Exterior wood coatings are exposed to UV light, moisture, temperature changes, etc. Most of them, even if they protect the wood for a certain period of time, will eventually fade, peel and wood will have to be resurfaced and refinished at some point. Water-based acrylic coatings are now standard for exterior wood products. These coatings are cheap, show a good adhesion on most wood substrates and possess a good mechanical resistance. Unfortunately, acrylics contain chemical functions, esters, which are sensitive to UV light and temperature degradation. Strategies have been developed to limit the degradation of acrylics. Until now, none of them have shown exceptional performance.
Polyvinylidene (PVDF)-acrylic coatings are well known for their good chemical resistance and weatherability. They have shown outstanding performance as architectural coatings. They can sustain more than 30 years of outdoor exposure without color or gloss changes. Until now, fluoropolymer coatings have been used only on metal substrates, the reason being that fluoropolymer solvent-based coatings need high baking temperature. Now that water-based PVDF-acrylic coatings can be prepared, these coatings could be used on heat-sensitive substrates, such as wood, as they can be dried at room temperature.
In this project, water-based semi-transparent and opaque PVDF-acrylic coatings have been prepared and applied on white pine and black spruce panels. Accelerated and natural weathering experiments were performed in order to compare the performance of these coatings. Results revealed that PVDF-acrylic coatings show a much better color retention than the acrylics. ATR-FTIR and XPS experiments revealed that chemical degradation is much lower for PVDF-acrylic coatings, which could explain the good color retention.
The addition of flame retardants and nanoparticles to a commercial lacquer coating are shown to improve its flame retardant performance in the ASTM D3806-98 standard test method for small-scale evaluation of fire-retardant paints. A water-based, clear, acrylic lacquer, commonly used for furniture and kitchen cabinets, was selected as the control coating. Two types of flame retardants were investigated: one type of ammonium phosphate and a mineral-based flame retardant, along with eight types of nanoparticles including two nanoclays. Prior to the flame retardant performance test of the coating formulations, their physical and morphological properties were determined. The pH of all coating formulations tested was measured to be within the acceptable range for finishes used in industry. In measurements of their opacity with a spectrophotometer, all coating formulations were shown to maintain the transparency of the lacquer. Coating formulations containing nanoparticles were characterized by transmission electron microscope (TEM) and confirmed to be well distributed. Similarly, the coatings with added flame retardants were shown to be well dispersed with a grind gage. Thermal stability and decomposition kinetics of the different coating formulations were analyzed by the thermogravimetry (TG) method. With the ASTM D3806-98 standard tests, flame advance, the weight of the panel consumed, char index, and insulation value were measured. The results showed that with the addition of 5% of nanoparticles into the lacquer improved flame retardant properties were obtained. However the nanoparticles’ effect in reducing flame advance for the coating was not as significant as the flame retardants. Of the nanoparticles tested, nanoclay, nanosilica and titanium oxide showed the best improvement. It was 15%, 13% and 13% respectively. Some of the nanoparticles, especially alumina ceramic, 35% improvement and organo-nanoclay, 24% improvement, had considerable effect on the char index value of the lacquer. Coating formulations containing both flame retardants and nanoparticles were investigated for any synergies they may induce when used together and shown to further reduce panel consumption when exposed to a flame. When nanoparticles were combined with flame retardants in the coating, the char index value was reduced further in the range of 14% to 20% for the combinations of aluminum hydroxide with nano-clays. TGA results showed that the main decomposition peak of the lacquer was shifted to the higher temperatures, about 40-50 ºC by the addition of the flame retardants.
A joint research project was carried out under the fund of Value to Wood Program. The project is to further develop the range of possible applications for hollow core panels (HCPs), to construct and test prototypes for more demanding applications and to create optimization tools through the development of finite element models (FEM) for these geometrically complex assemblies for minimized materials content and optimized panel structure. The experimental works that mostly involved with development of alternative low density core materials that can be used for light weight sandwich panels were conducted in FPInnovations Quebec lab while the research team from University of Toronto worked for FEM modeling and the research team from University of British Columbia investigated a range of different applications of the light weight sandwich panels.
This report documents the research project done at FPInnovations with detail description of research methodology, results, conclusions and recommendation. It consists six sub-reports:
1. Development of Two-Stage Thermo-Reforming Technology for the Manufacturing of Cup-Shape Fibreboard. Part I. Investigation of Effects of Different Resin Systems and Secondary Hot Pressing on Panel Properties.
2. Development of Two-Stage Thermo-Reforming Technology for the Manufacturing of Cup-Shape Fibreboard. Part II. Manufacture of the Cup-Shape Fibreboard Panels.
