structure.
... As resource availability declines and resource demands increase in today's modern industrialized world, it is becoming increasingly necessary to explore opportunities for new, sustainable building materials (MAHDAVI et al 2011). Wood, for example, has recently gained popularity in the green building community because of its environmentally beneficial characteristics: wood is promoted as renewable, biodegradable, sequestering carbon from the atmosphere, low in embodied energy, and creating less pollution in production than steel or concrete (FALK 2009). Bamboo has similar environmental characteristics ( VAN DER LUGT et al. 2006;LEE et al. 1994;RITTIRONK and ELNIEIRI 2007;NATH et al. 2009). ...
... This species is characterized by its adaptation to drought and growth in a wide range of substrates. Due to this capacity for adaptation, Pinus halepensis Mill. is a pioneer species, with the ability to inhabit bare, recently exposed or burned lands, or abandoned agricultural areas [4]. In structural calculations applied to wood, the ultimate and serviceability limit states must be verified, similar to other types of materials. ...
Article
Full-text available
The mechanical behavior of test pieces extracted from two specimens of Pinus halepensis Mill., from the same geographical area and close to each other, was examined in this study. Using a methodology based on Digital Image Correlation (DIC) and implemented during compression strength testing, the modulus of elasticity in compression parallel to the grain (MOEc) was obtained. In addition, the value of compressive strength (MORc) was obtained for this type of wood. The research was complemented with a reliability study, determined using the Weibull modulus, from the MORc values. A microstructural and behavioral study of the most representative pieces after failure was also conducted to correlate breakage with the behavior of the pieces during the tests monitored by DIC, to link both studies. DIC was shown to be an ideal and low-cost technique for the determination of the studied properties, and obtained average values of MOEc of 50.72 MPa and MORc of 9693 MPa. These values represent fundamental data for design and calculations of wooden structures. A reliability value of between 11 and 12 was obtained using the Weibull modulus for this type of wood.
... Nevertheless, wood use in building remains very important. As an example, over 50% of the wood harvest is used for building construction in the USA (Falk 2009). The main reasons for building with wood are its good mechanical properties and versatility. ...
Thesis
Full-text available
The aim of this thesis was to test the possibility of using the residues and side-streams from Finnish wood and coffee industries as active ingredients in wood preservative formulations, as well as to compare their acute ecotoxicity. Pyrolysis distillates of bark from Norway spruce (Picea abies (L.) H. Karst.), silver birch (Betula pendula Roth) and European aspen (Populus tremula L.), the organic acids identified in these distillates, spent coffee extract, coffee silverskin extract, caffeine and the commercial Colatan GT10 tannin-rich extract were tested. Celcure C4 industrial copper preservative (for above ground use) and pine oil were used as industrial references. Antifungal tests against wood-decaying fungi and wood decay—mini block—tests were performed in vitro, and leaching tests of the potential preservatives from wood were performed. An acute ecotoxicity test with Aliivibrio fischeri photoluminescent bacteria was performed in order to compare the ecotoxicity of the potential bio-based preservatives with that of the industrial reference. All potential bio-based preservatives showed some activity against the fungi in the antifungal tests. The minimum inhibitory concentration of the extracts from coffee industry residues needed to inhibit completely all the wood-decaying fungi was over 1%. The pyrolysis distillates were able to inhibit most fungi at concentrations close to 1%. The organic acids and caffeine were able to inhibit wood-decaying fungi in the malt agar media at concentrations below 1%, showing that these constituents play a significant role in the antifungal activity of the tested distillates and extracts. However, when the potential bio-based preservatives and their constituents were tested in the wood decay tests, none of them performed efficiently as wood preservatives. The acute ecotoxicity test showed that most of the potential bio-based preservatives had low ecotoxicity, but one of the distillates exhibited IC20 of 0.02 mg/L and IC50 of 0.2 mg/L, a much higher ecotoxicity than Celcure C4, which had IC20 and IC50 values of 12 mg/L and 19 mg/L respectively. This shows that we must test the ecotoxicity of all potential antifungals before proposing them as possible wood preservatives, to ensure that new solutions are not as harmful to the environment as the present ones. It can be concluded that some of the constituents of the potential bio-based preservatives act as antifungals against wood-decaying fungi and could be included in wood preservative formulations, but their performance alone is insufficient to function as wood preservatives.
