The Rationale for Sustainable Building Design
Green buildings are penetrating the construction industry because they marry the best methods in construction with efficient performance. Green building design satisfies the building owner through its performance as it addresses sustainability concerns of economic, environmental and social impact. In addition to being cost effective, sustainable building design ensures minimum negative environmental impact through to the end of a building life cycle.
Sustainable building design provides a practical response to issues of environmental impact. Sustainability is not limited to a building construction stage; it encompass the entire life cycle of a building; from the extraction of resources to the time the building is demolished. Sustainable building utilizes renewable sources of energy; it encourages recycling and reuse of water and materials. Outside the building, it integrates the use of both local and adapted species for landscaping. Sustainable buildings design encourages efficient energy consumption by enabling passive heating, cooling and ventilation. The protection of the environment and efficient utilization of resources forms the foundation of sustainable building design.

Green buildings are substantially expensive at the design and construction stages; it requires the installation of sophisticated heating and cooling systems. However, these equipments are efficient; for example, energy-conserving lighting cost more than conventional, code-compliant lighting but it has superior cost saving benefits. Sustainable building design encourages the harvesting of rain water, which is used for irrigation; rain water harvesting requires the installation of additional piping, pumps, controls, storage tanks and filtration components. Owners of green buildings will recoup their investment in a short time because energy and water rise due to diminishing supply and increasing demand. Therefore, green building design has massive economic advantages than conventional building design.

Both conventional and green buildings design have potential effects to occupants; these effects can either be positive and negative. Green buildings design has more positive effects than negative effects. An estimated 30 percent of conventional buildings report complaints related to indoor air quality, which, may result in illnesses. This happened because conventional building designers paid little attention the impact of building designs on the health and general productivity of occupants. Green buildings are designed to promote the health of occupants. For example, green building contractors protect ductwork during installation to avoid contamination during construction; they use finishes with low volatile organic components to prevent poisoning by hazardous chemicals. When it comes to heating and cooling, they carry out precise sizing of heating and cooling components to ensure the correct humidity, and they use ultraviolet radiation to kill mold and bacteria.

The emphasis in green building design is the quality and characteristics of a building. Green buildings are healthy buildings built using resource efficient principles and methodologies. They are built to achieve better energy, economics and environmental performance. A multidisciplinary team must be sought before construction of a green building begins; this team includes architects, engineers, specialist in indoor air quality, landscapers and many others. Sustainable building design requires the input of experts in any field which will affect the occupant. Sustainable building design plays a role in minimizing the impact of buildings to the environment.
