A green building is a high-performance property that considers and reduces its impact on the environment and human health. A green building is designed to use less energy and water to reduce the life-cycle environmental impacts. This can be achieved through better design, material selection, construction, operation, maintenance, and possible reuse. Green buildings are part of a global response to increasing awareness of the role of human activity–especially real estate construction–in causing global climate change. Buildings account for more than 40% of all global carbon dioxide emissions which in turn lead to global warming.
Green buildings promote environmental conservation in the following ways;
They ensure selection of appropriate sites and environmentally sustainable site development: for instance; locating projects on sites away from wetlands, prime agricultural land, or reserves for endangered species.
Other environmental conservation measures include: minimizing parking to discourage excessive auto use; providing low emission vehicles and car sharing arrangements; provide infrastructure for public transit and bicycles.
Green buildings promote efficient use of water resources: This considers aspects like; controlling irrigation water use for landscaping; alternative ways to reduce sewage flows from a property and possibly treating wastewater onsite; Use of water conserving fixtures in building like sinks with water stopper basins to reduce water demand.
Conserve energy, use renewable energy and protect atmospheric resources: This considers aspects like reducing the energy use of buildings by 20% or more below the level of a standard building; using onsite renewable energy to supply a portion of the building’s electrical and thermal energy needs like the use of solar photovoltaic panels and solar water heaters; Installing monitoring devices to keep track of energy use; Reduce use of ozone harming chemicals in building refrigeration and air conditioning systems; Many refrigerants, such as chlorofluorocarbons (CFCs) damage the ozone layer.
Conserving building materials, reducing waste, and sensibly using natural resources: For example, installing recycling bins; reusing existing building materials that are still structurally sound; Use of locally accessed materials to cut transportation impacts associated with exhaust from trucks.
Green buildings provide and enhance indoor environmental quality: This can be done by; Providing increased natural ventilation for indoor work areas to increase the amount of healthy air inside the building. Green buildings also provide adequate daylighting of interior workspaces using vision glazing and overhead light sources like skylights and roof monitors (vertical glazing). This cuts down power expenditures on lighting.
It should be remembered that a green building isn’t a physical building, but rather green building refers to the characteristics of any particular building that makes it a green building. Any building can be a green building. Take the image below as an example of a green building.
Components; 1 Automatic opening windows linked to the environmental control system; 2 recycled bricks; 3 external glass louvers; 4 ventilation stacks linked to the natural ventilation system; 5 glass blocks reducing solar gain but allowing natural light in; 6 stainless steel chimneys; 7 high insulation value roofs; 8 photovoltaic panels.
It’s the individual elements of the building that makes it a green building.
One might ask, Is it that one green feature makes a building a green building, for example; the extensive use of recycled or low-impact materials in construction, means that the entire building is green? Similarly, could a building in which all features but one are green, for example, a green building where there is over-reliance on private car use, still be considered green?
Various aspects make a building green. That is; construction materials used, energy efficiency, and ventilation among others. No single aspect makes a building entirely green, but rather the level of ‘greenness’ of a building can be assessed by taking into consideration all the properties that make it green.
Several assessment tools have been developed to asses green building developments. These tools were developed to evaluate and compare the merits of green building design. Building assessment systems score or rate the effects of a building’s design, construction, and operation, among them environmental impacts, resource consumption, and occupant health.
These include Leadership in Energy and Environmental Design (LEED, United States), Building Research Establishment Environmental Assessment Method (BREEAM, United Kingdom), Green Building Council of Australia Green Star (GBCA, Australia), Green Mark Scheme (Singapore), DGNB (Germany) among others. All these green building assessment tools are voluntary rather than mandatory. The assessment is undertaken by accredited professionals that are commissioned by the green building council. These assessment tools provide independent third-party certification of the assessment of the sustainability performance of individual buildings, communities, and infrastructure projects.
BREEAM for instance, third-party certification involves the checking – by impartial experts – of the assessment of a building by a qualified and licensed BREEAM Assessor to ensure that it meets the quality and performance standards of the scheme. The BREEAM ratings range from Acceptable (In-Use scheme only) to Pass, Good, Very Good, Excellent to Outstanding and it is reflected in a series of stars on the BREEAM certificate. BREEAM measures sustainable value in a series of categories, ranging from energy to ecology. Each of these categories addresses the most influential factors, including low-impact design and carbon emissions reduction; design durability and resilience; adaption to climate change; and ecological value and biodiversity protection.
BREEAM includes the following measures:
Management: includes the planning of the project, and how effectively it considers the longevity of the building, its occupiers, and how well the wider stakeholders are involved.
Health and wellbeing examine how well the occupants are kept safe, secure, and warm, but also include acoustics and air quality management.
Energy: considers not only the reduction of energy and the minimizing of embodied carbon in the design process, but also looks at the efficiency of the services installed.
Transport: involves integrating the building into public transport networks as well as the provision of cycling facilities. Limiting the car-parking facilities is encouraged.
Water: includes consumption, but also looks at how well this is managed and monitored, including how well leaks are dealt with.
The other aspects considered include construction materials used, waste management, innovativeness of design, and pollution capacity.
In conclusion, The concept of green building alludes to the aspects of a building that makes it sustainable and environmentally friendly. Rather than having one particular building and calling it a green building, any building can be a green building depending on the aspects that make it sustainable and environmentally friendly (Though some buildings are greener than others).