The Canadian government published a new
regulation on the formaldehyde emissions from
composite wood products which prohibits the
import, sale or offer for sale of composite wood
products that emit formaldehyde beyond
established limits. The new law will come into force
on January 7, 2023.
Pathogen detection and identification have been vastly improved with advances in genomics; however, knowledge gaps remain around efficacy and use in wood commodities, especially in regulatory settings. In part one of this project, we compared detection efficacy of different methods on common export and import forest products. In-situ detection was more sensitive than traditional isolation, with 100% detection rates for some methods. However, there were several false positives in control samples. False positive detection of quarantine pathogens on wood products could be a serious problem in trade. The goal of part two of this project was to determine the cause of the false positives. In addition, we continued to compare detection methods by looking at point of care detection with a portable qPCR system and using RNA assays to test pathogen viability. False positives were likely due to DNA contamination persisting through the various wood processing steps. These results confirm the need for additional confirmation of pathogen presence or viability after a positive DNA test. RNA assays failed to detect pathogen presence in most samples. Further testing is needed to determine optimal RNA extraction conditions to provide meaningful results. Point of care detection using portable tools was comparable to laboratory methods and would provide a useful tool for pre-screening commodities for the presence of quarantine pathogens.
A number of test series have been conducted at FPInnovations to evaluate the lateral resistance, fire resistance, and acoustic performance of the new Midply shear wall configuration. The results showed that the seismic force modification factors prescribed in the NBCC can be used, along with the enhanced lateral strength and stiffness. Moreover, with some minor design
considerations, it was found that the new Midply with the resilient channels and insulation materials in both sides of the wall and both cavities can provide at least 1 hour of fire-resistance rating and provide at least an ASTC of 47.
Un certain nombre de séries d'essais ont été réalisées à FPInnovations pour évaluer la résistance latérale, la résistance au feu et la performance acoustique de la nouvelle configuration de mur de contreventement Midply. Les résultats ont montré que les facteurs de modification de la force sismique prescrits dans le CNBC peuvent être utilisés, avec une résistance et une rigidité latérales améliorées. De plus, avec quelques considérations de
conception mineures, il a été constaté que le nouveau mur de refend Midply avec les profilés souples et les matériaux d’isolation des deux côtés du mur et dans les deux cavités peut fournir au moins une heure de degré de résistance au feu et un ITSA d’au moins 47.
To improve the accessibility of genomics for the identification of wood inhabiting microorganisms to FPInnovations’ members, we compared three different methods for metabarcoding on environmental DNA (eDNA): cloning with first generation Sanger sequencing, amplicon metabarcoding with second generation Illumina sequencing, and lastly amplicon metabarcoding with third generation, long read sequencing with the portable MinION. We looked at costs for each method, speed, and difficulty. Illumina metabarcoding was the most economically feasible method. Cloning was difficult, being prone to failure and requiring extensive trouble shooting to complete. Illumina metabarcoding must be outsourced which can take more time for project completion; however, little in-house troubleshooting is necessary. Third generation sequencing is an attractive alternative for routine analysis. It is rapid, low-cost, and takes little up-front capital for start-up. However, it may not be feasible if used infrequently given the time required to learn the technology and the rapid expiration of unused flow cells. For occasional projects, it is recommended to outsource amplicon metabarcoding to a facility that sequences either with second or third generation sequencers, including data analysis.
The overall objective of this study is to provide information to building design practitioners that will help to improve accuracy of hygrothermal models and enable them to better use these models to predict the durability and thermal performance of wood-based building envelopes. To achieve this, hygrothermal models using WUFI Pro software are validated with experimental data obtained from five wood-frame wall assemblies, with different insulation and vapour control strategies, exposed to the climatic conditions of Vancouver from October 2018 to May 2020. This exercise provides a set of model input parameters that the practitioner can use to assess similar structures exposed to similar environmental conditions. Sensitivity analysis is conducted on the model input parameters to establish which are the most important in obtaining a good fit to experimental measurements, and therefore accurate prediction of assembly performance. There is also discussion on limitations of the hygrothermal model.
The definitive guide for the mass timber design and construction of tall buildings has been updated to align with changes to national codes and standards. It builds on 12-storey mass timber gravity systems as an Acceptable Solution in the 2020 edition of the National Building Code, and targets supporting Alternative Solutions that will enable wood to be used beyond 12 storeys.
To download the book, go to: https://web.fpinnovations.ca/tallwood/
This InfoNote summarizes the verification and validation that the current design requirements of Annex B of CSA O86 can also be applied to small framing members used in unprotected and protected lightweight wood-frame assemblies, e.g., walls and floors. With minor editorial changes, the scope of application of Annex B of CSA O86 could include all wood and wood-based products listed in CSA O86, regardless of their original and residual dimensions.
Originally developed in Europe, self-tapping screws (STS) have become the proprietary fastener of choice in recently built mass timber buildings in North America. STS offers some advantages over other types of fasteners, such as (a) installation of STS inside wood members is easier as it does not require pre-drilling of holes inside members, (b) the yield moment, torsional strength and tensile strength of STS is comparatively high as the material forming the screw is usually hardened after rolling the thread, (c) the stiffness of the resulting connection is higher and the chances of slipping are less (Frese and Blass, 2009), and (d) STS with long threaded lengths makes it feasible for use in large structural members, e.g., mass timber products.
Recently, issues have been raised on failures of STS due to shrinkage and swelling of wood products resulting from moisture content changes, particularly during construction in the coastal climates. Failures of STS have been reported by structural engineers and contractors of several mass timber projects in NA. This has greatly increased the liability of practitioners involved in mass timber construction.
This project will investigate the material properties of several types of mass timber products and self-tapping screws. These material properties will be used in an analytical and numerical prediction model to describe the behaviour of self-tapping screws in mass timber products under moisture content variation.