3. Low Density Particleboard Made with Speciality Isocyanate and Polyurethane Based Resins.
4. Manufacture of Low Density Particleboard Using Lab Made Polyurethane Based Resin.
5. Effect of Wood Particle Geometry on the Density and Strength of Low Density Particleboard.
6. Development of Low Density Particleboard Using Hemp Shives and MDI Resin.
Des manufacturiers de lames de plancher et de panneaux collés sur chant pour composants de meubles font parfois face à un problème de microfissures en surface du bois. Ces microfissures sont généralement détectées suite à l’application de la finition en usine et parfois même suite à la livraison des meubles ou à l’installation des lames de plancher chez le client. Le problème des microfissures peut donc s’avérer très coûteux pour les manufacturiers de produits d’apparence. Dans le cadre du présent projet, le partenaire de recherche, un important manufacturier de meubles de salle à dîner, témoigne de l’augmentation significative des microfissures observées en surface des composants en période hivernale. Des hypothèses de formation de microfissures en rapport aux conditions hivernales sont avancées. Ainsi, les objectifs du projet consistent en 1) l’évaluation de l’impact des changements climatiques en cours de transport et d’entreposage de panneaux de type lamellé-collé sur la formation des microfissures en surface et 2) l’étude de l’influence du gel en période hivernale sur la formation de microfissures en surface du bois suivant la sortie des chargements des séchoirs.
Des essais de conditionnement de composants de tables caractérisés par des cycles de gel et de dégel du matériel ont eu lieu en laboratoire. Les résultats n’ont démontré aucun impact du gel sur la formation de microfissures en surface. Ainsi, les conditions de transport et d’entreposage en conditions hivernales caractérisées par le gel du matériel ne favorisent pas la formation de microfissures en surface des composants de meubles.
Un essai de séchage impliquant deux scénarios de refroidissement du bois caractérisés par une sortie rapide du chargement au gel et un refroidissement graduel en séchoir a été réalisé. Les résultats ont révélé que le refroidissement du bois à l’extérieur du séchoir en fin de procédé par temps hivernal n’a pas d’impact sur la formation de microfissures en surface du matériau. Ainsi, sur la base de ce résultat, la sortie rapide d’un chargement de bois (à 50oC) à l’extérieur du séchoir en période de gel ne favorise pas la formation de microfissures.
L’évaluation du matériel en usine dans le cadre des essais réalisés a démontré la présence de microfissures localisées en grande proportion dans des portions colorées du bois. Ces zones de couleur s’expliquent par la présence du bois de cœur mais aussi par des taches d’origines chimique et fongique. Certains types de taches associés par exemple à une dégradation fongique ou carie sont caractérisés par une altération des composants cellulaires du bois et une réduction de la résistance mécanique. Ces portions colorées s’avèrent donc propices à la formation de microfissures. La qualité de la ressource aurait donc un impact sur la formation des microfissures observées en surface des composants de bois.
This study presents a cradle-to-grave environmental profile for pre-finished hardwood flooring manufactured in eastern Canada and compares this to profiles for alternative flooring products such as carpets, ceramic tiles, vinyl, cork, and linoleum flooring. This is a life cycle assessment (LCA) study.
Conduct a cradle-to-grave LCA for eastern Canadian hardwood flooring in a typical residential application;
Create cradle-to-grave profiles for alternative flooring products for which existing LCA was available (carpets, ceramic tiles, vinyl, cork , and linoleum flooring) and their use in typical residential applications;
Compare and contrast life cycle environmental impact of eastern Canadian hardwood flooring with alternative flooring types (carpets, ceramic tiles, vinyl, cork flooring, and linoleum) used in residential applications.
This report discusses eco-labeling and the rise in interest of environmental product declarations (EPDs). EPDs are ISO Type III labels conveying non-judgemental life cycle assessment (LCA)-based environmental performance data about products. These documents work in principle like nutrition labels on food packages, transparently disclosing standardized data about the contents and enabling side-by-side comparison between products. EPDs are a user-friendly vehicle for bringing LCA data to the marketplace. In Europe and Asia, EPD development is on the rise, and some jurisdictions are moving towards making EPDs mandatory; this may have trade implications for Canadian exporters. Meanwhile, North America has been slow to follow this trend, although there is movement in the US towards development of standards. It is in the best interests of the wood products industry to accelerate North American activity in EPDs and position itself as a leader in industrial sustainability by developing EPDs early. Over two decades of work in LCA by the wood industry has already indicated that environmental metrics for wood products are generally better than those for competing products. In this report, EPDs are explained in terms of applications, benefits, risks and market drivers. We discuss how EPDs are created and identify global activity in EPD development and creation of national infrastructures. We address trade implications, assess Canada’s readiness, and provide recommendations for moving more quickly to bring the potential benefit of EPDs to the Canadian wood products sector.
