A field test of six millwork preservatives has been ongoing for twenty years, using a simulated window corner, or "Y-joint", as the test unit. Three preservatives provided excellent protection to white pine and white spruce: 5% pentachlorophenol in varsol, phenyl mercury oleate in varsol, and 0.75% oxine copper in varsol.
A transparent coating with long-term performance could help wood maintain its share of residential markets against material substitution and potentially expand markets in recreational property and non-residential buildings. While transparent coatings can be made reasonably resistant to UV some UV likely penetrates to the wood and by necessity clear coatings are transparent to visible light. Visible light can also cause damage over the long term thus the underlying wood needs additional protection. Four novel UV protection systems were tested as pre-treatments on uncoated wood and under three coatings, a water-based film forming coating, a water-based acrylic varnish and a solvent based water repellent. Samples were exposed to natural weathering facing South at 45° at a test site in Gulfport, Mississippi, in collaboration with the USDA Forest Products Laboratory. The test material was inspected every six months for discolouration, mold and stain, coating water repellency, flaking, erosion and cracking and substrate condition. After 24 months exposure, coatings over the combination of UV absorber and lignin stabilizer identified by Stephen Ayer were performing better than the same coatings applied over the combination recommended by Ciba and coatings over both pre-treatments were performing substantially better than controls with no pre-treatment. Projection of fitted curves beyond the data appears to indicate that pretreatment may double the life expectancy of the coating. There was no consistent effect of the synergists on either combination at this time.
A field test of six millwork preservatives has been ongoing for 25 years, using a "Y-joint" as the test unit. Three preservatives provided excellent protection to white pine and white spruce: 5% pentachlorophenol in varsol, phenyl mercury oleate in varsol, and 0.75% oxine copper in varsol.
The objective of this initiative is to re-evaluate Forintek's research strategy and the Canadian Wood Council's technology transfer strategy in durability of wood products and systems in the light of changing industrial, regulatory, environmental, and social factors. Forintek and the CWC chose to undertake this process jointly, in order to develop well-matched parallel activities that are mutually supportive and grounded in common underlying objectives. In this way, both organizations can most effectively and efficiently address our members' needs in an area of growing challenges for the wood industry.
The first step in the strategic planning process was the creation of a joint CWC/Forintek Durability Guidance Group. This group was canvassed for input on high priority issues related to wood durability. Forintek and CWC then developed ideas for deliverables or tasks in research and technology transfer, respectively. At this stage we are looking for input on the degree to which this draft strategy addresses industry needs.
Three Gram negative bacteria isolated from brownstained western hemlock were investigated for their capacity to produce hemlock brownstain. Brownstain was observed when infecting western hemlock with two bacteria. Oxygen was strongly indicated as being indespensable for the development of brownstain in infected samples. However, pH did not seem to influence the production of this stain.
Environmental product declarations (EPDs) are a standardized way for manufacturers to report quantified environmental impacts of their products. EPDs are developed in line with well-established guidelines from the International Organization for Standardization (ISO) to ensure rigorous and transparent procedures are followed.
Commercial and multi-family residential construction represents a growth area for the Canadian wood products industry. To capitalize on this opportunity, a thorough understanding of the necessary products and system attributes will be essential. Adequate levels of noise/sound control in multi-family buildings are mandatory requirements of building codes in Canada, the United States, Europe, and most developed Asian countries. In many jurisdictions, these requirements are as strictly enforced as those for structural sufficiency and fire safety. Much effort has been spent on evaluation of sound transmission class (STC) and impact sound insulation class (IIC) of floor and wall assemblies and on studies of flanking transmission in multi-family dwellings in Canada. However, continuing occupant complaints of poor acoustic performance in wood-frame buildings that appear to have been built according to wall and floor construction practices recommended in building codes suggest the existence of gaps in current noise control techniques.
Forintek initiated this project to investigate the relative importance of noise transmission in wood-frame residential buildings in comparison with other building serviceability issues, and to conduct a pilot study to examine construction designs of wood-frame buildings that exhibit unsatisfactory and satisfactory noise control and to identify existing gaps in current noise control techniques.
A literature review and survey of 123 occupants of wood-framed multi- and single-family residential buildings was conducted to determine the relative importance of noise transmission in comparison with other building serviceability attributes. Case studies were conducted on construction details and designs of six new wood-frame condominiums and one single family-house that were built according to code requirements and recommendations for controlling noise transmission.
We found that the general public had high expectations regarding adequate acoustic privacy. Even single- family house builders considered low sound transmission important. The multi-family building occupants ranked “sound insulation” the most “important” serviceability attribute, while single-family occupants were most concerned with “water penetration and condensation”. The lowest level of “satisfaction” was given by all respondents to “noise transmission” for their current residences, including single-family occupants, who had ranked it as not being so “important”. The case studies revealed that, current construction practices were much more effective in controlling airborne sound transmission than impact noise. The footfall noise transmission from stairs through the walls is still an unresolved issue that is not considered in the current Canadian Building Code. The low frequency footfall noise transmission between vertically-stacked units was the common complaint in some of these buildings. With no requirement for impact sound insulation in the current National Building Code of Canada, and with our existing knowledge gap concerning low frequency footfall noise transmission problems and solutions to control them, builders, acoustics consultants and design engineers have simply tended to blame wood building materials for noise-related complaints.
We concluded that if we are to satisfy the occupants of both single-and multi-family wood-frame buildings and to provide confidence for builders and design engineers in wood-frame construction with satisfactory acoustic performance, a much greater effort is needed to improve sound insulation including development of better sound insulated wood-frame systems and building materials as well as retrofitting techniques. Acoustic performance will be a critical factor for the wood products industry in gaining a greater share of the multi-family construction market and in competing with other building materials.
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.
