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! 

Kicking up Dust - Linking construction activity to health

A walk in the (dusty) clouds.... Where? Our fast growing cities!

It is high time that we give importance to health issues due to construction activities. The responsibility of professionals associated with the construction industry goes beyond the merits of the end product. The general well being of those who live and work within and beyond 'the site' HAS to be our responsibility. Look around you and all you see is apathy. Work being carried out with no concern for the fall outs.

Dust pollution has gone up visibly in our rapidly developing cities, and this is taking its toll on it's inhabitants. While it puts construction personnel at the highest risk, it is an increasing factor for the rise of respiratory diseases in our cities. A statistic by the Karnataka State Pollution Control Board puts construction generated dust pollution at about 14% of the contributing factors for Suspended Particulate Matter in the air. In the construction industry the most prevalent of these diseases are chronic obstructive pulmonary disease (COPD) and asthma and silicosis. However, chronic fungal infections (carried on dust), interstitial lung disease, silicosis which increases the risk of Tuberculosis, and even carcinoma have been stated as possible fall-outs of dust related health issues. This can be verified by a simple Internet search.  It is appalling that it has not yet become a topic of public debate.
The major contributors of dust are bad practices at construction sites, callousness of workers, unprotected storage of construction material & debris, shoddy maintenance and incomplete works. Movement of vehicles to and from  construction sites, and those carrying construction material and debris, without adequate checks like watering down at points of egress, cause further dust pollution. Transporting materials without proper covering  spreads dust way beyond the peripheries of the construction sites. If we identify these points of origin, we should be able to put in place checks to curb dust pollution.
A quick perusal of the Karnataka Pollution Control Board's website (could apply to other cities as well) shows a stark picture. For a city this large, only 6 points have any recurring statistics at all! This is hardly enough to draw a clear picture of the the extent of air pollution across the city, let alone construction related dust pollution. There seems to be no monitoring being carried out near major arteries where large scale construction projects are underway (metro, underpasses, flyovers, road widening/laying, etc). What we need is a more wide-spread and dynamic data gathering and sharing process of air pollution levels which can be monitored closely. This would also also enable the linking of pollution levels with specific activities, which can then be a support for taking action. While there are clear benchmarks for acceptable levels of emissions from DG sets for example, there don't seem to be any clear norms for what ambient dust levels should be for construction sites in specific. Broader SPM (Suspended Particulate Matter) and RSPM (Respirable Suspended Particulate Matter) figures are available, but none for points of origin (like construction sites) where concentration levels are much higher.
From roads to building sites, we see construction debris strewn about and a haze of dust. This haze does not restrict itself to the site and is spread by air movements to cover a wider area. This is evident in the browning of plants, and parked vehicles around the site, often beyond visible distance. While it is shocking to see construction workers working without protective gear, what is greater concern is the scale to which this problem has grown. 

Construction dust affects all of us in more than one way:

• Most importantly, it affects general health, leading to a slew of respiratory disorders, eye/throat irritation, etc.
• It causes damage to property
• It leads to environmental deterioration... air and water pollution
• It creates a poor quality of life and workplace... both basic needs of citizens

It is very surprising to see that precious little has been done to reduce this growing problem.The 'Polluter Pays' model has been discussed ad-nauseum in various fora, but dust pollution due to construction is limited to only a single point stipulation to exercise control in the bye-laws and earns one credits in one of two green certification for buildings in the country. Nearly all construction sites are devoid of even signage warning against the generation of dust, or, the wearing of adequate masks. A simple search on the 'AIR (PREVENTION AND CONTROL OF POLLUTION) ACT, 1981', (or its amendment) does not have the word construction or the word dust in it! Surprising. Here are a couple of definitions that caught my eye:

• "air pollutant" means any solid, liquid or gaseous substance 1(including noise) present in the atmosphere in such concentration as may be or tend to be injurious to human beings or other living  creatures or plants  or property or environment;  
• "air pollution" means the presence in the atmosphere of any air pollutant;  

Doesn't dust qualify as an air pollutant? And wouldn't construction be seen as a major contributor of dust pollution? On a single page document on the KSPCB website, termed as 'Measures to combat Air Pollution in Bangalore city' there is no mention of construction dust. Their entire pre-occupation is with types of combustion fuels. I think Pollution Control Board/s have to wake up and take notice of construction dust as a major contributor to respiratory diseases.