... Wood is an excellent and widely used sustainable building material for many products in the building industry and in furniture construction [1]. However, when exposed to outdoor conditions, wood surfaces are prone to degradation under solar ultraviolet (UV) radiation, leading to an alteration and discoloration of the surfaces, which in turn affects the aesthetic appearance [2,3]. ...
Article
Full-text available
In the present work, the solution precursor plasma spray (SPPS) process was used to deposit zinc oxide (ZnO) coatings on wood surfaces using zinc nitrate solution as precursor to improve the hydrophobicity and the color stability of European beech wood under exposure to ultraviolet (UV) light. The surface morphology and topography of the wood samples and the coatings were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The formation of ZnO was detected with the help of X-ray photoelectron spectroscopy (XPS) and by Fourier transform infrared (FTIR) spectroscopy. The FTIR spectra of the coated samples showed the typical Zn–O band at 445 cm−1. According to the XPS analysis, the coatings consist of two different Zn-containing species: ZnO and Zn(OH)2. Variation of the deposition parameters showed that the most significant parameters affecting the microstructure of the coating were the solution concentration, the deposition scan speed, and carrier gas flow rate. The wettability behaviors of the coated wood were evaluated by measuring the water contact angle (WCA). The coatings that completely covered the wood substrates showed hydrophobic behaviors. UV-protection of wood surfaces after an artificial UV light irradiation was evaluated by color measurements and FTIR spectroscopy. The ZnO-coated wood surfaces were more resistant to color change during UV radiation exposure. The total color change decreased up to 60%. Additionally, the FTIR spectra showed that the wood surfaces coated with ZnO had more stability. The carbonyl groups formation and C=C-bonds consumption were significantly lower.
... Compared to other wall materials, wood is more sus-tainable because it can be renewed through good wood processing man-agement. Wood has the lowest carbon emission value compared to other materials (Falk, 2009). The use of wood as a wall material can also minimize the resulting carbon emissions. ...
Article
Full-text available
Brick debris that makes up the majority of construction waste has not received proper waste disposal in Indonesia. On the other hand, brick debris could be potentially reused as non-structural building materials to reduce its negative impact on the environment. This study aims to test the effectiveness of soundproofing on recycled brick debris. The soundproof test was carried out on brick debris in the form of fine and coarse grains. The simulation box is then used as a support for the brickwork material and then the box is exposed to a sound source with a certain level of noise that is considered disturbing human comfort. Noise level measurements are made in the outside and inside the box. These measurements are tabulated and then analyzed to see the success of the two aggregates in reducing noise. Basically, the brickwork material has succeeded in becoming a recycled building material that can absorb noise, although further research must be carried out to be able to state that this material is truly ready to be used as an alternative building material with good acoustic capabilities.
... Kayu merupakan bahan bangunan yang paling banyak digunakan karena karakteristiknya yang cocok untuk berbagai penggunaan dan merupakan bahan alam yang bisa diperbaharui. Manajemen hutan dan praktek pemanenan secara lestari dapat menjamin ketersediaan sumber kayu yang berkelanjutan (Falk, 2009). Kayu sebagai bahan bangunan memiliki banyak keunggulan dibanding bahan lainnya, namun juga memiliki kelemahan, diantaranya adalah dapat terbakar, dapat menyusut, dan adanya variasi sifat dalam jenis yang sama, bahkan dalam batang pohon yang sama (Aghayere dan Vigil, 2007). ...
