The increase of fuel costs in 1970’s along with the concern for environment kindled the awareness and encouragement towards Green Buildings. Architects and ecologists started looking for solutions like reflective roofing materials, triple-glazed windows to achieve energy savings. But with the decrease of fuel prices, the Green movement was slowed down and did not receive much encouragement. It was later in early 90’s that the movement got kick start and awareness began to spread about need for sustainable buildings. An official Green home building program started in Austin, Texas in 1991. The movement has gradually gained momentum since then and we can now find significant changes in the newer buildings.
Sustainable Site Selection
There should be easy availability of public transport and conveniences so as to cut down energy consumption for transportation. A suitably selected site thus gets the benefit of mass transit.
Also, rehabilitation of sites damaged by environmental contamination is a better option than any new piece of land where large amount of energy and resource is needed to make the land worthy of building on. Rehabilitation thus saves large amount of energy.
Already existing landscape, soil and natural features should be protected. For this reason, hard paving on the site should be avoided to preserve top soil and ease rain water harvesting. There should be minimum storm water runoff.
Material and Resources
Sustainable construction material are chosen keeping in mind various characteristics like zero or low toxicity, high recyclability, zero or low off gassing of harmful air emissions, durability, reused and recycled content, sustainably harvested material.
Dimensional planning and other material efficiency strategies are used to reduce the construction costs. Construction and demolition material can be reused and recycled for e.g. inert demolition material can be used as base course for landfills. Proper planning for managing materials through deconstruction, demolition and construction is done. Efficient planning of utilities to minimize Utilization of rapidly renewable materials, such as bamboo flooring, wool carpets, strawboard, cotton ball insulation (made from denim scrap), genuine linoleum flooring, or poplar oriented-strand board (OSB). Using rapid renewable helps reduce the use and depletion of finite raw material.
Use of materials that are available locally is preferred over materials that need to be brought from distant places. It saves transportation costs. Also, alternative materials that can be generated from waste with lesser energy is used over conventional building materials.
For example, alternative materials for timber like MDF board, Mica Laminates and Veneers on composite boards should be used instead of natural timber. Industrial waste based bricks and blocks, aerated lightweight BPC concrete blocks, Phospho-Gypsum based blocks can be used for masonry structures. Fly ash, for bricks, outdoor paving and in concrete.
- Installation of water efficient or low flow equipments in kitchens and bathrooms to reduce water consumption.
- Incorporating waste water management technologies like dual plumbing for using recycled water in toilet flushing or using water conserving fixtures such as low flow shower heads, self closing nozzles on hoses, water closets with dual flush options.
- Use of Micro irrigation techniques at sites instead of high pressure sprayers.
- Recirculation system for centralized hot water distribution.
- For landscaping purpose, local plants and trees are used as they consume less water.
- Provisions for reusing and recycling water are made to ensure efficient water management.
- Using treated waste water, non potable water for site irrigation. Raw sewage can be recycled using aquatic plants like duckweed and water hyacinth to produce clean water suitable for re-use in irrigation and industry.
- Integrating Rain water harvesting system in building design to ensure maximum possible utilization of rain water.