Written by Leila Tolderlund; Assistant Professor, University of Colorado Denver
Leila Tolderlund is an assistant professor (CTT) and associate chair in the Landscape Architecture Department at University of Colorado Denver.
The recent implementation of the Green Building Ordinance in Denver, Colorado has created a new demand in education of Best Management Practices (BMPs) for green roof designers and installers in our region. The climate in the western US is – and has been - a challenge for green roof builders and roofers in general. Roof materials, especially the waterproof membranes, are prone to shorter life spans here than in other climates. This is due to extreme freeze-thaw cycles, high winds, extensive exposure to UV light, and the frequency of hail storms we have in this region.
Studies have shown that living green roof layers on top of roof membranes can help protect and prolong the life of roof membranes up to 3-5 times, by protecting them from UV rays, wind, hail, and by reducing expansion and contraction of roofing materials by moderating temperature fluctuations. Waterproofing membranes under green roof layers need to be replaced less frequently as a result. This alone can generate significant return on capital investment for the building owner (and significantly reduce the amount of roofing material ending up in a landfill) over the lifespan of the building. When combined with energy savings, improved real estate values, and reduced stormwater fees, the business case for green roofs in Colorado is a strong one.
A better understanding of responsible design, implementation, and maintenance of green roofs in this climate will result in a rise in green roof projects and an improvement in their performance in Colorado. The increase in green roof projects will be accompanied by a multitude of added economic, social, and environmental benefits, such as improved stormwater management; the cooling and cleaning of the air; improved urban landscapes, biodiversity and livability; and an increase in real estate values, to name a few.
Learn more about Green Roof and Wall best management practices in Colorado at the Colorado Living Architecture Seminar on August 9 at University of Colorado Denver - register today!