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Things You Need to Know About Green Design

By: Terri Meyer Baoke

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Originally published in OAA Profiles, 2009.

THE ADOPTION AND MARKETING OF ratings systems, such as LEED™ and Green Globes, seems to be pushing green building to adopt a checklist approach to design. Although the green certification of a project might indeed ask that a checklist be submitted, to approach the problem in this way will shortchange the overall success of the environmental nature of the design. Tacking on photovoltaic (PV) solar panels and sun shades, or simply substituting waterless urinals to achieve a few points will not contribute to the overall eco-effectiveness of the solution. Nor will it improve the Life Cycle implications of the project. When 7% of the project’s design costs have been spent, 85% of the Life Cycle costs have been committed. The first decisions are the most important ones.

Sustainable design needs to be considered  in  a  highly  holistic  way, starting with the selection of the SITE. The selection of the site, the orientation of the building, and deciding on the shape, massing and material nature of the building are critical to initiating a successful environmentally-focused project. Design must always begin with considerations of the local climate, and progress to include site specific issues related to the specifi c microclimate. This site specific climate, within the same eco-region or city, can vary as a function of the relationship to green spaces, trees, water, pavement and other buildings. Urban environments are of particular issue as overshadowing can easily result, which may make some environmental design practices less effective. Proximity to other buildings can not only reduce the effective use of the sun for either solar heating or daylighting, but can alter wind patterns, making natural ventilation less possible. Urban environments are potentially noisy and polluted, again affecting the design of the building envelope and impacting decisions to use natural ventilation strategies. 

Relating the site to issues of ORIENTATION and MASSING  will  begin  to impact the way that programmatic requirements may be accommodated in the building. Certain uses may be able to take better advantage of passive heating and cooling if they are located according to site and exterior landscaping characteristics. daylighting can greatly assist  in  reduc ing  energy  costs  as well as provide a higher sense of well being to the occupants. The consideration of local site conditions may help to determine the placement of daylit versus non-daylit or service spaces. The CROSS SECTIONAL CHARACTERISTICS and BUILDING HEIGHT may also need to be modified to feed into lower energy, natural solutions. Synergies may  be  possible  when  looking at spaces that have larger mechanical or cooling requirements, where waste heat may be able to be used to provide heat transfer to atria or circulations spaces that can make do with a lower level of constant comfort.

Issues such as these are easy to  make  at  the  beginning  of the process, but become increasingly difficult and disruptive as the process unfolds. This is even more true  when  attempting to get more out of sustainable and energy efficient initiatives and systems, as they are intrinsically linked to issues of siting, massing and orientation.

In the IDP method of design, the client takes a more active role in initial design investigations as  some  of  the  proposed  ecological improvements may impact the overall goals for the project itself.  Many ideas may be tied to capital budget restrictions, but may result in lower long-term operating costs. Quick and iterative rough costs are also useful at the early stages of design in order to properly assess the potential of various design suggestions. Rough energy analysis can help in deciding the benefit of changes in building form or materials. If user groups are also involved, it is  more  likely  that  the  building can succeed once constructed, as the occupants will have a better understanding of building operations that may be key to energy efficiency or sustainable practices. The architect’s role changes from “form-giver ” to team  leader  as  the many ideas that can contribute to the sustainable nature of the project are incorporated into the overall conceptual design. The IDP promotes the creation of a sustainable base concept and building design  that  w ill  be  better  able  to respond to a range of additional criteria  as  might  be  required  if designing to LEED™, Green Globes or another rating system.

Once the concept and form of the base building has been reached, the decision about which additional green elements or systems can play into the overall Integrated Design Process can be made. The initial design decisions regarding siting, site treatment/landscaping, orinientation and massing should have netted both lower energy costs as well as provided opportunities to include the additional features that can be effectively and holistically incorporated into the base building. A  holistic  design  with  an  ecoeffectively designed base building that carefully integrates elements such as photovoltaics, sun shading devices, overhangs, light shelves, natural ventilation and special glazing to enhance daylighting, and that has had IDP related client involvement throughout the decision-making and costing process, will be less likely to suffer the “value engineering” removal of its sustainable systems – particularly those that might make a “features list.”

Terri Meyer Boake, BES, B.Arch, M.Arch,  LEED  AP  is  a  member  of  the OAA Sustainable Built Environments Committee and is an Associate Director at the School of Architecture, University of Waterloo.