The overall objective of this research is to develop a methodology that will foster the design of fire-safe buildings of wood or hybrid construction. This project aims to develop a design methodology (i.e., calculation methods) which will allow the calculation of the fire-resistance of CLT assemblies/construction. The methodology will take into account the thickness and number of laminations and their orientation, the species and strength properties of the laminations, the load imposed on the panel, and any additional fire protection such as gypsum board or plywood. This will provide manufacturers and designers a methodology to predict the fire-resistance of panels for use in various applications.
In order to establish calculation methods a series of experimental tests has been undertaken. To date, two CLT fire-resistance tests have been conducted at the NRC fire laboratory where the panels were subject to standard CAN/ULC-S101 fire exposure. Both 3-ply CLT assemblies consisted of 38 x 89 mm black spruce boards, where the two outer longitudinal plies consisted of SPF 1650Fb-1.5E machine stress-rated (MSR) lumber, and the inner transverse ply was SPF No.3/stud. Each panel was protected with two layers of 12.7 mm CGC Sheetrock® FireCode® Core Type X gypsum board. Thermocouples were placed behind each layer of gypsum board and embedded at 19-mm increments into the panels to a depth of 76 mm.
The first test was a floor assembly, where a load of 2.7 kPa was applied. The test was ended after 77 minutes due to equipment concerns from the laboratory staff, therefore structural failure was not reached. The greatest measured char depth in the panel was 11.2 mm. The maximum deflection of the floor was 32.1 mm.
The second test was a wall assembly, which failed due to buckling after 106 minutes when subjected to 333 kN/m. From one data point a charring rate of 0.4 mm/min was calculated. The maximum deflection of the wall was 55.3 mm. From the thermocouple data, it was determined that the two layers of gypsum delayed the onset of charring in both the floor and wall tests by approximately 60 minutes.
So far the proposed calculation methods have proved to be conservative in predicting the time to structural failure and charring rates.
Due to the difficulty of sourcing CLT assemblies to test, six additional full-scale fire resistance tests are to be completed in 2011-2012. The current test plan includes testing two more wall assemblies and four more floor assemblies. Tentatively, the next set of floor tests to be completed will be on a 5 ply unprotected assembly with the only difference between them being the type of adhesive used. Similarly, a 5-ply unprotected wall assembly will be tested. A composite floor assembly consisting of CLT with a concrete toping is also planned to be tested. This leaves one wall and one floor test to be finalized allowing for investigation of any questions raised in the tests identified above.
Starting with a brief introduction on energy efficiency trends and initiatives/programs in the residential construction sector, this report focuses on the causes of, and ways to reduce vapour condensation. It also covers performance of wood-frame building enclosures, specifically walls, traditional vented roofs and relatively new unvented roofs, during laboratory/field testing and service. It confirms that the key to achieving long-term durability for highly insulated walls and unvented roofs in cold and coastal mild climates is to ensure good air tightness and reduce air exfiltration, control indoor humidity, reduce outward vapour diffusion, and keep wood elements warm. For traditional vented roofs in cold climates the key is to ensure good sealing at ceilings, reduce indoor humidity and maintain good attic ventilation. Studies on ventilation reduction and optimization to potentially reduce attic humidity, in coastal mild climates in particular, are also discussed.
Based on the identified knowledge gaps in how to ensure good durability performance of highly insulated wood-frame building enclosure assemblies, the report provides recommendations for future work:
Conduct field testing of highly insulated building enclosure assemblies to further quantify vapour condensation potential under realistic indoor and outdoor conditions in the representative climates in North America.
Inspect older houses/buildings built with high levels of insulation in the building enclosure to assemble service performance data, and summarize solutions to achieving good durability and energy efficiency.
Further improve hygrothermal simulation tools to improve the prediction of moisture and energy performance and thereby the design and construction of highly insulated building enclosure assemblies.
Provide guidelines on durable, buildable and economical building enclosure assemblies to improve the design and construction of energy efficient wood-frame houses/buildings.
The progress related to these items has been reported.
A recent study at the University of British Columbia and FPInnovations has established a link between wood and human health. In the study the presence of visual wood surfaces in a room lowered sympathetic nervous system (SNS) activation. The SNS is responsible for physiological stress responses in humans. This result opens the door to a myriad of stress-related health benefits that the presence of wood may afford in the built environment. The application of wood to promote health indoors is a new tool for practitioners of evidence-based design.