Article
Full-text available
Penggunaan kayu dari hutan rakyat untuk bangunan dan furnitur semakin banyak. Oleh karena itu, penelitian ini bertujuan untuk mengevaluasi sifat fisik dan mekanik kayu setelah uji biodeteriorasi alami tanpa menyentuh tanah di empat kota berbeda di bagian Barat Pulau Jawa. Kayu yang digunakan dalam penelitian ini sengon, nangka, mangium, mahoni dan kamper. Uji biodeteriorasi kayu tidak menyentuh tanah dilakukan di Bogor, Tanjung Priok, Lembang, dan Serang. Sifat fisik dan mekanik kayu diuji setelah uji lapang biodeteriorasi tersebut. Hasil penelitian menunjukkan bahwa penurunan berat kayu, berat jenis, modulus elastisitas dan modulus patah dari contoh uji kayu bervariasi di antara berbagai jenis kayu dan tempat uji. Degradasi tertinggi terjadi pada kayu sengon, sedangkan degradasi kayu mangium dan mahoni lebih tinggi daripada kayu nangka dan kamper. Sifat fisik dan mekanik kayu yang diuji di Bogor yang bercurah hujan tinggi dan bersuhu hangat lebih buruk daripada kayu yang diuji di tempat-tempat lainnya.
... On the other hand, environmental concerns such as global warming and overuse of natural resources have attracted many countries towards applying green and renewable resources. One of the sustainable solutions to deal with the habitation of urban population is to build dwellings from wooden materials harvested from sustainably managed forests [1]. In countries like Sweden, with large forest area, there is great potential to increase the use of wood in multistorey buildings. ...
Thesis
Full-text available
In recent years there has been a growing interest for building lightweight multistorey wooden residential buildings in countries like Sweden with large and renewable forests. While positive aspects of these buildings, such as sustainability, ease of construction and lightness, motivate building more in wood, poor acoustic performance is a risk which concerns the wooden-building industry. Low-frequency impact sound from walking of the neighbors upstairs is the main source of complaints about the acoustic performance of these buildings. The disturbance caused by walking sounds, transmitted through lightweight wooden floors, results in acoustic discomfort and impairs the perceived quality of the building; sometimes even when the building has fulfilled an acoustic class higher than minimum requirement, according to the national standard on sound classification and its single number ratings. The standard methods for objective evaluation of impact sound insulation of floors cannot predict, at a satisfactory level, the walking sound annoyance that the inhabitants of wooden buildings experience. This causes an uncertainty about the resulting perceived quality of these buildings, which greatly concerns the building manufacturers and demotivates them from choosing lightweight wooden elements over heavyweight building materials such as concrete. This uncertainty can be overcome by evaluating the perceived acoustic quality of the building prior to its construction. One solution is to build test houses where the subjective acoustic performance of floor samples can be evaluated in advance to the building construction. However, building a test house is expensive; besides, for evaluating the effect of every design modification on the experienced acoustic comfort of the building, a real floor sample has to be built and installed in the house, which would be timeconsuming and costly. An alternative solution is to use virtual acoustic test facilities. In this thesis a virtual design studio for impact sound is developed. It is a tool that facilitates creating and listening to the acoustic field generated by impact forces such as footsteps on lightweight floors. It also provides the possibility to evaluate the acoustic performance of floor elements in an early design phase, and to investigate the correlation between design parameters and the perceived impact sound insulation of the floor. The tool is demonstrated and a very first listening test shows that one can obtain results which are in good agreement with the results in literature. Loudness, reverberation and thumping are shown to influence the annoyance. It is also shown that there is a difference in judgement of walking sounds by persons who have experience with lightweight floors at home and by those who do not have that experience.
... Due to the increasing concern for the environment, the concept of green buildings, sustainable construction methods and materials, has been gathering attention (Bauer et al., 2007;Hwang and Tan, 2012;Spiegel and Meadows, 2010;Wu et al., 2005). Wood has been one of the major construction materials throughout human history and is considered to be renewable and sustainable (Herbert, 1993;Falk, 2009;Sathre and Gustavsson, 2009;Gustavsson et al., 2010;Hossainiet al., 2015;Knowles et al., 2011) with certain limitations. In construction, fire safety is one of concern, and wood is a fire-prone material. ...
