For a thoroughly sustainable home

Navita Singh elaborates on what it takes to build a completely green home

One way by which you can contribute to the development of the environment is by constructing your home in an environmentally conscientious way. This can be achieved by opting for a sustainable design for your residence. A sustainable home utilises natural materials and simple construction techniques in such a way, that minimal damage is caused to the environment.

There is a perception that such homes are difficult to design and expensive to build. But in reality, you can easily create an eco-friendly home with careful planning and sensitive design. For achieving sustainability in your home, practise the simple philosophy of ‘Less is more’.

You need to plan for the present, as well as the future requirements. The design should be flexible enough to accommodate any change, without the need to undergo any remodelling or renovation later. Some important aspects that need to be considered while designing a green home are discussed below.

Traditional architecture

It would be extremely useful to go back and rediscover our rich vernacular architecture to adapt to our modern homes. Traditional building features like courtyard, chajjas (projections), verandahs and jallis (perforated wall) are extremely useful in providing shade and allowing air circulation. Employing these features in your home will considerably reduce the electric load for cooling and heating.

Mud, straw and lime have been used in vernacular architecture for centuries. Some organisations and individuals have made a commendable contribution in reviving and reinventing traditional features and techniques.  So, building a sustainable home will go a long way in conserving the environment in addition to providing you with a healthy and beautiful abode that is in harmony with nature.

Site, orientation & landscaping

Before beginning the design of a home, it is important to do a detailed site study. Try to preserve as many of the existing trees and topographical features. Maximise the open and unpaved green area on your plot so as to allow the percolation of rain to recharge the ground water, improve the air quality and regulate the ambient air temperature.

Not only does planning of landscaping around your home result in a beautiful environment, but it also increases the biodiversity. Choose those varieties of plants that use less water and require little maintenance.

Water efficiency

Rain water harvesting is mandatory for a sustainable home. Rain is the purest form of water; so, an earnest attempt should be made to use it for fulfilling your needs. Proper collection and filtration of this water can easily cater to your year-round requirement. Borewells should not be dug for your home as they deplete ground water.

Use efficient water fixtures like low-flow taps and showers, and dual flush cisterns. The use of showers and bath tubs should be limited. Washing machines that use less water should be installed. Avoid installing Reverse Osmosis units as they result in excessive water wastage. For every litre of purified water, three litres of waste water with very high salt content are generated. Effort should be made to reuse ‘grey water,’ which is the water from bathing, washing machines and dish washing. It can be used for flushing the toilets.

Materials

For a sustainable home, certain materials are more suitable than the others. There are certain characteristics of materials that need to be examined before making a selection. The embodied energy of the material should be low. This means that less energy should be used in manufacturing, installing and maintaining it through its life cycle.

High thermal mass is preferable as such materials provide better insulation. Try to minimise the use of materials that are from non-renewable resources. An attempt should be made to use recycled materials or reuse materials from old buildings and structures.

Locally sourced materials are a better choice as they are easily available, and economically and climatically more suitable. Reduction in the use of cement and steel will considerably bring down the carbon footprint of the home. Using filler slabs for roofing results in substantial saving of both these materials. Avoid using materials that release toxins during their life cycle. For instance, paints that contain volatile organic compounds (VOCs) release contaminants that are detrimental to health.

Bricks are one of the most widely used green building material all over the world. They possess high thermal mass and low embodied energy, making them a good choice for a green home. Materials like bamboo, cork and wood are extremely suitable for a sustainable home.

Wood is a comfortable material with a beautiful colour and grain that imparts an earthy touch to a home. Use wood and wood-based products that are FSC (Forest Stewardship Council)-certified to ensure that they are from a responsibly harvested forest. Try to use recycled wood or re-claimed wood wherever possible.

Use natural materials like stone, mud, lime, straw and rubber. Stone is an appropriate material for a green home as it is natural and durable, in addition to being available in a wide range of appealing colours, grains and textures. Ceramic tiles and linoleum can also be used in your home as they are made from natural ingredients.

It’s debatable if concrete is appropriate for use in a sustainable home. Made from non-renewable materials like cement whose manufacturing leads to the production of large amounts of carbon emissions. Otherwise, it’s a durable material that requires little maintenance and has high thermal mass. Glass is made from natural materials and is recyclable. Its only drawback is its poor insulating property. You can use double glazing to improve its insulation.

Energy efficiency

Ensure that there is sufficient daylight entering the home. Suitable orientation, appropriate window openings and sky lights will reduce the need for artificial lighting. Similarly, good natural ventilation and proper insulation will minimise the artificial cooling and heating requirements of the home.

Bengaluru is blessed with a good climate almost throughout the year; so, if it is a well-designed home, you will not feel the need to install air conditioners. In case you want to use air conditioners for a few months in peak summer, ensure that the windows have shutters that can open to allow fresh air when kept open. Make sure that all the appliances installed in the home are of a high BEE (Bureau of Energy Efficiency) star rating.

Solar water heating is an efficient use of the abundant and clean solar energy.LED lights are a greener option than compact fluorescent lamps (CFLs) as the latter contain harmful mercury. Photovoltaic panels can be used on the roof to produce electricity at home.

Maximum heat gain for a home is through the roof; so, by painting the terrace white, sunlight will be reflected. Also, lesser heat will be absorbed by the roof and transferred to the home. Using cavity walls and filler slabs for roofing protects the home from extreme external temperatures.

(The author is an architect and interior designer)