All images courtesy Calstar Products Feature Carbon, Environmental Product Declarations, and Brickwork Reducing footprints through masonry By Maranda Bennett A primary component of Canada’s built environment, brick masonry is one of the oldest construction materials, and has been in use for millennia. Its durability has helped it stand the test of time, and its esthetics continue to make it a desirable, in-demand option in many locales. Clay brick is inherently sustainable in some ways. It has a long lifespan and a high thermal mass, and it is often locally extracted and manufactured. However, clay brick is less sustainable when it comes to the amount of energy consumed and greenhouse gases (GHGs) emitted during production. In recent years, the brick industry has sought new ways to reduce these environmental burdens. A few brick plants have switched to alternative 94 October 2013 CC_Oct13.indd 94 fuel sources for their manufacturing, and some companies incorporate recycled materials into the bricks. While these efforts are certainly laudable, they do not address some of the most urgent environmental threats: the intensive consumption of fossil fuels and the associated emission of GHGs (e.g. carbon dioxide [CO 2 ]), which are primary causes of climate change. Clay brick hardens through firing, typically in tunnel kilns operating continuously at about 1100 C (2000 F) for up to four days. During normal operations, these kilns are rarely shut down, except for maintenance. Kilns are typically fired with natural gas, coal, or petroleum coke—all of which emit significant CO 2 in their combustion. Co nstruction Canada 10/8/13 11:46 AM