Article
Due to the increased concern for the environment, sustainable construction materials are getting increased attention. Wood is considered a renewable, sustainable construction material. The problem with wood is that it is a fire-prone material. With an increasing number of wildland-urban interface (WUI) fires recently, it is important to consider that wood buildings are in danger to be ignited as well as may produce new sources of ignition due to firebrand production. Experiments were performed to investigate cedar roof covering effects of firebrand production from roof assemblies. Two wind speeds, 6 m/s and 8 m/s were selected for this experiment for a comparison with literature. The wood materials used were untreated cedar shingles, untreated cedar shakes, fire retardant cedar shingles and fire retardant cedar shakes. The roof assembly with fire retardant cedar shakes applied produced little or no firebrands under both wind speeds tested. Roof coverings fitted with cedar siding produced more variety of firebrands compared to only base sheathing materials. The mass and the projected area of firebrands were found to have a linear relationship. The firebrand coefficient was used for comparison. With attendant increase in wind speed, the firebrand coefficient increased in this study.
Article
Full-text available
The Sudanese housing policies encompass two main types of programs. The first one addresses the needs of all sectors of the population for the provision of plots through site and services schemes. The second type provides small built core units (Incremental housing) for the low-income groups. The aim of the paper is to review the provision of sustainable low-income housing in research and practice. The research selected some low-cost housing studies to represent research efforts and some low-cost housing constructed projects to represent the practice, these projects were constructed in different periods of time e.g. New Duim project _1949, El shabiya project_1963, Al Iskan Project _1975 and state fund projects _2001. The analysis focused on three parameters: the scope of the project, the design of the core unit and the construction including building materials and technologies, these parameters are discussed comparing research efforts and the practice. The research found that studies presented proposals for housing clusters provided good ventilation and simple design of the plots with direct access for cars and savings on sewage network. Old constructed projects had comprehensive approach including socio-_economic surveys of the intended inhabitants, while new constructed projects put more emphasis on quantities of built units than on quality of housing. Research studies proposed cheap building materials and technologies which is more sustainable than the expensive imported materials used in new constructed projects. The research identified the introduction of mixed housing of different income levels in new constructed projects that guaranteed social sustainability.
Conference Paper
Full-text available
RESUMO O objetivo do trabalho é a comparação de um projeto padrão de um conjunto habitacional de baixa renda do programa MCMV construído em alvenaria convencional quanto à eficiência energética de sua envoltória comparado ao projeto utilizando painéis de madeira nas paredes de fechamento da edificação (considerada uma solução construtiva mais sustentável). Aplicou-se o Método Prescritivo para etiquetagem do sistema de envoltórias com base no Regulamento Técnico da Qualidade do Nível de Eficiência Energética de Edificações Residenciais – RTQ-R, avaliando o desempenho de uma unidade habitacional. Os resultados do trabalho para as paredes em alvenaria demonstraram que o nível de eficiência energética obtido para a Unidade Habitacional foi nível B, tendo sido este considerado satisfatório para este tipo de empreendimento popular. Para o sistema construtivo wood frame obteve-se o nível C devido ao não cumprimento do pré-requisito da relativo à Capacidade Térmica. No entanto este sistema apresentou melhor desempenho tanto para verão quanto para inverno se comparado ao sistema de alvenaria. Recomendam-se, portanto, estudos mais aprofundados para a determinação da sua possível utilização no projeto estudado através de simulação computacional. Palavras-chave: Eficiência energética. RTQ-R. painel de madeira. wood frame. ABSTRACT The aim of the work is to compare the energy efficiency level obtained by the envelope of a standard low-income housing project of the Brazilian government housing program built in conventional masonry with the use of wood panels walls (considered to be a more sustainable constructive solution). The Prescriptive Method for labeling the envelope based on the Technical Quality Regulation for the Level of Energy Efficiency of Residential Buildings-RTQ-R, was applied. The results for the prototype in masonry walls pointed to a B level of energy efficiency which was considered to be satisfactory for this type of popular housing. For the wood frame system a level C was obtained because one of the prerequisites was not fulfilled, but presented a better performance both for summer and winter when compared to the walls built in masonry. The study recommends further studies to determine if it is possible to use the system in this Bioclimatic Zone trough computer simulations.