Here is what we think ought to be done:

1. Draw out a policy on construction related dust pollution. 
2. Make dust pollution a statutory offence. It does amount to serious negligence on the part of the executing agencies.
3. Clearly spell out the guidelines to be followed strictly at EVERY construction site and in ALL construction activities.(This is not that difficult. There are very clear processes, and measures that can be followed to ensure compliance. Of course this involves extra effort and a wee bit more money, but the gains are more than significant.)
4. Educate the public of their rights and their right to complain. Make grievance addressal a fast-track forum.
5. Have a working monitoring mechanism with greater powers with local bodies and not merely some centralised body.

It would be important to note here that our cities reflect us. To a great degree, our cities are in the state they are because of how little importance we place on excesses like dust. The lesser we complain, the less we take steps to demand basic health standards, the more dust is going to get kicked up.

How green are cement, steel and bricks ?

I saw this query on an Internet group a while back and felt it was important to pen down my thoughts on this. I have been talking about this for a while now, but never got down to writing about it. So here goes.

Cement, steel and the standardised burnt clay brick

To arrive at a better understanding on how green these materials are, one would have to address this from different perspectives:

• From an embodied energy perspective
• From a scale of consumption perspective.
• From a regional impact perspective
• From a construction vs livelihood perspective

Embodied Energy

An IGH Projection

Cement and steel are processed materials, that consume a lot of energy in their making. Modern day Cement mainly is a mixture of various components, essentially lime, and other binders.
Cement from the time of the Romans, has been a binder material used for making building components adhere to another. Lime was an crucial part of this mix. Other pozzolanic materials like volcanic ash, etc were also added by other groups.  In pre-industrial times, the production of cement did not involve much more than animal driven and human labour.... from the extraction of raw materials right down to the production of the cementitious mix. Today of course, cement production involves the use of generated energy (driven by electricity, diesel, coal, etc)
Steel in construction is an industrial era contribution (barring a few earlier usages), and has become a mainstay in all forms of construction. In the 5000 plus years of civilisation history, it is interesting to see that a material that was never ever used in construction , has become an integral component of all construction in just over a 150 years (not that this bad in itself)..

A projection by IGH

Burnt Brick production has remained the same over the past many centuries, but the standardisation since the British times has seen an inefficiency in the burning process. In earlier times, bricks came in all sizes and shapes primarily due to the differences in clay compositions between regions, resulted in better burning. Today, the standard burnt clay brick is 9" x 4.5" x 3", all over the country.

A great amount of energy goes into the manufacture of modern day cement, bricks and steel .There is a dearth of consistent data on the applicable embodied energy for these materials, primarily due to the varying conditions of production, sources of energy and scales of operations. However, if one does consider the potential contribution to CO2 emissions by these materials used today, the significance is apparent. On average a 1000 sft residential unit (independent house or apartment) would result in the emission of anywhere between 45 to 72 MT of CO2 into our atmosphere. In the context of over a 100 1-million plus population cities in India alone, and with an ever burgeoning urban population this is significant.

Consumption

A file picture of iron ore mining activity in Bellary, Karnataka.
Photo: M. Ahiraj, The Hindu

What is even more significant is the rate of production of these materials in the last 100 years (post the industrial revolution). The modern global economy has created a mad rush to urbanise and has pushed rural populations to cities in search of greener pastures. The combined effect of Business, Growth and Migration has led to a boom in construction activity for business, residences and infrastructure to support this. The rate of consumption is fed by a hitherto unseen rate of extraction of raw materials and production of construction materials and components.
This consumption has great side effects. Beyond the CO2 emissions, up-the-chain environmental damage due to pollution, afforestation, and harm to ground water is grave and has resulted in changing the surface of our planet like never before. Transport of these materials has meant the creation of further construction corridors and which has led to massive atmospheric pollution due to petroleum exhaust (incidentally, never before has petroleum been burnt in such a scale as in this period). The large scale construction activities that we see in our cities and towns today create dust and air-pollution, causing health hazards like never before.

Regional impacts
Change is inevitable, but it is the nature of change that has to be examined. There has been tremendous and rapid transformation in the way we build, originally from a construction material/system point and eventually in the forms that the architecture has taken. This change is more of an imposed change, fuelled by industry set up in independent India and also by the great aspirations of the Indian masses. Agendas set by early politicians and subsequent governments further added to the modernisation of India. This trickled down to built form, but has resulted in a complete alienation (and extinction in many cases) of building traditions and regional architecture. Cement, steel and the modern day brick rode this wave of change. RCC, cement and 'sariya' (reinforcement steel) are now household words, and almost every contractor and mason knows how to work with these materials (at least has a working knowledge). These materials are now unshakeable and integral components of construction in urban India. They are considered as the solution to all evils of what is perceived of as 'kucha' works. So deep is the knowledge loss that current day construction workers hesitate (and refuse) to apply traditional materials and systems that were prevalent only half a century ago..

