A new generation of ambitious projects is aiming for full sustainability and nothing short of a revolution in green design in North America, and a large part of the inspiration behind his trend comes through the US Green Building Council’s new Living Building Challenge. Dr Paul K Hatchwell reports
To achieve the new certification, launched in November 2006, buildings are expected to meet all 16 sustainability criteria stipulated, achieving full sustainability in the built environment rather than being merely “less bad”. To this end, the USGBC has been developing a Living Building User’s Guide.
Up until now, no building has yet fully met the challenge, though many projects have achieved several of the criteria. However, there are currently five noteworthy projects in progress, including one slated for Vancouver by Stantec Architects, joined by at least four other projects already in the pipeline across North America, including three in Portland, Oregon, and classrooms at Cambrian College, Sudbury, Ontario, with design nearing completion.
Dual approach
The LBC has two categories. The ‘most realizable’ category looks at the best practicable design within budgetary constraints, while the ‘most visionary’ category is intended to encourage a more radical approach in thinking, stimulating debate on future design concepts.
The prerequisites cover six categories, including Site Design, Energy, Materials, Water, Indoor Quality, and Beauty & Inspiration, and are performance-based rather than prescriptive.
A key criterion is that of ‘net zero water’, in that annual water consumption must be derived almost entirely from rainfall falling on the site itself, treated entirely on-site, with any municipal supplies imported balanced by equivalent exports.
The criterion of ‘net zero energy’ stipulates that the building must generate most or all of its own energy, balancing occasional imports with sales of excess power to the grid.
Other criteria include avoidance of pollution generation and protection and enhancement of the local ecosystem.
The challenge is an initiative of the Cascadia Region chapter of the US Green Building Council, to which British Columbia is affiliated. It has since been endorsed by the Canada Green Building Council.
The USGBC established the now widely used LEED rating system for sustainable building, with LEED Platinum rating considered the highest.
However, the aim now is to raise the bar and go for full sustainability where possible, taking advantage of advances in building design, modelling tools, materials, and cost reductions in renewable technologies since the LEED system was established by USGBC in 1999. The council aims to integrate lessons learned into its forthcoming LEED Platinum Version 3.0.
Winners
The winner of the first LBC ‘most realizable’ award in May 2007 was Perkins + Will, founded in Chicago in 1935, with more than 60% of its 1,200 employees as LEED Accredited Professionals. It claims the highest number of any design firm in North America.
Their State Office Building boasts a double-skin façade, acting as a buffer against the highway, cutting out heat, pollution and noise, with energy production, water treatment and reuse, and natural ventilation.
The ‘most visionary’ award went to Mithun’s Centre for Urban Agriculture in Seattle. The centre features 318 housing units, with 35,000 square feet of solar PV, rainwater capture, filtration and storage at various levels for planters, gardens and for terraces, “farm fields” combining lab space and classroom as a learning centre, chicken farm, with additional food production through greenhouses and roof gardens. The building would provide habitat, farmland and other open space, complete with restaurant and café serving urban-grown food.
The Stantec team entry, winning second place in the ‘most visionary’ category, focused on a 7-acre contaminated site in Vancouver in need of regeneration. The design concept includes 16 residential, light industrial and commercial buildings. Apart from water and energy autonomy, the design includes provision for recycling of waste from kitchens and restaurants for composting, generating a surplus of energy for sale, heat, soil and fuel for transport.
The team intends to avoid demolition of existing warehouses, instead retrofitting them with energy-efficient systems including photovoltaic panels and recycled glass. The skin of the building would both collect water and act as a ventilation system. The project has also been commended for its employment potential in a densely populated urban area, near rail links.
www.cascadiagbc.org
www.perkinswill.com
www.mithun.com