Green building focuses on environmental sustainability and the integration of natural resources into a structure. This is done by using a variety of nontoxic materials, such as recycled metal, concrete, compressed earth blocks, sheep’s wool, and lumber.
The concepts of Green building are broad and can be viewed from many perspectives. Educators can focus on specific themes to integrate with other curriculum topics.
Energy Efficiency
Energy efficiency is a big factor in green building. In addition to reducing waste and recycling materials, green buildings focus on using renewable energy sources to reduce the dependence on fossil fuels. They are designed to take advantage of natural light and ventilation, as well as to control heat gain and loss.
Many factors contribute to the energy efficiency of a building, including the shape and location of the structure, the amount of sunlight it receives, and the type of insulation used. Green builders are also encouraged to use a variety of methods for water conservation, such as rain gardens and reduction of stormwater runoff.
Research conducted by PNNL supports the development of new technologies that can help improve building efficiency, increase the integration of clean energy resources, and better coordinate electricity consumption within and between buildings and the power grid. This includes work to accelerate highly efficient solid-state lighting products into the market and develop innovative approaches for designing and deploying building controls that can automatically adjust operational functions according to predefined energy-saving adjustment parameters.
Water Efficiency
Green building practices focus on reducing the environmental impact of the construction process and the life cycle of the building. This includes using renewable energy, limiting waste and toxic materials. It also involves water conservation and the use of non-toxic plumbing fixtures.
The use of low-flow plumbing fixtures and a greywater system can save large amounts of water. In addition, green buildings can be designed to use rainwater and recycled wastewater for outdoor irrigation and toilet flushing.
Water efficiency is a key element of green building because only 3% of Earth’s water is fresh. In addition, wastewater can contaminate rivers, lakes and the water table with bacteria, nitrogen, metals and other contaminants. To protect the environment, green buildings are designed to minimize water pollution and reduce the amount of wastewater that is sent to municipal sewage treatment plants.
Green Star tools provide a best practice framework to achieve sustainability in the design, construction and operation of buildings, fit-outs and districts. They are supported by a range of green rating systems such as the Leadership in Energy and Environmental Design (LEED) System, BREEAM, and DGNB.
Indoor Air Quality
Unlike conventional structures, green buildings use non-toxic materials to ensure that occupants experience good air quality. In addition, they minimize energy consumption and reduce environmental impacts. They also feature ventilation systems that change out old air with fresh air to control temperature, remove moisture, odors, smoke, heat, dust, airborne bacteria, carbon dioxide and replenish oxygen.
Moreover, green buildings have air quality monitoring systems to ensure that occupants are protected from pollutants. These systems detect and control indoor pollutants at their source. They monitor and control the amount of VOCs, CO2, ozone, formaldehyde and particulate matter in the indoor air. They also provide occupants with air quality data through displays to improve human behavior such as investing in effective ventilation and avoiding products that release pollutants.
Since people spend 87% of their time in enclosed spaces, focusing on ensuring that the air is healthy is crucial for green buildings. The main goal is to improve occupant health and performance by reducing exposure to harmful indoor pollutants. However, it is important to note that not all technology solutions to improve IAQ in green buildings work as advertised.
Materials
Buildings account for about a third of all greenhouse gas emissions. Green buildings are designed to reduce these emissions by using renewable materials and by minimizing energy consumption.
Sustainable, nontoxic and recycled construction materials are often available at reasonable prices. These include low and zero VOC paints, strawboard made from wheat instead of formaldehyde-laced particle board, linoleum flooring made from jute and linseed oil, and soy-based insulation.
Other materials, such as gravel and permeable concrete that allow for the replenishment of groundwater, are also being used in green buildings. Plastic is also emerging as a viable green alternative to traditional concrete, because it is a recyclable material that can be produced without harmful additives or toxins.
Green builders also try to use materials that have a lower embodied energy, meaning the amount of energy required to manufacture the material. To this end, a variety of options are being explored such as self-healing concrete and alternatives to conventional steel and concrete mixes that utilize slag, production waste and recycled metal.
Environmental Impact
Using green construction methods reduces the negative impact that buildings have on the environment. With a holistic approach to their planning, design, construction, operation and maintenance, they minimize resource use while maximizing their benefits.
Green buildings reduce greenhouse gas emissions and conserve increasingly stretched energy, water and material resources. They also enhance occupant health and performance and support the surrounding natural environment.
The CII-Sohrabji Godrej Green Business Centre in Hyderabad, India, for example, a 20,000-square-foot building, uses 55% less energy than the average commercial office building of its size thanks to its green design and sustainable technologies. A solar array and a rooftop rainwater harvesting system provide the building’s electricity, while a daylighting system reduces artificial lighting requirements and a solar-powered water heating system cuts energy costs.
The occupants of green buildings can experience lower energy costs, better indoor air quality and improved work and sleep performance. For builders and developers, higher property values result from optimized resource utilization. In addition, green buildings are typically easier to maintain and last longer than traditional structures.