The Initiative for Green Habitats represents a long term commitment towards providing solutions for the creation of Sustainable Built Environments. This blog attempts to provide an insight to our views, commentaries on our work, ideas that we are working on, and provoke thought where there are more questions than answers.

Friday, September 21, 2012

Towards a zero footprint architecture

Our decisions hold the key to this 21st century environmental enigma.
Is it really possible to go 'zero'?

Consider this. Every act and process putting together a building nowadays involves huge amounts of energy and impacts the environment. Let us assess a few areas:
  1. Utilisation of materials to build- virgin, reused, recycled or otherwise
  2. Extraction of the raw materials
  3. The transportation of these materials
  4. The manufacture of building materials..
  5. The generation of direct and indirect wastes, and pollution.
  6. The consumption of materials in operations- water, energy, fuel, etc.

When we look back, not too long ago, say just over a 100 years, we find that there were hardly any emissions of any kind involved in the usage of materials for building. Energy for extraction, or the synthesis of materials involved the usage of higher degrees of human labour to compensate for any other form of energy. This was so stark that the construction of large institutional buildings like forts, palaces or temples resembled the efforts put in to build the dams of today. Having said that, in India we are still a labour intensive construction industry... which is not altogether a bad thing considering the great amounts of employment that it generates. What is required though is a drastic improvement in working environments and skill levels.
Surely some CO2 emissions and environmental fall outs did result from some construction activities (the institutional causing greater damage than the vernacular). For example, the burning of bricks used as building blocks has remained much the same as today, with vast amounts of wood/coal being used to fire the brick kilns. Sun dried bricks, or Compressed Soil Stabilised Blocks, or, rammed earth walls, using lime as a mortar, need no firing and use solar energy. If we are able to tap into renewable energy sources for construction or material production, we could make material production and usage emission free. 

An iron ore mine in South Goa that has eaten into the biodiversity rich Western Ghats!
Extraction is altogether a different matter. The energy of extraction today involves the spending of large amounts of energy for mining, excavating, etc. In earlier times, the low demand (non-institutional) dictated the rate of extraction, but a market driven new world economy exerts too much pressure here. To keep up the indices of performance, more material is extracted. I have written about this in another blog post. The methods of extraction have also changed significantly. Granite is now blasted out of the ground, while one method from the past used in some places even today , involved the insertion of wooden dowels into the ground and soaking them with water, which would expand during overnight cooling and crack the granite in the desired size. The extraction of stratified rocks like marble and sandstone has seen a similar change, with the inclusion of heavy machinery  against the use of skilled manual labour who would split the marble along its grain, by driving wooden/metal  wedges into the rock. Today, more often than not, vast areas of forests are cleared to reach these raw materials. This leads to the destruction of CO2 banks and the release of these green house gases due to the rotting of this cut-down biomass. Also, forests are sponges of the earth and ensure a healthy water balance, by keeping the ground well hydrated and holding together the top-soil. Once removed, the land gets parched and erodes the soil of essential minerals for sustaining plant life. Dependent fauna are the immediate victims. The massive scale of raw material extraction today has impacts that affect the region beyond the immediate context. I am not too sure if there can be a zero impact extraction method as an alternative, but perhaps we should look at the kind of raw materials that we consume as a start. A larger use of waste as a raw material, easily re-fashionable building components, a more spread out usage of material according to geographic regions might help.

With a booming modern day construction scenario, such sights aren't
that uncommon, but what is not visible to all is the energy consumed!
Today's building materials have often travelled many a mile to get to our construction sites. We do not bat an eyelid about this specially since all aspects of our lives have ceased to be limited by matters of distance. Being a relatively large nation, geographically speaking, industry has spread its tentacles close to their source of raw materials. Vast transportation networks and corridors constantly feed stocks close to our sites relentlessly. The effort to pick up these materials for construction is usually from the local outlets, obscuring completely the energies that go into getting those materials there from the points of manufacture. There are other forces that define the distances our building components travel...  Global aspirations of the project initiator may attract faucets all the way from Europe, or, kitchen equipment from Italy, or, Paints from Korea and so on. This very global economy sometimes also creates a seemingly  improbable yet financially lucrative incentive to by overseas.... a whole lot of building materials today (as many other goods) originate in China.
Over a 150 ears ago, such sourcing would have been the exclusive habit of the kings!! The masses would invariably build what was available locally, therefore more affordable. While it is easy to talk of the use of locally available material, we ought to compliment that with supporting market incentives, upgradation of skill-sets & technologies, and most importantly a sustained education and advocacy effort to sensitise people to the ills of stretching these geographic limits. A few disincentives like a transportation emission tax could provide an encouraging nudge. 

Manufacturing today is a complex science, involving complex systems, resulting in complex products.... and ever so often a set of complex (read harmful) residues/wastes. In the yearning for 'long-lasting' solutions we have taken complex engineering to higher and higher levels, and devised materials that are made of  unbreakable bonds. Be it the plastics that cater from protective sheeting to transparent screens, the laminates for flooring or cladding, the chemical veneers for roof and wall covering/protection, the non abrasive tiles that span our floors (and walls),.... the resulting side-effects are equally strong in their environmental impacts. High energies needed for manufacture of these complex bonds result in high CO2 emissions, Chemical by-products take a toll on our air, soil and water as emitted pollutants, and the products themselves end up leaching poisonous chemicals into their built environs over their lifetimes. For example, Volatile Organic Compounds like lead, Mercury and Arsenic are spewed by most chemically coated surfaces from paints to laminates to carpets. Bituminous compounds used in waterproofing (and in road tops) break up relatively quickly and leach into the ground, contaminating the local aquifers. Perhaps the trick is to stick to near natural states of materials, like earth for construction, bamboo/wood for building structures, lime/mud for wall plaster, stone as cladding and building block, etc. Physically fashioning a natural material to suit an application involves no further chemical contamination, whereas chemically altering compounds is saddled with these toxic extras.
The sun sets behind the smoke stacks of one of our many industrial backyards.
There are scores of materials today that claim to be energy efficient. But we have to put that in context. Energy efficiency in usage (while good) need not be energy efficient in manufacturing. Also, energy efficiency only implies a betterment from the current benchmarks, and does not mean that they are energy positive. Furthermore, when one refers to a zero energy building, a common term today, one normally means the net energy consumption during its lifetime, which does not include the energies that went into the making of the building and its building components. Depending on building use, the energy in building (or embodied energy of building) could be equal to the total energy consumption of the building in its operations. Thus the often used term for zero energy building refers mainly to the operational energy equation, and is not therefore truly zero energy.

I have covered the topic of consumption in an earlier post, and it takes very little to understand that consuming less would have a proportionately lesser footprint. So far, we have seen that we have big decisions to take in the choice of materials to reduce the upstream environmental impacts during extraction, transportation, manufacturing and utilisation. Is it possible to occupy a truly zero ecological footprint architecture? Many examples exist, in our past, in our rural hinterland and in some truly commendable contemporary projects, that hint at the fact we can get there. The necessary ingredient for that though is a complete overhaul of our thinking and gaining insights into our every decision in the building process, from design to occupancy. I remember a Star Trek episode which spoke of a race that chose a passive and low tech living against the high-tech unbridled alternative, for very much the same reasons... to preserve a way of life! 

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