Thesis
The depletion of the non-renewable sources of energy and materials, also known as fossil fuels, is an issue well known nowadays. Thereby, the replacement of these sources of energy and materials by others of renewable nature has become a crucial point to ensure the sustainability of the current production system. In this respect, focusing more specifically in the field of materials, solid-wood and wood-based products play currently a significant role in buildings and interior fittings due to their structural, mechanical and environmental properties. However, wood is also known for being vulnerable against different agents, e.g. fire exposure. In this context, the development of state-of- the-art fireproofing treatments for wood and wood-based products has turned into a subject of considerable importance. Within the different existing methods, the employment of intumescent coatings is considered the most practical and efficient one for the protection of wood against fire. This type of coatings are products, which are generally based on synthetic resins at the industrial level. Among the resins available in the market, the phenolic resins are one of the most utilized. Nevertheless, their main disadvantage is that they are produced based on non-renewable compounds such as phenol and formaldehyde. Moreover, these compounds are highly toxic for human health. Consequently, the substitution of these constituents by others of renewable nature presents a great relevance. Lignin and tannins are two families of polyphenolic compounds widely abundant in nature. Thus, the replacement of phenol and formaldehyde by these types of compound would allow the synthesis of biosourced phenolic resins, environmentally friendly and with properties similar to those of the products existing in the market. Thereby, phenol was substituted by wood derived products such as lignin and tannins, which were obtained from agroforestal residues. On the other side, glyoxal (nontoxic aldehyde) was used instead formaldehyde. The enhancement of the thermal properties of the coating was achieved by introducing an inorganic phase into the polymeric matrix. For this purpose, natural flame-retardants like montmorillonite or silicates in nanoscale were implemented.Different formulation of the resins were tested as wood coating to assess their compatibility with wood and therefore select the one with the better performance. Several analyses were carried out on the coated-wood samples to evaluate the protection of wood against fire. On the one hand, it was seen a reduction of the heat released during combustion. On the other hand, the mass loss experienced during fire exposure was diminished and the flame propagation was delayed as well. These results were more notable in the hardwood species compared to softwood.
Conference Paper
Full-text available
The Sudanese housing policies encompass two main types of programs. The first one addresses the needs of all sectors of the population for the provision of plots through site and services schemes. The second type provides small built core units (Incremental housing) for the low-income groups. The aim of the paper is to examine the evolution of sustainable design of the core units built by the public sector for low-income families. The research selected some low-cost housing projects provided in different periods of time e.g. Duim project _1949, El shabiya project_1963, Al Iskan Project _1975 and state fund projects _2001 as case studied. The analysis focused on four parameters: the size of the project, the target group of inhabitants, the design of the core unit and the construction including building materials and technologies, these parameters are compared to U.N. Habitat principles of sustainable housing. The research found that old projects had comprehensive approach including socio-_economic surveys of the intended inhabitants, while new projects put more emphasis on quantities of built units than on quality of housing. Former projects used cheap traditional building materials and technologies which is more sustainable than the expensive imported materials used in new projects. The research identified the introduction of mixed housing of different income levels in new projects that guaranteed social sustainability.
Article
The Architecture Engineering and Construction (AEC) industry is increasingly called upon to adopt more efficient methods. While modular volumetric components and conventional construction techniques have been compared, the evaluation of alternative modular but non-volumetric strategies to improve construction efficiency have attracted less research attention. We report on the development of a semi-modular flexible solution for a residential bathroom “wet” wall, using Design for Manufacture and Assembly (DfMA) principles on a selected case study in Melbourne, Australia. The research findings, validated through the case study, offer savings and efficiencies over conventional construction in terms of time, labour, and materials.
