Building a green house

Building a 'green' house

How to incorporate features in your house that reduce environmental damage. Join the many Bangaloreans who are already doing this.
By Chandrashekar Hariharan
23 Mar 2008 Print | Email | Comments (0)

Human excesses have caused significant environmental damage over the past 100 years. We now need to find ways to reverse this trend or use efficient, natural-resource management that enable efficiency while continuing conventional development objectives. One hugely significant element of this problem is that nearly 50 per cent of all fossil energy consumed in the world goes to just one industry: building. This understanding is essential if humans are to find effective ways of reducing the consumption of fossil fuel and the damage it causes to the environment. The concept of Green is as relevant to Bangalore as any other place in the world.

A T-ZED house

So, where can you start? For every energy manager, it is important that you think of a building from the point of view of your own need. Since most of us energy professionals are not strong in the domain of architecture or civil engineering, here is a primer that may help in directing the creation of a building. There are many features that you can incorporate into a building. You will be constrained by the fact that your thinking and your aspiration for some features may meet with either resistance from building professionals [because they have not done it before] or with reluctance [because they are not confident of taking responsibility for what is relatively new to them.

Design must recognize the ‘Four E’s’ of Ecological compatibility; Economics, Efficiency, Endogeneity and Equity. Architecture must adhere to a six-strand approach entailing integrated management of all aspects that relate to:
• Earth (avoid bricks that employ precious topsoil and use 400 deg C energy; use soil stabilized blocks)
• Energy (both embodied and active energy for consumption, while engineering active and passive elements for energy saving)
• Water (infrastructure approaches and plans that help communities grow their own water; waste water management)
• Waste (to ensure that communities of companies in an office block or of homes in a residential enclave assume responsibility for managing the spectrum from degradable to toxic wastes)
• Air (with passive cooling and active cooling systems that are energy efficient and ozone non-depleting)
• Biomass (to improve the microclimate of a land zone in a way that reduces demands on cooling).
Soil stabilised blocks

There are five main aspects to a house:

1. Plinth and Foundation - Before you get on with this you must ensure that you have made your final call on the size of your house and of every space you seek. To make any change after the foundation is done can prove to be difficult, or expensive.

2.The walls - There are many types of walls you can build. We recommend a functional blend of soil cement blocks, hollow and solid clay blocks, and molded concrete blocks. Of course, you know that the last of which is the most widely used building material for walls. In the world today, there has been a shift from these building blocks to materials that are a combination of pre-fabricated steel sections and gypsum board that is moisture-resistant and so can be used for external walls too. The architects will advise you on the elevations and profiles. Remember that the larger the openings for windows and doors, the higher are your costs.

3.The roofs - You can employ many types of roofs. Typically, they are -- hollow clay block roofs with pre-stressed clay channels or concrete rafters; pre-cast slab roofs with a thinner layer of screed concrete that uses minimum steel and cement is an effective way of making roofs; ferro-cement pre-cast slabs can also be used for flat and sloped roofs. For intermediate roofs or the top roof you are sure you are not going to build on, you could use double tiled roofs or singled tiled roofs with a grid in wood or steel.

4.The floors - Opt for material that requires very little energy in the making of it. For eg, natural stone is preferred to ceramic tiles which is highly energy intensive. The following are floor options which can lend elegance to your house: polished granite or natural stone slabs, terracotta tiles, Bethamcherla natural stone in different colour tones, Shahabad, Athanagudi (green and brown), machine sliced grey granite (polished or rough-hewn), polished granite in a few shades (a more expensive option), marble (also an expensive option). There are choices like sandstone which are unique, and add elegance but are expensive.

5.Windows and doors - You could avoid wood and save cost while being environment friendly. Go with metal frames that are available with lovely finishes these days, and at costs that are attractive. If you insist on wood, go with treated jack wood and neem wood. Another option is to buy antique doors and windows, and save on fresh wood purchase. If you can afford it, you can use wood for staircase treads and for flooring of small areas in your home and work spaces.

The Costs

When you work with an architect, please get a cost and quantities sheet with these five segments clearly marked out. There is great energy saving that you can effect if you paid attention to this critical aspect of a building’s creation and in the early stages. From here on, it is upto a professional contractor and careful supervision. Between the architect and you, this needs to be achieved just so to get the building the way you want it.?
Chandrashekar Hariharan
23 Mar 2008

The author is the CEO of Bio-Diversity Conservation (India) Ltd (eco-bcil), #5, Ali Askar Road, Bangalore – 52.

This article was originally published in the Feb 2008 issue of Sattva, an ITIHAS initiative and an e-magazine focusing on the social sector.