Construction labour at a site

A disappointing outcome of the latter half of the 20th century in India is the emergence of a monoculture in architectural form that has taken over its urbanity. While nationhood united diverse people and cultures, the direction construction has taken ever since is leading to the wiping out of this very essence of diversity. What is more ironic is that numerous studies done over the past couple of decades have shown the limitations and inability of this architecture/built form in providing appropriate occupant thermal comfort, colour and character, and so on. Yet we persist. While change that is inherent (or from within) is understandable, un-reined change with no care for the consequences is not.

Construction vs livelihood
Resources followed the money. Skill-sets needed for RCC construction were simple and were honed, whereas traditional building know-how became unviable over the years. Industry supplied cement, steel and the standardised burnt-clay brick to every nook of this country, while traditional skills were limited to small regional (maybe even sub-regional) extents. Therefore, a moving populace (mostly rural folk looking for better incomes) picked up what would earn them an income irrespective of where they locate to, and moreover there was a lot of jobs for the picking. This scenario is still unfolding, killing our building traditions steadily.

We see that this illustrious group of modern day materials (cement, steel and the standardised burnt brick) has a high embodied energy, cause immense environmental damage (both up and downstream), has altered the regional diversity of our building traditions and systems, and is continuing to wipe out the livelihoods of traditional crafts persons. The 'Business As Usual' scenario of modern day construction materials and systems  is unsustainable and needs an overhaul. Alternatives to these materials and construction systems are urgently necessary in the context of the ecological tilts that such human activity has caused over the last century and a half. Small gestures of reducing a bit of this or that is not going to add up as anything significant. The time for a complete re-think to redeem ourselves is now. 

Why does sustainable building make sense to a developer?

One can't be blamed by reacting like this...."What? Developers going green?? Not a chance!". Unfortunately, the general reputation of  the developer lot is to blame for this.
The proposition of developers going sustainable does seem a bit of a stretch, what with the soaring prices of land, and with a volatile market putting a pressure on sales. One tends to believe that developers would not risk sales to attain even a tinge of green. or, let alone going the sustainable way..
Before I launch any further on this let us look (once again) at Sustainability. Sustainability is about defining the thresholds within which if one acts the ability of future generations to live life as we do, does not get compromised in anyway. Sustainability is about responsible consumption and becomes important as we consume more and more as a population. Buildings consume a lot of resources in their making, while contributing to about 39% of the worlds GHG emissions (Source: U.S. Department of Energy (DOE), 2008 Buildings Energy Data Book.), and therefore it is imperative that they are built responsibly.
Sustainability is also about being resource efficient, and that any developer gets.We have no option but to be responsible for our actions and the environment. Great strides are being made in areas of pollution free technologies and energy consumption in buildings. While there is minimal focus on the building systems, this accounts for the majority of the CO2 emissions during the entire lifecycle of the building. This is bound to be the next focus. Self-sustaining habitats that strive towards occupying a zero ecological footprint are the future.

So, why do developers need to change the way they build? Let us try and populate a list.

• Sustainable development ensures that business secure their long term success through triple bottom line practices which address the environment, social needs and business growth 
• The world is rapidly rising to the need for sustainable green practices in all spheres of activity from businesses to transportation to construction. 
• Sensible and sustainable design and construction are the emerging paradigms and it is desirable for developers to lead the way and be at the head of such a transition. 
• Sustainable construction enables a developer to broaden their scope of building materials and systems. All this at comparable and sometimes lower costs than the conventional
• By adopting sustainable building methodologies, a developer insulates himself to a great degree from the vagaries of the marketplace. Since materials and skills are inherently local, global turmoil would not have an adverse impact on development works.

Another way of addressing the choice of going sustainable is to look at the impacts of 'Business as Usual', as captured in the left half of the graphic above. The graphic on the right shows the balance of environment and social aspects along with business interests, which is a more comprehensive model. Unsustainable development burdens resources, the business and makes for stressed lifestyles down the line. A sustainable model on the other had adopts a policy of 'making do with as little as possible', without impacting it's survival into the future. On the bright side, there exists within most professional and seasoned developer groups a keen sense that in satisfying the needs of the customer lies repeat investments, recommendations and so on. I believe in this we already have the foundations for transforming into a sustainable business. 

What impact does Sustainability have on the developer's brand?