Article
Full-text available
To battle climate change, the search for sustainable solutions and the reduction of environmental impacts are activities that must be pursued in all areas of human life. This study aimed to conduct a Life Cycle Evaluation of the environmental aspects and potential benefits associated with two different innovative adaptations to a sauna bath. The first adaptation is related to the selection of wooden materials for the bath’s interior construction; the second is related to the source of thermal energy. For the selection of wooden materials, experiments were performed to evaluate a graphene coating and its capacity to increase the durability of wooden materials. For the thermal energy source, a solar air heater was experimentally assessed to confirm its capacity to supply the thermal energy required to operate the sauna bath. Finally, the material selection and the heating operation were integrated in a Life Cycle Impact Assessment, contrasting two scenarios: “business as usual sauna bath” and “sustainable sauna bath.” The findings showed a significant reduction of around 61% of total emissions from the application of a solar air heater and wooden materials treated with a graphene coating. At the end of this study, “human well-being,” “ecosystems,” and “resources” were expressed in monetary values to assess the impact of the above practices in a sauna bath.
Article
Engineered bamboo, produced through the technique of gluing and reconstituting, has better mechanical properties than round bamboo and some wood products. This paper studies the flexural performance of laminated beams produced with timber and engineered bamboo. The six-layer beams were made from Douglas fir, spruce, bamboo scrimber and laminated bamboo, or a combination of these. It is confirmed that glued-laminated wood beams produced with wood of weak strength, like spruce, can be strengthened by gluing engineered bamboo lumbers on the outer faces, thus achieving better utilization of the fast growing economic wood species. Flexural failure of the laminated beams was primarily triggered by tensile fracture of the bottom fiber in mid-span, followed by horizontal tearing beside the broken surface. No relative slip between layers was observed before failure, therefore the flexural capacity of the laminated beams can be predicted using equilibrium and compatibility conditions according to the plane section assumption.
Article
Full-text available
Knowledge of carbon exchange between the atmosphere, land and the oceans is important, given that the terrestrial and marine environments are currently absorbing about half of the carbon dioxide that is emitted by fossil-fuel combustion. This carbon uptake is therefore limiting the extent of atmospheric and climatic change, but its long-term nature remains uncertain. Here we provide an overview of the current state of knowledge of global and regional patterns of carbon exchange by terrestrial ecosystems. Atmospheric carbon dioxide and oxygen data confirm that the terrestrial biosphere was largely neutral with respect to net carbon exchange during the 1980s, but became a net carbon sink in the 1990s. This recent sink can be largely attributed to northern extratropical areas, and is roughly split between North America and Eurasia. Tropical land areas, however, were approximately in balance with respect to carbon exchange, implying a carbon sink that offset emissions due to tropical deforestation. The evolution of the terrestrial carbon sink is largely the result of changes in land use over time, such as regrowth on abandoned agricultural land and fire prevention, in addition to responses to environmental changes, such as longer growing seasons, and fertilization by carbon dioxide and nitrogen. Nevertheless, there remain considerable uncertainties as to the magnitude of the sink in different regions and the contribution of different processes.
Article
Full-text available
Policymakers, program managers, and landowners need information about net terrestrial carbon sequestration in forests, croplands, grasslands, and shrublands to understand the cumulative effects of carbon trading programs, expanding biofuels production, and changing environmental conditions in addition to agricultural and forestry uses. Objective information systems that establish credible baselines and track changes in carbon storage can provide the accountability needed for carbon trading programs to achieve durable carbon sequestration and for biofuels initiatives to reduce net greenhouse gas emissions. A multi-sector stakeholder design process was used to produce a new indicator for the 2008 State of the Nation's Ecosystems report that presents metrics of carbon storage for major ecosystem types, specifically change in the amount of carbon gained or lost over time and the amount of carbon stored per unit area (carbon density). These metrics have been developed for national scale use, but are suitable for adaptation to multiple scales such as individual farm and forest parcels, carbon offset markets and integrated national and international assessments. To acquire the data necessary for a complete understanding of how much, and where, carbon is gained or lost by U.S. ecosystems, expansion and integration of monitoring programs will be required.
Article
This paper presents the Life-Cycle Assessment (LCA) of alternative building materials from forest resource regeneration or mineral extraction through product manufacturing, the assembly of products in constructing a residential home, occupancy and home repairs, and the eventual disposal or recycle. A unique feature of this study's LCA framework is that temporal distribution of events and associated environmental effects during the seed to demolition life cycle were considered by extending the scope to include forest growth through to demolition of the builidng. Our approach was to first conduct LCIs that quantified the energy, resource use, and emissions associated with a particular product, service, or activity. We followed this activity with the assessment of the house, and investigated the potential environmental consequences of energy and resource consumption and waste emissions. Finally we identified improvement opportunities for future research.