Wood & Human Health Series; Issue 1 dealing with wood aesthetics
This study presents a life cycle assessment of two prototype biocomposite formulations manufactured at NRC-IMI in Boucherville, Quebec under a collaborative project between National Research Council of Canada-Industrial Materials Institute (NRC-IMI) and the Composites Department of FPInnovations on the “Development of cellulosic fibres/thermoplastic biocomposites”:
Formulation 1 – uses wood fibre with two biopolymers: polylactic acid (PLA) and thermoplastic starch (TPS). PLA is imported from Nebraska, US and TPS is produced at NRC-IMI using a locally available biopolymer source.
Formulation 2 - uses wood fibre and PLA.
The goals set to assess the cradle-to-gate environmental performance of the two formulations are:
Develop life cycle inventory for Formulation 1
Develop life cycle inventory for Formulation 2
Perform contribution analysis to identify significant inputs within the two formulations
Compare and contrast environmental performances of the two formulations
Compare and contrast environmental performance of the two biocomposite formulations with alternative materials such as nylon and polypropylene.
Ce projet vise à mettre au point une méthodologie et des outils pour aider les usines à évaluer les différentes solutions de triage offertes pour le séchage de bois du groupe EPS et identifier les solutions optimales spécifiques. L’étape du projet faisant l’objet du présent rapport consiste plus particulièrement à évaluer différents systèmes de triage offerts sur le marché dans des conditions hivernales (température du bois sous le point de congélation).
Quatre systèmes de triage ont été évalués soit le Préclasseur 3DELTA de Fabrication Delta, le MC-Pro 1500 de NMI, l’optimisateur de séchage du sapin et de l’épinette d’AUTOLOG (SAPTEK) et le système de pesée dynamique SPD de VAB Solutions. Les 3 premiers systèmes ont été testés à l’usine d’AbitibiBowater de Maniwaki tandis que le système par pesée dynamique SPD a été testé à l’usine de Canfor à Daaquam, mais en utilisant le même échantillon de sciages à l’état vert.
La proportion d’essences des pièces de l’échantillon était de 41 % d’épinette, 21 % de pin et 38 % de sapin. Les pièces ont été mesurées avec les systèmes dans des conditions de température du bois variant de -2 à 2°C. L’objectif consistant à évaluer les systèmes alors que la température du bois était sous le point de congélation n’a pas été atteint. Les pièces retenues pour fin d’analyse ont été séchées pour permettre d’obtenir la courbe de séchage pour chaque pièce. De cette façon, il a été possible de déterminer le temps de séchage pour chaque pièce à toute teneur en humidité intermédiaire ou l’inverse.
Tous les systèmes étudiés ont montré des gains significatifs en productivité pour un triage en deux lots de l’échantillon d’essences mélangées. Le potentiel maximal théorique de gain en productivité par le triage en deux lots est de 33,4 %. Le système 3DELTA a montré des gains en productivité de 28,9 %, le système SAPTEK de 28,4 %, le système MC-Pro 1500 de 24,9 % et le système de pesée dynamique SPD de 18,3 %.
À l’intérieur du groupe d’essence épinette/pin, le potentiel maximal de gain en productivité de l’échantillon trié en deux lots est de 8,6 %. Le système de pesée dynamique a montré un résultat de gain en productivité au séchage de 4,1 %, le système MC-Pro 1500 de 3,3 %, le système 3DELTA de 2,9 % et le système SAPTEK de 2,1 %. À l’intérieur du sapin, le potentiel maximal de gains en productivité de tri en deux lots est de 14,7 %. Le système de pesée dynamique SPD a obtenu un résultat de gain en productivité de 6,3 %, les systèmes 3DELTA et MC Pro-1500 de 3,5 % et le système SAPTEK de 3,3 %.
The scope of the program is to develop and publish Type III environmental product declarations (“EPDs”) for wood products (building products, furniture, pallets, etc.) manufactured in North America. Examples of products may include siding, decking, flooring, shingles, lumber and other board-type products, plywood and other panel-type products, furniture, and kitchen cabinets.
This product category rules (PCR) document is intended for companies preparing an environmental product declaration (EPD) for North American structural and architectural wood products (see section 6.2 for definition of product category). The users of this PCR will be manufacturers of North American structural and architectural wood products and other interested parties. This PCR has been developed under the general program instructions for the FPInnovations EPD Program on wood building products, prepared by FPInnovations, December 1, 2010. The PCR presents a structure that is intended to ensure a harmonious approach is taken to derive, verify and present EPDs for solid wood building products in North America.
This EPD addresses products from multiple manufacturers and represents an average for the membership of the Western Red Cedar Lumber Association (WRCLA), a non-profit trade association representing manufacturers of western red cedar products. This average is based on a sample that included two lumber mills in British Columbia (BC), combined with recent secondary data on western red cedar resource extraction from the Athena Institute. The total data represents 20% of western red cedar decking production in the year 2007.