• It will earn the developer the status of a green organisation, a must going into the future. 
• Communicates to the market the environmental responsibilities of the developer.
• Assures the market that the product has been designed with them in mind… in terms of environmental health, family health, etc 
• Carries the message that the development would secure the users more water, would consume lesser power, and would also pollute the environment less

In employing environmentally sensitive and sustainable design/building technologies, one is actually securing the future of the customer. The reality of a sustainable approach is that one is also addressing health and lifestyle aspects of the customer today. By adopting a sustainable mandate one is addressing the client base's running costs, access to essential resources, internal living health and also providing a rich built environment for overall development.Securing the future of the customer (which means you also address their environment) means that you secure your business' longevity.

So developer, what are you waiting for?

Green Homes to remind you of the 'Old Bangalore'

Bangalore, the garden city of recent yesteryears, has been transformed into a metropolis that attracts a quarter of a million people every year. The growth that was fuelled by the IT boom around Bangalore has become a scourge to living amongst convivial greens. The retirement paradise of remnant sahibs, the Anglos, military officers, and railway baboos has become a cluttered city of undefined character. The steady stream of movers into the city has put immense pressure on the city’s infrastructure and amenities like abundant water supply, clean air and the ‘sound of silence’ in the shade of 500 year old trees, is evanescent.

Image- skyscrapercity.com

Colonial and other terracotta clad bungalows have been torn down and replaced by apartment blocks and shopping malls. Land prices have escalated so much that people are happy to forsake their garden paradise for the sheen that bucks could add to their lifestyle. No consideration has been evinced for the resources of the city, or its past promise of languorous afternoons and walks down tree-lined boulevards. On the pretext of globalization, the city’s people have huddled themselves into a myriad of cubbyholes, all the while pining for Bangalore’s past resplendence as a retirement post among serene environs.
In the last few years, of course, the scenario is changing. Reports of receding glaciers, the thinning ozone layer and the human impact on global climatology, not to forget the CII IGBC promoted green building certification, have woken people out of their slumber of indifference and apathy. People are adopting ‘green’ practices, albeit a few only, almost as penitence for the sins committed against Mother Nature over the last few centuries. But penance alone will not bring about Grace; new ways of living have to be contemplated to make the planet a worthwhile commentator of our times to the next generation.

Bangalore developers who built with impunity are now trying to add a soft touch to their footprint. Eco-friendly housing, waste management, rainwater harvesting, recycling, energy conservation and indoor air quality are terms that are being bandied about as the new mantras to exorcising the past and ushering in an effulgent future for the residents. The denizens are becoming wiser and are demanding adherence to norms; are becoming active and questioning the reason behind every trend. One day, soon enough, the citizens will have realized that they don’t need to be cornered into a pigeon holed high-rise, or brook the shoddiness of a tardy developer.
Building or buying a green home, even if the plot sizes are relatively smaller, or a tad further out of town, makes eminent, and imminent, sense. Such a green home could bring home the essence of the old Bangalore (in spirit if not in form) while doing one’s bit to reduce our ecological footprint. While some of the green concepts are easy to comprehend and implement, there are many aspects which require professional expertise. Greening, besides requiring huge doses of common sense, draws its inspiration from science and technology, social systems and practices, local artisan-ship, heritage architectural concepts and designs, and more importantly, its intent is harnessed on a strong edifice of ethics, morality and prudence. There is an increase in the number of professionals and organizations who now offer consulting services on the elements of green construction and this could be well our chance to make a grab for retiring in serenity in the fractured bosom of Bangalore.

