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architects in BC

Archinature – architecture inspired by nature By Loghman Azar Nature is similar to a silent partner. While it provides us with an abundance of resources — the sun, air, earth and rain — it’s up to us to use them to save energy and create sustainable buildings and cities. This is not only good for the environment but makes economic sense. However, a new vision is needed to change the conceptual and physical separation that exists between man-made cities and the natural environment. Recognizing cultural and perceptual imperatives, ArchiNature — a holistic fusion of architecture and nature — makes meaningful use of natural resources while creating defining architectural works. It combines art, science and technology with the goal of achieving selfsufficiency. Each building is designed to operate like a small natural power generator, enabling an entire city to produce its own energy. This, however, is impossible if buildings are designed in the conventional manner. Fresh approaches and innovative designs are required. ArchiNature focuses on problem solving, making sustainability possible through its two-tiered approach. The first tier, demandreduction, is aimed at reducing a building’s footprint, energy and materials consumed and the production of emissions and waste — all of which negatively impact nature. The second tier, nature-rich, employs strategies to enhance cities’ relationships with nature and

increase power generation from clean, renewable sources. These strategies are employed to achieve a positive net state in cities’ partnerships with nature — a net state that is important to people, economy and nature, commonly referred to as the triple bottom line.

net-state-design Net-state-design is similar to limit-state-design used in structural engineering but it applies to the whole building. This approach is inspired by examples in nature where everything is made for a purpose using apposite amounts of energy, materials and processes. The various architectural solutions deployed under net-statedesign fall into two general categories: common-tech, which refers to centuries-old solutions and sometimes called passive systems, and hightech. The goal is to determine the right combination of architectural solutions to best create a positive net state. With computer modelling tools, each solution may be analyzed for feasibility under demandreduction and nature-rich strategies. Common-tech solutions under demand-reduction strategies are first employed for natural system applications, such as natural ventilation, daylighting, thermal controls, solar gain and earthing. The goal is to develop buildings that demand fewer materials and less space and The Applied Computing and Engineering Sciences building at Fleming College in Peterborough, Ont., is designed to transform the school into a leading edge learning-centred college. Environmental concerns guided LINE Architects Inc. in designing an architecture that goes beyond the conventional approach and is full of innovative solutions for an energy-efficient building. 1 Exhausts for warm interior air. 2 Intakes for cool fresh air. 3 The Galleria, a main circulation spine, allows natural ventilation, daylight and the connection of existing and new buildings. It also creates a space for informal learning and interaction among students and faculty. 4 The existing building’s exterior wall is converted into interior use, reducing heating and cooling loads in both buildings. 5 Natural light is provided through the use of skylights and clerestory in corridors and windows in every room.

Photo courtesy Loghman Azar

6 Natural materials, such as wood, metal and stone, are used throughout.

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7 Thermal chimneys positioned at the perimeter of the buildings to work in conjunction with the Galleria and assist in natural ventilation. 8 Double-glazed Low-E glass with thermally broken window frames. 9 Conservation of the tree line and ravine.

DESIGN QUARTERLY | Fall 2008


architects in BC

energy for heating, cooling, ventilation and lighting. These items require no extra initial cost and can even save on construction costs. High-tech solutions for power generation, such as photovoltaic, wind turbines, geothermal and bio-fuels from the sun, wind, earth and other clean renewable sources, may also be used to develop a net-zero energy building. To achieve net-state-design, high-tech and capital intensive solutions may be introduced when common-tech solutions have only marginal benefit or become ineffective. While some advanced technologies, such as double envelopes, photovoltaic and wind turbines, require additional investment, others provide acceptable payback given a building’s lifecycle operating costs.

bioclimatic zones Understanding the specific bioclimatic conditions of a location is a prerequisite in ArchiNature and is needed to develop a naturally lit and ventilated building. For most areas, weather data, direction of winds and sun angle information for different latitudes is readily available. Tapping into natural energy can be as easy as capturing the warmth of low-angled winter sun and redirecting the heat of high summer sun. Buildings filled with daylight and fresh air are not only healthier but more pleasant environments, particularly in northern climates. In hot climates, shading and shielding from the sun is more critical as is ventilation in humid climatic zones.

