Life cycle analysis is one of the most commonly accepted methods for analyzing the environmental impacts of a product. LCA is a comprehensive measure of the total environmental impact of a product, assembly or structure. True to its name, LCA is a holistic measure that examines the entire lifecycle of a product from start to finish. Life cycle assessment measures the energy expended during all aspects of the life span, encompassing the extraction, manufacture, distribution, use, maintenance and disposal of raw materials.
The environmental impacts of wood compared to other materials
LCA measurements show that solid wood and engineered wood consistently outperform steel and concrete in environmental sustainability. The many comparative advantages of wood include less energy consumption during production, less greenhouse gas emissions, less air and water pollution, and less production of solid waste.
A 2015 Australian study compared the lifecycle environmental impacts of two apartment buildings, one built with a light timber frame and the other with concrete. The study measured factors ranging from greenhouse gas emissions to the release of chemicals, which contribute to acid rain. The timber structure scored higher in three of the five categories, with most impacts occurring within an assumed 60-year lifespan. The study concluded that timber construction provides a greener building option over the life of a building. The study also found that much of the environmental benefit of the wood option was due to its lightweight design, a design advantage that offers many benefits including cost savings. (Forest & Wood Products Australia, “A Comparative Life Cycle Assessment of Two Multi Storey Residential Apartment Buildings”, July 2015.)
Two popular tools for estimating LCA are the Athena Environmental Impact Estimator and the Building for Environmental and Economic Sustainability (BEES) software, which also includes an economic performance score.
Environmental Product Declarations (EPD) and EPD Transparency Notes
Even with advanced LCA tools, sustainability is sometimes difficult to quantify. Environmental Product Declarations (EPDs) provide construction teams with scientific information on environmental impacts to facilitate more informed building material choices.
In accordance with ISO 14025, Environmental Labels and Declarations, an EPD gives a third-party verified assessment of a product’s environmental performance, including global warming potential, primary energy consumption, consumption of material resources , non-hazardous waste generation, acidification potential, smog potential and other measures.
Since EPDs are often lengthy, EPD Transparency Briefs have been developed to provide a shorter and more readable summary of an EPD’s most critical data: third-party verified product data based on life cycle. which are used in certification and rating systems for green buildings. .
The American Wood Council (AWC) publishes EPDs and EPDs Transparency Briefs for LVL, I-joists, softwood plywood, OSB, glulam, softwood lumber and other products wood.
APA Green Audit Reports
The APA Green Verification Reports help building officials and design professionals determine a product’s eligibility for points against recognized green building standards.
Green Verification Reports consist of a checklist designed to help document the compliance of individual engineered wood products manufactured under an APA-audited quality program to globally recognized green building standards. international, national or industrial, including ICC 700-2015, ICC 700-2012, ICC 700-2008, LEED v4, 2009 LEED and 2009 LEED Canada.
Learn more about the environmental benefits of engineered wood products at> https://www.apawood.org/green-building.