Award

A PR IL 2019 | 17 Green Roofs & Walls PHOTOGRAPHY COURTESY NEDLAW LIVING WALLS PHOTOGRAPHY COURTESY HYDROTECH MEMBRANE CORP. Like Klassen, Ron Schwenger, president at Architek Sustainable Building Products Inc., is excited about the forthcoming City of Vancouver's policy on green roofs, but adds that, "in order for it to be a success, Vancouver must learn from other cities like Toronto and San Francisco that have already enacted a similar policy. "Cities that didn't have clear construction standards, ended up with a great deal of low-cost, non-performing roofs being installed. The city will save money in stormwater mitigation and cleaner air if the green roof is installed correctly, and will mitigate the heat island effect. None of this can happen if the green roof is fail- ing," says Schwenger, who attended the Green Roofs for Healthy Cities symposium with RCABC's Klassen last year. "The message was loud and clear at that meeting – please include construction standards in your bylaw. The city needs to know that ROI can only happen when the correct standards are put in place." According to Schwenger, "in order to ensure the industry continues to move forward, another area of consideration is to take an engineered, rather than the traditional planter style approach to roof top gardens." "The current mindset is to employ a planter approach which usually involves either starter curbs or a full planter retaining wall, which are physically tied into the suspended slab. This creates two problems: more complex waterproofing that causes disruptions in the otherwise smooth and clean surface of the suspended slab, and bath tubbing. For example, the independent planters create an independent waterproofed space that requires its own independent drainage, leading to unneces- sary extra costs. Every additional drain can be upwards into thousands of dollars." Additionally, he says that in comparison, "an engineered approach to intensive rooftop landscaping allows for all of the landscaping – both hardscaping and softscaping – to be above the robust drain board assembly so that the entire landscape system is floating. This also includes the retaining walls for planters. This results in an uninterrupted drain plain underneath and allows for a much higher performance building envelope. Engineered intensive green roof systems allow for future changes to the rooftop landscape design, without involving the building envelope." While interest was in biophilia and biodiversity in the past, Hydrotech Membrane Corporation is now seeing increasing interest in other areas. "Currently, there are a lot of projects where the main emphasis in the green roof centres on stormwater management, especially with how green roofs, and blue roofs, address retention and detention. Wind uplift continues to be a factor given the 2015 release of CSA A123.24, which sets the testing protocol for modular vegetated roof assemblies," says Marjolaine Auger. Auger adds that as a result the company is seeing a staggering amount of requests for its Garden Roof Blue Roof assembly, which can address both stormwater retention and detention within the same footprint on the roof. Hydrotech has been involved in a number of prolific projects, which includes the development of the Northwestern Biomedical Research Center in Chicago. "This tower and base of the building generated a very large stormwater deten- tion volume requirement. Since the project was required to have a green roof, placing a six-inch Blue Roof underneath the green roof became the solution that Hydrotech developed. This became the genesis of Hydrotech Garden Roof Blue Roof," explains Auger. Looking ahead, Hydrotech sees green roofs as not only the "fifth façade" of a building, keeping the interior protected, but also being recognized for the value that horizontal space represents. "Rooftops are becoming active pedestrian spaces, adding desperately needed green space to urban areas. These rooftop decks can now be designed to perform a wide range of tasks in the same space – keeping the building dry, providing stormwater manage- ment functions, and providing enhanced living and working environments. Hydrotech has solutions to create all of this and we are proud to be a part of this evolution in building and environmental design," she says. Nedlaw Living Walls is participating in a very exciting program that firmly establishes the importance that green walls and roofs have in today's built environment. The Living Architecture Performance Tool (LAPT) – intro- duced last year by The Green Infrastructure Foundation – is a result of more than five years of research and consultation work. LAPT is a first-of-its-kind rating system and resource for designers wanting to incorporate green roofs and walls. Its primary goal is to certify that buildings with green roofs and/or living wall components are planned to achieve certain measurable performance benefits, so that they can be funded, designed, installed, and maintained with a much higher degree of confidence. "We became involved in the LAPT program through Diamond Schmitt Architects and Wight + Company, two firms that we have worked with on multiple projects. We've been invited to participate in two LAPT pilot projects, the first is Holy Blossom Temple in Toronto, Ontario, and the second is Adlai E Stevenson High School in Lincolnshire, Illinois," explains Laura Kennedy, technical lead at Nedlaw. "Because our living wall is an active biofilter, its impact far outreaches static plant walls in terms of measurable benefits – so they're a natural fit for the LAPT program." The Holy Blossom Temple features an incredibly impressive Nedlaw living wall biofilter that is 16.5-feet wide by 32 high. The Adlai E Stevenson High School has two Nedlaw biofilters that are 22-feet wide by 26-feet high. In addition to these pilot projects, Nedlaw continues to push the boundaries of living wall biofilter applications. The company is currently in the construction phase of the world's first known biofilter being used as a post-filter – meaning filtering air as it exits a space. This exciting project involves a series of living wall biofilters built into a parking garage at the Capitol Crossing development, Washington D.C.'s first eco-district. "Our biofilters will eliminate a portion of the car exhaust fumes," says Kennedy. "So, these eco-chimneys will help ensure that the surrounding public areas have improved air quality, given the proximity to the garage." A Northwestern BioMedical Research Center Blue Roof, Chicago, IL. Holy Blossom Temple, Toronto, ON.

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