1. Materials or technologies that are pricier than conventional ones, and likely won’t produce a return on investment within a reasonable length of time, but are used chiefly for the good of the natural or human environment. Some key features of Bison Courtyard and Cave Avenue Homes fall into this category. Each development has an enormous cistern and plumbing that collects rainwater for use in toilets and for on site irrigation. The build- ings will take less water from the municipal system, which gets it from the Bow River, so it means less pressure on the river. The cisterns will only pay for themselves in the very long haul, if municipal water and sewage costs were to rise substantially. ‘We think it’s the right thing to do’ says Poole ‘because the environmental constraint is the capacity of the Bow River’ to give water and receive sewage. For the same reason, Arctos & Bird has installed ultra-low-flush Caroma toilets from Australia, which are almost double the cost ($150-$200 more) of a conventional toilet, but which use a fraction of the water (3 to 6 litres, compared with 26 litres per flush). They are also making use of more costly composting toilets, and have installed a large industrial composter in the Bison Courtyard which will create rich soil for on-site landscaping. On Cave Avenue, the huge triple- or qua- druple-glazed ventilated (to prevent moisture buildup) windows in the residential units are made by VisionWall . They cost 50 to 75 percent more than conventional double- glazed, airtight windows but they won’t need replacing after 10 or 20 years; over the life of the building, they will pay for themselves. Both Banff projects use certified lumber from British Columbia for exterior cladding and other uses, at a premium of 10 to 25 per cent over conventional lumber. The payback is purely environmental; the fine-grain cedar is harvested sustainably and not from clear- cuts, which diminish forest biodiversity and can harm watersheds.
2. Green features or technologies that are cost-neu- tral: they cost virtually the same as conventional features and are also better for the environment. Interiors use low-VOC paint—paint that emits fewer volatile organic compounds— which improves indoor air quality. Envi- ronmentally friendly paints are now widely available and competitive in cost with conven- tional paints. At Bison Courtyard, heating and cooling equipment and commercial appliances use natural gas, not electricity, after analysis indicated this will result in a bigger reduction in greenhouse gases. The overall cost is about the same as conventional mechanical equip- ment and it will help Arctos & Bird toward its goal of a 20 percent cut in greenhouse gases over previous uses of the site despite a 10,000 ft 2 increase in floor space. The project’s retaining wall, exterior columns and landscaping all use rundlestone from the Bow Valley and supplied by a local quarry. It costs no more than comparable products, but the environment benefits because it isn’t trucked from afar. 3. Green products or technologies that are cheaper to purchase than conventional ones, and features integral to the building’s design that result in lower operating costs. Bison Courtyard uses concrete with a higher fly-ash content than usual. Cheaper than conventional concrete, it’s also more environ- mentally friendly and stronger. Retail spaces in the project are no more than 20 feet deep, with windows at each end. This reduces the need for electrical lights and heat during the day, and allows for the use of lower-wattage bulbs on overcast days. Similarly, windows in the residential units are placed to make the maximum use of available daylight, based on each unit’s orientation. In Cave Avenue, each open-concept unit is heated with a single gas fireplace and fan, eliminating the need for, and cost of, a fur- nace and ductwork. c
Christie McLaren is a freelance writer and editor specializing in the environment and natural resources. She lives in Canmore, Alberta.
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