This article in the Journal of Commerce highlights FPInnovations Sustainable Construction spotlight series. Experts at FPInnovations believe using wood technology could play a major role in helping Canada meet its climate goals. This article may be accessed on the Journal of Commerce's website: https://canada.constructconnect.com/joc/news/resource/2022/06/fp-innovations-pushes-wood-as-solution-to-climate-goals-affordable-housing
The full FPInnovations In the Spotlight series can be accessed at: https://web.fpinnovations.ca/in-the-spotlight-sustainable-construction/
Due to the awareness of the importance of reducing environmental footprint and the rising costs of construction, timber structures have been increasingly attracting attention and, subsequently, adoption for being built taller and larger. Computer modelling plays a crucial role in the analysis and design of large and tall timber structures, and in the development of wood-based products, connections, and systems. A survey by FPInnovations showed that practising engineers are typically unfamiliar with timber structure modelling, and researchers generally lack resources for advanced modelling of timber systems. Therefore, in 2020, FPInnovations initiated a project to develop a guide that would support the application of numerical modelling on the analysis and design of timber structures, and the development and optimisation of wood-based products and systems. The Modelling Guide for Timber Structures is the result of a global effort involving over 100 coilaborators, including experts from research institutes, consulting firms, manufacturers, software companies, governmententities, and associations.
This guide brings together the experience gained from recently built timber projects, and the latest research development in the modelling of timber structures. It includes a wide range of practical and and advanced modelling topics, such as key modelling principles, methods, and techniques specific to timber structures; modelling approaches and considerations for wood-based components, connections, and assemblies; and analytical pproaches and considerations for timber structures during progressive collapse, wind, and earthquake events. It also presents the differences in the modelling approaches to timber, steel, and concrete structures.
The information presented in this guide is intended to assist practising engineers to apply computer modelling to timber structures, enrich researchers' resourcesfor advanced computer modelling of timber systems, and assist software companies in identifying knowledge gaps so that they may upgrade programs accordingly to accommodate he advanced computer modellingof timber structures.
Le gouvernement du Canada a publié un nouveau
règlement sur les émissions de formaldéhyde des
produits de bois composite qui interdit
l'importation, la vente ou la mise en vente de
produits de bois composite qui émettent du
formaldéhyde au-delà des limites établies. La
nouvelle loi entrera en vigueur le 7 janvier 2023.
FPInnovations’ three-generation floor vibration-controlled design methods in NBCC and CSA O86 ensure market acceptance by consumers. Since 1990, there have been very few consumer complaints. This reinforces the use of wood as a quality building material and contributes to expanding market shares of wood construction in Canada.
Comme l'ont démontré le développement et la mise en oeuvre des codes des méthodes de conception de troisième génération pour lutter contre les vibrations des planchers, FPInnovations joue un rôle important au Canada et à l'échelle internationale dans les comités de codes et de normes visant à protéger les consommateurs et l'industrie du bois et contribue à la croissance continue du marché de la construction en bois à l'échelle mondiale.
WoodST is capable of calculating heat transfer, charring rate, load-displacement curve as well as the time and mode of failure of timber structures exposed to fire, thus providing a cost-competitive solution for the fire safety analysis of timber structures. This InfoNote briefly introduces the development and verification of WoodST. Two applications of WoodST are also demonstrated.
WoodST est capable de calculer le transfert de chaleur, la vitesse de carbonisation, la courbe charge-déplacement ainsi que le moment et le mode de défaillance des structures en bois exposées au feu, offrant ainsi une solution à coût compétitif pour l'analyse de la sécurité incendie des ossatures en bois. La présente note d’information présente brièvement le développement et la vérification de WoodST. Deux applications de WoodST sont également présentées.
Building high energy efficiency has become a must to reduce carbon emission from the built environment and to meet needs of consumers. Industrialized construction provides an effective way to produce highly insulated and airtight building envelopes to achieve superior building performance, such as Net Zero Energy. However, it is important that as other attributes (e.g., seismic, wind, fire, vibration, etc.) are being addressed, further research is needed to develop well rounded building envelope solutions. Meanwhile, improvement may be made in automated production equipment and software to optimize and monetize these solutions.
Il est devenu indispensable de construire des bâtiments à haute efficacité énergétique pour réduire les émissions de carbone dans l’environnement et répondre aux besoins des consommateurs. La construction industrialisée est un bon moyen de produire des enveloppes de bâtiment bien isolées et étanches à l’air et, par le fait même, d’accroître la performance énergétique des bâtiments (p. ex consommation énergétique nette zéro). Cependant, il est important de tenir compte d’autres attributs (p. ex. charges sismiques, vent, feu, vibrations, etc.). Il faudra poursuivre les recherches pour trouver des solutions durables en matière d’enveloppes de bâtiment. Entre-temps, il est possible d’améliorer l’équipement de production automatisée et le logiciel qui l’accompagne afin d’optimiser et de rentabiliser ces solutions.
This new study aims to generate hygrothermal, particularly moisture-related performance data for light wood-frame walls meeting the R22 effective (RSI 3.85) requirement for buildings up to six storeys in the City of Vancouver. The overarching goal is to identify and develop durable exterior wood-frame walls to assist in the design and construction of energy efficient buildings across the country. Twelve test wall panels in six types of wall assemblies are assessed in this study. The wall panels, each measuring 4 ft. (1200 mm) wide and 8 ft. (2400 mm) tall, form portions of the exterior walls of a test hut located in the rear yard of FPInnovations’ Vancouver laboratory. This report, second in a series on this study, documents the performance of these wall assemblies based on the data collected over 19 months’ period from October 2018 to May 2020, covering two winter seasons and one summer.
