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.
A test program was conducted to generate hygrothermal performance data for light-wood-frame exterior walls meeting the R22 effective (RSI 3.85) requirement for buildings up to six storeys in the City of Vancouver. Six types of exterior wall assemblies, with 12 wall panels in total, were tested using a test hut located in the rear yard of FPInnovations’ Vancouver aboratory. This document provides a brief summary of the test and performance of these walls based on the data collected over the 19 months’ period from October 2018 to May 2020
Un programme d’essais a été réalisé en vue de générer des données sur le rendement hygrothermique des murs à ossature légère de bois qui répondent à l’exigence R22 (RSI 3,85) pour les bâtiments d'au plus six étages à Vancouver. Six types d’assemblage de mur extérieur, avec un total de 12 murs extérieurs, ont été mis à l’essai à l’aide d’une hutte d’essai située dans la cour arrière du laboratoire de FPInnovations à Vancouver. Le présent document présente un court résumé de l’essai et du rendement de ces murs en se basant sur les données recueillies sur une période de 19 mois, soit d’octobre 2018 à mai 2020 (Wang 2021).
This study focuses on measuring the wood moisture content (MC), temperature, and relative humidity (RH) (and the corresponding vapour pressure gradients) through each wall assembly to assess its hygrothermal performance. Controlled moisture loads, in the form of vapour
(achieved by maintaining a relatively high indoor RH) and liquid water (achieved by periodically injecting water to the wetting pads installed on the wood panels) are employed to stress these walls for investigating their moisture-related behaviour. After the wall panels and most instruments were installed but with the CLT directly exposed to the interior environment, a high indoor RH in range of 70-80% was maintained, starting mid-December 2020 inside the test hut to condition the wood to achieve comparable moisture gradients among the eight CLT panels. The test walls were closed in with interior framing (and interior insulation of walls No. 1 and No. 2) and drywall installed, followed with interior finishing in late January 2021. The indoor RH was afterwards set to be around 50%. Water injection is planned to start in the summer of 2021. Test results and performance of these walls will be presented and discussed in future reports.
Hügelkultur as a debris management technique in forest fuel reduction treatments. Developing a research plan to evaluate the flammability of constructed debris piles (hugels)
Disposal of woody debris and vegetative matter from forest fuel reduction treatments is a challenge and alternatives to conventional methods of pile burning and chipping are being considered. The construction of hugels is proposed as a debris management technique that would configure debris on site in a less flammable state. This research design presents considerations for development of an experimental burn site, test methods, and data collection methods that can be applied in evaluating and comparing the flammability of hugels constructed with different fuel components and construction methods.
Disposal of woody debris and vegetative matter from forest fuel reduction treatments is a challenge and alternatives to conventional methods of pile burning and chipping are being considered. The construction of hugels is proposed as a debris management technique that would configure debris on site in a less flammable state. Flammability of piled debris (hugels) and the productivity of hugel construction are key considerations in assessing the viability of this debris disposal method.
Another consideration in assessing hügelkultur as a long-term debris management strategy is the decomposition of hugels and the evolving flammability of hugels. Research literature does not speak directly to the changing flammability of piled debris (and more specifically hugels), but this literature search attempts to locate material relevant to decomposition of woody debris in a hugelkultur environment.
Hügelkultur as a debris management technique in forest fuel reduction treatments. A comparative productivity evaluation of a fuel reduction treatment incorporating hugels
Disposal of woody debris and vegetative matter from forest fuel reduction treatments is a challenge and alternatives to conventional methods of pile burning and chipping are being considered. The construction of hugels is proposed as a debris management technique that would configure debris on site in a less flammable state. While flammability of piled debris (hugels) is a key consideration in the viability of this debris disposal method, the cost of the operation must also be considered.
This research design presents the development of test methods and data collection methods that can be applied in evaluating the productivity of a fuel reduction treatment that incorporates construction of hugels as a debris management tool. Comparative productivity trials will evaluate these productivity results in relation to fuel treatments that apply conventional debris disposal methods.
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.
The current regeneration challenges posed by salvage logging following large-scale disturbances in western Canada, such as wildfire and mountain pine beetle, warrant the need for cost-effective reforestation strategies. Mechanized ground-based direct seeding was assessed in a variety of conditions to explore viability, determine which factors influence success, and determine the expected establishment rate when seeding with B.C. tree species. This report includes guidelines and recommendations for implementing direct seeding in B.C., based on observations from operational trials established in 2013-2017 across the province.
The biomass yield per hectare predicted for the Dawson Creek TSA is 32.3 oven-dried tonnes per hectare (odt/ha) from harvest residues. The biomass ratio, which is the ratio of recovered biomass to recovered merchantable roundwood, is estimated at 19.2%. Over the next 10 years at total of 1.59 million odt of available biomass are predicted to be generated by harvest in the Dawson Creek TSA, or approximately 160,000 odt/yr. Of this, approximately 1,242,000 odt in total, or 124,000 odt/yr, is expected to be available at the economic price of $60 per oven-dried tonne. Approximately 98% of the total predicted volume is expected to be available at $90/odt: a total of 1.56 million odt, or 156,000 odt/yr.