Criterion 5 Contribution of Forest Ecosystems to the Total Global Carbon Budget, Including Absorption and Release of Carbon In: Data report: A supplement to the national report on sustainable forests –
  • L Heath
  • J Smith
Heath, L. and J. Smith. 2004. Criterion 5, Indicator 27: Contribution of Forest Ecosystems to the Total Global Carbon Budget, Including Absorption and Release of Carbon. In: Data report: A supplement to the national report on sustainable forests – 2003, D. Darr, coord. FS-766A. USDA, Washington, DC. p. 7.
Beginners Guide to Third-Party Forest Certification: Shining a Light on the Canadian Standards Association (CSA) Report of the Dovetail Partners
  • K Fernholz
  • J Howe
  • P Guillery
  • J Bowyer
Fernholz, K., J. Howe, P. Guillery, and J. Bowyer. 2005. Beginners Guide to Third-Party Forest Certification: Shining a Light on the Canadian Standards Association (CSA). Report of the Dovetail Partners, Inc. www.dovetailinc.org.
EPA) Energy Trends in Selected Manufacturing Sectors: Opportunities and Challenges for Environmentally Preferable Energy Outcomes
Environmental Protection Agency (EPA). 2007. Energy Trends in Selected Manufacturing Sectors: Opportunities and Challenges for Environmentally Preferable Energy Outcomes.
Biomass Energy Consumption in the Forest Products Industry
  • B Murray
  • R Nicholson
  • M Ross
  • T Holloway
  • S Patil
Murray, B., R. Nicholson, M. Ross, T. Holloway, and S. Patil. 2006. Biomass Energy Consumption in the Forest Products Industry. U.S. Dept. of Energy, RTI International.
Carbon in U.S. Forests and Wood Products State by State Estimates
  • R Birdsey
  • G Lewis
Birdsey, R. and G. Lewis. 2002. Carbon in U.S. Forests and Wood Products, 1987–1997: State by State Estimates. USDA Forest Service, General Technical Report GTR-NE-310.
United Nations Economic Commission for Europe Forest Products Annual Market Review
United Nations Economic Commission for Europe (UNECE). 2008. United Nations Economic Commission for Europe/Food and Agriculture Organization of the United Nations, Forest Products Annual Market Review 2007–2008. www.unece.org/ trade/timber.
Wood Products and Carbon Protocols: Carbon Storage and Low Energy Intensity Should be Considered
  • J Bowyer
  • S Bratkovich
  • A Lindberg
  • K Fernholz
Bowyer, J., S. Bratkovich, A. Lindberg, and K. Fernholz. 2008. Wood Products and Carbon Protocols: Carbon Storage and Low Energy Intensity Should be Considered. Report of the Dovetail Partners, Inc. www.dovetailinc.org.
Contribution of Forest Products to the Global Carbon Budget In: Data report: A supplement to the national report on sustainable forests –
  • L Heath
  • K Skog
Heath, L. and K. Skog. 2004. Criterion 5, Indicator 28: Contribution of Forest Products to the Global Carbon Budget. In: Data report: A supplement to the national report on sustainable forests – 2003, D. Darr, coord. FS-766A. USDA, Washington, DC. p. 10.
Beginners Guide to Third-Party Forest Certification: Shining a Light on the Programme for the Endorsement of Forest Certification schemes (PEFC) Report of the Dovetail Partners
  • K Fernholz
  • J Howe
  • P Guillery
  • J Bowyer
Fernholz, K., J. Howe, P. Guillery, and J. Bowyer. 2004. Beginners Guide to Third-Party Forest Certification: Shining a Light on the Programme for the Endorsement of Forest Certification schemes (PEFC). Report of the Dovetail Partners, Inc. www.dovetailinc.org.