The new executive, Carol Lewis, greeted the group. John R Shelly, University of California, was chair of the meeting. The meeting’s ‘Focus Day’ session emphasised smart building for the 21st century. California’s housing and community development director Lynn Jacobs, said: "California continues to experience very high rates of population growth and further tightening of its housing markets". She said housing production had not kept pace with the state’s needs, particularly in the coastal and metropolitan areas. The annual need is 220,000 units, but this has not been met since the 1980s. Each year, 500,000 new residents move into the state. She said California’s home ownership rate is the second lowest in the US, yet the housing industry is the second largest industry group in California’s economy, with one million workers employed. It makes up 11% of the economy.
Ruben D Grijalva, director, California Department of Forestry and Fire Protection, said 95% of the forest wildfires are contained at l0 acres or less. He advocated 100ft of space between combustibles. A major problem is flying embers. Kate Dargan, assistant state fire marshal, said building standards have aimed to eliminate conflagrations in urban areas. The same goals are driving the urban/forest interface. Dr Jim Bowyer, retired from the University of Minnesota, was somewhat critical of ‘sustainability’ classifications. "A sustainable material is theoretically infinitely abundant and capable of being produced, used, and disposed of or re-used without permanently impacting the earth’s natural systems. Despite the reality that producing all materials results in significant environmental impacts, only wood is held to standards linked to extraction. The result is designation of environmentally preferable materials using single attributes that often don’t stand the test of rigorous assessment," he complained. Dr Bowyer also criticised systems for not considering embodied energy in a product such as steel studs.
He said life-cycle assessment procedures only provide a standardised framework for determining environmental burdens linked to a product or process. He added that every such assessment has shown lower environmental burdens associated with wood buildings compared with those made from other materials. He said: "Wood will re-emerge as the responsible environmental material. "Architects and builders who look beyond the biases and politics of current green building initiatives, and to whom the sustainability issue really matters, will find wood the environmentally preferable material for almost every application". Ann Edminster, environmental design consultant, Pacifica, California, advocated substituting wood, whenever possible, for more problematic materials. However, she said, "We only allow it one life and we don’t make it last long enough." She advocated building smaller houses designed for enduring value. She also advocated wooden studs in commercial buildings.
Dr Thomas M Bonnicksen, Texas A&M University, called attention to the US’ alarming forest health and wildfire crisis. He said many public forests are dangerously overgrown and more than 32 million acres burned in the last five years. He observed that public attitudes toward forest management have created an atmosphere in which a hands-off, preservationist approach has prevailed recently. He said that that approach has left forests increasingly susceptible to catastrophic wildfire and Americans more dependent on wood products from places in which they have no say over environmental practices. Dr Bonnicksen declared that Californians are totally detached from the environment around them. He advised: "Let foresters be foresters. We must sell wood products to pay the cost. Just taking the little stuff is foolish. Use the historic forest as a model in forest restoration. Agencies must have the will, the incentive and the know-how to mark the trees. It’s our country’s heritage".
Dr Bonnicksen ended: "By embracing restoration forestry, we can enhance biodiversity, make communities safer and ensure a sustainable supply of wood products to meet the needs of a growing population". To help accomplish such a goal, Susan L LeVan Green, USDA Forest Products Laboratory, Madison, Wisconsin, is researching new uses for forest thinnings, including wood-plastic composites, engineered roundwood structures, erosion control products, water filters, biomass power and biofuels. Herbert Kennedy, Georgia-Pacific Resins, Inc, Monroeville, Alabama, said the economic outlook is generally favourable for North America and the energy market is not as bad as it may appear, but the trade deficit is at a peak. He recognised that composite panels are a growing part of the North American forest industry and wood adhesive vitality is important to the panel industry. Skyrocketing oil prices are big news, but he calculated that 1980 oil prices were higher, in the same dollars. He predicted US$40 per barrel in 2009.
He recognised that resins are affected by oil prices. Regarding urea, he said: "We are at the mercy of the agricultural market". He reported limited reinvestment in adhesives capacity because of recent highly competitive adhesive markets. Mr Kennedy said OSB uses more adhesive per square foot than plywood and warned that I-joist capacity is above demand. Discussing wood thermoplastic composites for resistance to decay and moisture, Dr Michael Walcott, Washington State University, reported that polymer contents of less than 35% can significantly retard intrusion of both moisture and fungi. Kate E Semple, University of British Columbia, said isocyanate wood binders are generally more sensitive to open mat assembly times in composite board production than other systems. She added that holding time for pMDI-blended wood furnish is believed to be no more than five hours.
She reported that panels made from shortleaf pine, blended and immediately pressed, were significantly higher in strength, particularly in internal bond, than those in which the mat was held for 10 or more hours before pressing. Zhiyong Cai, Forest Service Forest Products Laboratory, Madison, Wisconsin, said his study indicates that thin-layer glass fibre (3.5% OD weight) overlays in MDF and flakeboard production can improve MOE, MOR and resistance to thickness swell and water absorption. He added that the technique could increase serviceability and market potential of wood composites used as exterior siding products. Todd F Shupe, Louisiana State University, reported that the LSU AgCenter is developing a closed-loop preservative-treated wood recycling programme. Options are recycling the treated wood and removal of the toxic preservatives. A goal is to scale up to pilot plant stage research to develop wood composite panels from preservative-treated wood. The primary interest is in wood liquefaction, hydrothermal treatment and composite products.
Conrad Kevin Groves, Forintek, Vancouver, BC, Canada, indicated that a number of chemical products can be applied to OSB surfaces to significantly reduce mould growth held at high humidity for up to eight weeks. Nicolas Andre, University of Tennessee, Knoxville, is studying on-line near-infrared spectroscopy to predict the buffer capacity of particleboard furnish. A high buffer capacity will slow resin cure during pressing and lead to low internal bond. He said accurate monitoring will help control panel quality by adjusting process parameters such as the amount of resin and additives, press closing time and line speed. John O’Connor, Oregon State University, reported on mechanical compression perpendicular to the grain to increase wood density, increasing strength and stiffness of low density wood for use as components in structural composites.
Sumin Kim, Seoul National University, South Korea said that MDF and particleboard emitted greater amounts of VOCs than did laminate and engineered flooring. Dr Rupert Wimmer, University of Natural Resources & Applied Life Sciences, Austria, said use of natural fibre composite automotive interior parts is increasing. The most common process prior to compression moulding is non-woven needle-punch technology. This involves kenaf and polypropylene laid aerodynamically to a loose fibre fleece before entering a mechanical needle-punching consolidation with 7,200 needles. He said advantages of the product include low weight, low production-energy use, good acoustic, mechanical and safety properties, renewable resource balance and low allergic reactions during production. There are drawbacks: unpleasant odour, lower strength, mould growth, moisture absorption, low product uniformity, limited heat resistance and poor fire resistance.