natural ventilation Conventionally designed buildings often use fans to deliver air and exhaust, requiring extensive ductwork and ceiling space. Based on the convection method of heat transfer, conventional mechanical systems are designed to mix and churn inside air to maintain a uniform temperature. For this system to properly work, more fans and diffusers are needed to force air (typically supplied from above) into rooms at high velocity. This has inherent waste potential and does not permit natural ventilation. Significant savings are possible by eliminating or reducing fans and replacing traditional mechanical systems with natural systems that work efficiently and quietly. For example, in buildings outfitted with a radiant system, heat is delivered at a lower level, lower velocity and at a lower temperature. This permits air stratification whereby warm air rises naturally and slowly, reducing the cooling and heating demand load. A combination of architectural elements, such as operable windows, clerestory, sky vents, thermal chimneys, sunspaces, dome, atria and gallerias, are also required for natural ventilation. Whereas ‘skinnier’ buildings, particularly those with linear forms and smaller skin-to-core dimensions, lend themselves to natural ventilation and daylighting, wider buildings do not. As a result, circulation networks are necessary and can also be used for air distribution as well as to bring in air and light. Larger rooms can be placed on single loaded corridors to facilitate hybrid cross ventilation from proper windows on both sides. Prevailing winds and solar energy can also be used to facilitate and induce natural ventilation in buildings.

daylighting Buildings filled with daylight are not only more energy-efficient but joyful places to reside. Additional energy savings may be obtained through proper placement of windows, skylights, clerestory and solar control devices. Sunshades and light shelves are also effective, so long as the sun angle is taken into account (for best orientation of exterior walls) and heat gain and glare problems are addressed. For example, on a south facing wall, a two-foot overhang in Toronto will have relatively the same effect as a four-foot overhang in Vancouver.

thermal massing Concrete, heavy timber, stone and brick walls store heat during the day, assisting in cooling the building, and release heat at night. Thermal massing is possible in most climatic zones, however, interior structural components should be left exposed. This is also a good way to save on

construction costs as it eliminates substantial interior claddings and finishes. However, attention should be given to acoustic design when hard surfaces are exposed inside.

building program To create a sustainable program and directives for designing purposeful spaces and building forms, it is important to consider the environmental aspects of a building at the outset of the project. Natural ventilation, daylighting and thermal massing solutions should be considered in the programming and included in the design. Adding them later is more difficult and less cost-effective. Architectural design elements, such as operable windows, gallerias, atria, skylights, thermal chimneys, clerestories, domes and roof gardens, are all important considerations during programming. Thermal comfort relative to ambient temperature and indoor air characteristics can be matched to specific needs rather than general standards.

site conditions While all buildings impact land, blending buildings into their surrounding environment mitigates disturbance to ecosystems and creates sites that are harmonious with nature. Further attention to building orientation (in relation to the sun and prevailing winds) provides better opportunities for solar heating, natural ventilation and daylighting. Building facades can also be situated on the sunny side or shaded side (as desired). Depending on the direction of prevailing winds, the building form and roof shape may be designed to assist with fresh air supply and natural ventilation. With urban sites, the impact of other buildings on shading and air movement should be taken into account.

landscaping Landscaping water features may be designed for evaporative cooling. Rainwater collection and reuse has additional advantages. So too does rain gardens, which help control the quality and quantity of storm water runoff. Deciduous trees act as sunshades in summer and permit winter sun to heat the building. Evergreen trees provide protection from afternoon sun on the west side of the building year round.

waste and nature There is no waste in nature. Everything is part of the ‘feedback loop’ of generation, transformation and regeneration. While the notion of cradle-to-grave has led manufacturers to create disposable goods, many manufacturers are beginning to adopt cradle-to-cradle principles. Based on the natural model of birth, transformation and rebirth, manufactured goods are now being recycled and reused thereby reducing and even eliminating waste in building construction and operations. In Stockholm, for example, the city converts all its garbage to electricity.

growth strategies Just as trees shed leaves to create new foliage, truly sustainable buildings are those that can be updated by new technology. Developing a balanced growth strategy for cities that is harmonious with nature is the primary objective of ecological urban design. It is about fusing key generators, such as streets, architecture, blocks, transportation and neighbourhoods, together and weaving natural patterns throughout to create a sustainable city. Our relationship with nature and the way we design and build our environment are crucial to the next generation. Loghman Azar, B.Sc., B.Arch., M.Arch. UD, OAA, MAIBC, is an urban designer and award-winning architect based in Vancouver. A partner with LINE Architect Inc., Loghman co-authored a research book on sustainable architecture in 1998, and is a speaker on sustainable architecture at conferences and colleges in Canada and abroad. Contact him at Loghman@LINEarchitect.com. Fall 2008 | DESIGN QUARTERLY

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Design Quarterly Fall 2008  

"Archinature - architecture inspired by nature" was written by Loghman Azar and published in this issue of Design Quarterly in fall of 2008...

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