Libraries are traditionally stark repositories of knowledge. Installing a green roof was an opportunity to generate community interest in green design to make this facility a dynamic teaching tools for sustainable design and environmental awareness.
The green roof was incorporated as part of an overall strategy to reduce and conserve energy costs where possible. Solar (photovoltaic) panels provided by the Seattle City Light Green Power Panel installed on the northern edge of the roof will monitor the amount of electricity captured and collected onsite. Energy generated from these panels is fed back into the city's power grid, reducing the library's energy bills. Additionally various rooftop sensors measure wind speed, direction, sunlight etc.
The gently curving roof is visible from the periscope and observation deck and invites visitors to engage in the green roof's ecology above the street. The project illustrates green buildings are feasible within a modest budget, presenting the community with an ideal example of benefits realized when sustainable design combines with extraordinary architecture.
As the site is in an urban setting, the challenge was to develop the site in a restorative manner. Formerly home to a bank and a parking lot, hardscape compromised 100% of the lot coverage. Today, combined with the green roof and planters at the building perimeter, the hardscape has been reduced to 20% of the lot coverage.
The seamless waterproofing membrane used for the green roof project, Monolithic Membrane 6125EV-FR® (fabric reinforced, environmental grade, 25% recycled content), is a hot fluid-applied, rubberized asphalt that forms a long-lasting tenacious bond to the substrate. MM6125EV-FR's® unique formulation, which includes inert clay fillers, provides excellent resistance to acids and fertilizers.