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The benefits of aluminum lamination in improving the physical and mechanical properties of wood-based composites is now well documented. This paper shows the contribution of life cycle assessment (LCA) as a tool to assess and compare the environmental footprint in the development of laminated panels. SimaPro 9.0 software, using Ecoinvent database was used to analyze the environmental impacts associated with the manufacturing of wood aluminum-laminated (WAL) panels and aluminum honeycomb panel (AHP). The impact 2002+ method was used to estimate environmental impacts. The LCA results show that the WAL panels manufacturing had a lower environmental impact than AHP manufacturing. In term of product, wood-based composites were the best choice as a core in laminated panel manufacturing. Wood-based composite manufacturing showed environmental advantages in all damage categories except in ecosystem quality. Aluminum alloy sheets manufacturing played an important role in the generation of environmental impacts for laminated panel development.

Wood cladding is used in the residential market. However, the use of wood cladding in nonresidential and large multi-residential projects can sometimes be difficult. This paper highlights the barriers to the use of this material and draws recommendations to overcome them. A triangulation approach was used to enhance the validity of the findings with a deep literature review, interviews with different stakeholders, and analysis of several websites. The cross-compared analyses indicated that four main obstacles have hampered the use of wood cladding in non-residential projects. In order of importance, these obstacles are the recurring maintenance needed, restricting regulations (building code fire-safety and architecture implementation), appearance issues, and technical considerations regarding detailing and installation. To overcome the barriers of wood use in the non-residential market, three development axes are proposed based on communication with stakeholders, product adaptation for non-residential markets, and new product development with regards to product maintenance performance. These recommendations can guide manufacturers in adapting their product development strategies.

High-density wood is required in wood flooring, especially in engineered wood flooring (EWF) designed for heavy-duty applications. However, high-density wood resources are limited and their cost is high. A densification treatment makes it possible for low- or moderate-density woods to replace harder species by modifying them into high-performance and high-value products, such as engineered wood flooring for heavy-duty applications. The general objective of this study was to develop a prototype of engineered wood flooring using sugar maple hygro-thermally densified surface layers. The results showed that thin sugar maple lumber densified at 200 °C under the combined effects of steam, heat, and pressure with a heat-resistant fabric had great potential for the manufacturing of engineered wood flooring for heavy-duty use. As a result of treatment, it acquired high density, improved mechanical properties, and it had a relatively high dimensional stability and an attractive color. Tests in conditioning rooms showed that the EWF with a densified sugar maple (Acer saccharum March.) surface layer presented the lowest amplitude distortion between the dry and humid conditions compared with the standard EWF (0.15 mm vs. 0.17mm and 0.25 mm).

Engineered wood flooring (EWF) is a multilayer composite flooring product. The cross layered structure is designed to give good dimensional stability to the EWF under changing environmental conditions. However, during winter season in North America, the indoor relative humidity could decrease dramatically and generate an important cupping deformation. The main objective of this study was to characterize the interlaminar stresses (σ 33, σ 13 and σ 23) distribution at free-edges in EWF made with an OSB substrate. A three-dimensional (3D) finite element model was used to predict the cupping deformation and to characterize stresses developed in the EWF. The finite element model is based on an unsteady-state moisture transfer equation, a mechanical equilibrium equation and an elastic constitutive law. The physical and mechanical properties of OSB substrate were experimentally determined as a function of the density and moisture content. The simulated EWF deformations were compared against the laboratory observations. For both simulation and experimental results, the cupping deformation of EWF was induced by varying the ambient relative humidity from 50 to 20% at 20°C. A good agreement has been found between the numerical and experimental EWF cupping deformation. The stress distribution fields generated by the model correspond to the delaminations observed on the OSB substrate in the climate room. Delamination in EWF can occur principally under the action of the tension stress or a combination of tension and shear stresses. Finally, simulated results show that the levels of interlaminar stresses are maximal near the free-edges of EWF strips.

Oriented strand board (OSB) is a commodity product subject to market fluctuation. Development of a specialty OSB could lead to a better, and more stable, market segment for OSB. It was demonstrated in a previous study (Barbuta et al. in Eur. J. Wood Prod. 2010), that OSB may be designed to obtain a high bending modulus of elasticity in the parallel direction, close to Baltic Birch Plywood (BBP) in its strongest direction. This study focused on the use of such specialty OSB in the manufacturing of engineered wood flooring (EWF) prototypes, a product that widely uses BBP as substrate in Canada. The performance of these two prototypes (aspen/birch and ponderosa pine) was studied. Five types of substrates: BBP, sheathing OSB, web stock OSB and the two specialty OSB prototypes were used to manufacture EWF. A 3-mm thick sugar maple plank was selected as the surface layer for all constructions. A polyvinyl acetate (PVA) type I adhesive was used to bond the components. The tests in conditioning rooms showed that BBP substrate constructions present the lowest distortion between humid and dry conditions as well as aspen/birch specialty OSB, according to ANOVA. The construction with OSB sheathing, OSB web stock and ponderosa pine OSB substrates showed higher distortion. The PVA type I adhesive led to weak bonding with high-density OSB surface. The results of this study demonstrate the potential of OSB panels to be used as substrate for EWF.

The purpose of this study was to develop speciality oriented strand board (OSB) with high stiffness for use in products such as engineered wood flooring (EWF). Three-layer oriented strand boards were manufactured from two feedstocks of strands: a mixture of 90% aspen (Populus tremuloides) and 10% of paper birch (Betula papyrifera), and 100% of small diameter ponderosa pine logs (Pinus ponderosa). The OSB panels were manufactured under a factorial design of three resin contents, two density profiles, and three weight ratios for the face and core layers. Tests to determine density, bending modulus of elasticity (MOE), internal bond (IB) and thickness swelling (TS) were performed according to ASTM standard D 1037-06a. The results showed that the higher values of bending MOE for panels made from aspen/birch mixture and ponderosa pine, 8190 and 9050 MPa, respectively, were obtained for the same combination of factors. Such high bending MOE values are very close to Baltic birch (Betula pendula) plywood, a product known for its high stiffness. The effect of resin content on IB is more pronounced for panels made from ponderosa pine than panels made from the aspen/birch mixture. Thickness swelling of panels made from ponderosa pine strands is higher than thickness swelling of panels made from a mixture of aspen and birch strands. The results indicate the potential to tailor an OSB for a specific application such as EWF.

This study investigated the effect of the relative humidity (RH) and density of unidirectional oriented strand board (OSB) on parallel, perpendicular and through-the-thickness elastic modulus (E1, E2 and E3) and interlaminar shear modulus (G13 and G23). The relationships between these parameters and density were determined on unidirectional OSB panels with a flat density profile. The target densities were: 550 kg/m3, 700 kg/m3 and 850 kg/m3. Two RH levels at a constant temperature of 20°C were used to determine relationships between OSB mechanical properties and moisture content (MC). The analysis of variance (ANOVA) indicated that only density had a significant effect on the mechanical properties considered. Even though the effect of RH was not significant, a trend could be observed. Oriented strand board E1, E2, E3, G13 and G23, increased with an increase in density and decreased with an increase in RH. Finally, a regression procedure was used to determine the linear or quadratic equation necessary to predict the mechanical properties of the OSB panels as a function of density. A positive correlation was observed between the unidirectional OSB properties considered and density. These data will support the modeling of the hygromechanical behaviour of the OSB used as component in wood composite constructions.