Green
Design Process
The
process of green building design and construction is fundamentally
different from current standard practice. Time after time, successful
green buildings result from a design process with four critical features.
Commitment
to stringent health, ecological, and resource use performance targets
by developers, designers and builders. Measurable targets challenge
the design and construction team, and allow progress to be tracked
and managed throughout development and beyond. Post-occupancy evaluations
are often used to demonstrate performance of ambitious targets, to
help market the project and to inform future efforts.
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collaboration by multi-disciplinary teams, from the beginning of conceptual
design, throughout design and construction. Health, resource and ecological
issues inherently cross professional boundaries, requiring specialized
information and skills. Typically, the design team is expanded to
include new members, such as energy analysts, materials consultants
or lighting designers and cost consultants; often, contractors, operating
staff and prospective occupants are also included. The expanded design
team provides fresh perspectives and approaches, and feedback on performance
and cost. The design process becomes a continuous, sustained team
effort from conceptual design through commissioning and occupancy.
Computer
energy simulations assess energy conservation measures early and throughout
the design process. The expanded design team collaborates early in
conceptual design to generate many alternative concepts for building
form, envelope and landscaping, focusing on minimizing peak energy
loads, demand and consumption. Computer energy simulation is used
to assess their effectiveness in energy conservation, and their construction
costs. Typically, heating and cooling load reductions from better
glazing, insulation, efficient lighting, daylighting and other measures
allows smaller and less expensive HVAC equipment and systems, resulting
in little or no increase in construction cost compared to conventional
designs. Simulations are used to refine designs and ensure that energy-conservation
and capital cost goals are met; and to demonstrate compliance with
regulatory requirements.
Design
alternatives are evaluated on the basis of reduced life-cycle cost,
as well as capital cost. Design alternatives are aimed at minimizing
the buildings’ life-cycle cost – not just the lowest construction
cost. Assessments include costs and environmental impacts of resource
extraction; materials and assembly manufacture; construction; operation
and maintenance in use; and eventual reuse, recycling or disposal.
Computer energy simulation is one tool used to incorporate operational
costs into the analysis; other computer tools (cited in the Recommended
Practices that follow) are also available to help perform life-cycle
cost analysis.
This
process involves deeper analysis than is typical of traditional design
practice, and requires more effort from design consultants. Design
fees for this additional work typically reflect the increased work
involved, but the investment is small compared to the environmental
and cost impacts over the life of a typical building.
