Green building is the practice of creating and using more resourceefficient methods throughout the whole process of a building project – from planning and design through choice of materials, construction, operation, maintenance, renovation, and demolition. Green buildings reduce the overall impact of the built environment on human health and the natural environment (a) by using energy, water and other resources more efficiently than conventional buildings, (b) by creating healthier living and working environments, and (c) by reducing waste, pollution and environmental degradation. Green buildings also cost less to run than conventional buildings. Studies on the performance of green buildings have shown sustainable average savings of:

■ 13% lower maintenance costs
■ 26% less energy usage
■ 27% higher levels of occupant satisfaction
■ 33% lower carbon dioxide emissions.

Most green buildings cost slightly more (typically 2%) to design and construct than conventional buildings. However, when up-front costs are compared to life-cycle costs, there is usually a saving of ten times the extra initial cost – savings that arise from lower energy costs and increased productivity from those who work in green buildings.

Project owners who want structures to be designed and constructed on a green basis need some means of measuring ‘greenness’ and ensuring they are getting a green solution. Leadership in Energy and Environmental Design (LEED) is a third party certification programme to define and measure green building (see box).

Sustainability is the capacity of systems to endure. For human beings, sustainability is the potential for the long-term maintenance of well being, which in turn depends on the well being of the natural world and the responsible use of natural resources. LEED promotes a whole building approach to sustainability by recognizing performance in location and planning, site development, water
savings, energy efficiency, materials selection, indoor environmental quality, innovative strategies and priorities in regional issues.

LEED measures and enhances the sustainability of buildings by establishing metrics and rating systems to measure and recognize buildings based on their performance in the three main dimensions of sustainability: (a) society, (b) environment, and (c) economy. Projects certified under the LEED rating systems demonstrate that they have addressed the elements that enhance these three areas in a balanced way.

The LEED rating systems are tools a design team uses to ensure that it designs, constructs and accounts for a project’s green features properly. The LEED process ensures that the whole building process is value engineered from the start. There are nine different rating systems for the design, construction and operation and maintenance of buildings, homes and neighbourhoods.

These rating systems are continuously evolving in order to incorporate emerging green building technologies. The LEED green building rating system used on a particular project will depend on the nature of the project.

For example, the certification criteria for the new construction or the major renovation of a retail complex will be different than the criteria used to certify a new home or a neighbourhood. To achieve LEED certification, the project team (which must include all major players in the whole process) needs to study and document the tradeoffs inherent in their design decisions.

For example, installing solar energy panels entails a large upfront cost but will save money in the long run through energy savings. Vegetated roofs will add design and construction costs but will lower energy costs as less cooling will be required and, at the same time, the vegetated roof will enhance the environment by providing a habitat for local flora and fauna.

However, not all green criteria add significant cost; eg, light detectors to control the energy used on lighting and carbon dioxide detectors to adjust fresh air requirements are not costly to install. Under the LEED certification system, points are awarded across major categories of criteria such as site
sustainability, efficiency in the use of water and energy, materials and resources, and the quality of the indoor environment. The distribution of points over these categories will vary depending on the location of the project in order to take the local climate into account.

Certain prerequisites or minimum requirements have to be achieved before points are awarded. The number of points awarded determines the level of certification as follows:
■ Certified : 40–49 points
■ Silver : 50–49 points
■ Gold : 60–79 points
■ Platinum : 80+ points
Having a construction project LEED certified does cost time and money. However there are three reasons why project owners should seek certification: commitment, legitimacy, and marketability.
Commitment: by registering a project with the USGBC, the owner shows that he is committed to meeting the standards required by the appropriate LEED rating system for that type of project.
Legitimacy: LEED certification tells clients and the general public that the sustainable features of the project have been verified by a third party.

Marketability: LEED certification is a strong marketing tool. Several studies in 2008 found that, compared to conventional office space, higher rents could be charged for LEED certified office space which also had higher occupancy rates.

Construction companies worldwide are now aware that a capability in green building is becoming more important in their marketing efforts. By becoming the first green contractor in its markets,
KN will reap significant benefits as the demand for green building increases.

However this will require a skilled workforce that is knowledgeable about environmentally friendly technology and motivated to search for new and more cost-effective ways to achieve the
goals of green building. KN Engineering Services Department (ESD) now has the knowledge and
experience to design green buildings and to undergo the LEED certification process. ESD offers guidance and study material to any KN colleague who would like to sit for the LEED certification examinations as LEED green associates or accredited professionals (see box).