The value of embodied energy in this world of energy efficiency

The world of today seems to be caught in this frenzy of energy efficiency... ok maybe only that part of the world that is focussing on reducing our impacts on the environment. Rightly so. The dots have been connected from the spending of units of electricity or fuel from petroleum products and coal to the emission of Carbon Dioxide into the environment. Various figures are thrown around ranging from around 1 kwh of electricity leading to between 0.8 to 1.2 kg of CO2. Similarly, 1 litre of diesel or 1 kg of coal burnt leads to about 3.2 and 2.3 kg of CO2 emissions.
The significance of energy efficiency by reducing energy consumption in any form is significant. A residential building for example stands to reduce about 1 ton of CO2 emissions every year, by adopting specific energy efficiency measures. This example however, is for a home in Bangalore that uses air-conditioning moderately. The emission reduction by taking such steps can vary hugely in different categories of residences and is more significant in higher energy consuming built environments- commercial buildings, 24x7 office buildings, air conditioned complexes, hospitals and industry. But any savings is significant, specially if you extrapolate it across an entire city, or, nation.
But what about the making of the building itself? Any building activity today is supported by huge energy guzzling building materials and services industry, not to mention the transportation of materials. More products are today industrialised than ever before... Demand for more buildings fuels more such industry and therefore a greater consumption of natural resources with expenditure of huge amounts of energy in doing so. It is only fair to take into consideration all this energy, or, the proportionate share of that per square metre of building built as the energy of making that building. The embodied energy of a building therefore, is the sum of the total embodied energy of all parts of the building. This embodied energy calculated in Mega or Giga Joules or in kwh is converted to achieve the sum CO2 emissions in kg or tonnes.
There are a slew of embodied energy figures for various materials, and the list is not exhaustive... from an Indian perspective, but Institutes like IISc and IIT Roorkee are taking their shot at providing some baseline figures.
The savings calculations however are an entirely different deal. The current method is to compare the sum embodied energy of your building to that of a baseline.... which, in simple terms means a building that can be considered similar in size, scale, purpose and group that it caters to, but built using conventional, current and commonly used building materials and systems. However, the more efficient way, is to compare your savings (in terms of your design and layout) to the alternative materials and systems that you could have used in the very same building that is being assessed.
So how much can we save by reducing the embodied energy of a building? A substantial sum depending on the choice of building material, system and the management of construction. In one building that we built, we estimated about 20,000 tonnes of CO2 emissions saving for about 25,000 sq metres of construction....while in an another building the figure same figure fell to about 5,000 tonnes for a building of about 8000 square metres. Why the difference? Simple. One building adopted achieved greater reductions due to the kind of technologies adopted....building blocks, avoiding a basement, flooring choices, etc. The savings could have been more in the first building.... if we had adopted a more energy efficient alternative to the RCC slab... or, by finding better alternatives to the internal roads built.
A building takes anywhere from 8 months to about 36 months to build, depending mainly on size and scale, and therefore the time frame for these substantial emissions for the building process is also limited to that. Energy savings in operations on the other hand adds up over the lifetime of the usage of the building. Savings in embodied energy could range from about 0.5 to 1.0 tonne per square metre. In a residential building, the energy spent ranges from about 5 to upwards of 20 kwh per square metre per year depending on the income group and the level of air-conditioning. In 20 years, this translates to about 100 kg to 400 kg of CO2 emissions. In a commercial building, a savings of about 50kwh per annum per square metre would mean a CO2 emissions savings of about 80-100 kg. In about 20 years, that would mean about 2 tonnes of CO2 emissions saved.
Just by these above cases, it is clear that the impact of how we build is significant and that one cannot neglect the CO2 emissions savings due to choices made in the building process.

Lessons learnt for building design from the experience of driving

How many of us have had this experience? Park the car out in the sun and return after a couple of hours.... and we reel back due to the excessive heat within.

To counter this, we do two things:

• One, we park the car in the shade
• Two, we roll down a couple of windows of the car down a crack

In both cases, we have a great level of comfort that is achieved, at least when we compare this to the very first experience. Now let us look at both these changes to the situation closely.

The first instance, where the car was parked in the shade benefited due to the reduction of direct incident radiation. Nothing else changed, only the external environment was modified by introducing an obstruction to the direct sunlight.

The second instance, where the car was parked with the windows slightly down benefited due to the hotter air being vented out from the upper portions of the car, where this internal air is hottest. Nothing here was changed, only the body of the car was made to breathe.

Cut to how a building works for a bit. The body of the car can be compared to the building shell- the walls, the roof, the windows, etc. The windows of the car are akin to the openings on a building- windows, ventilators, clear storeys, etc. How the skin of the car works in affecting the internal thermal environment is comparable to that of the building shell.

If we consider how this shell works in keeping the car thermally comfortable, we find that in most instances it seems to fail, as in the example given above. The point that I am making is that the entire shell of the car (the insulation included) that was meant to manage the gain of heat (in hotter climates) and the subsequent loss of coolth (yes, it is a word in the HVAC industry)  from internal air-conditioning, was inadequate in doing so. I wonder (humour me for a bit), if we had designed cars with a secondary shade providing shell (forget the aerodynamics for a bit), perhaps with perforations (kind of like a jaali), which would perform like a self venting system of sorts, would we have reduced the insulation that the car would have ordinarily needed? Could such a cutting off of direct heat radiation also have lead to a reduced usage of air-conditioning?
Let us now apply the same logic to how a building is designed. Current practises take into consideration local climatic conditions and then design the building shell with materials (or composites) with the desired u-values to ensure an appropriate thermal flow balance. Like in the case of the car, this extra insulation of the building can be reduced by first starting with a modelling method that adopts aspects of shading and venting on a shell with conventional specs. In hotter climates (like most areas in the plains of India) where it is all about keeping the heat out, this would apply greatly.
A double shell  for instance could also be designed to provide extra strength.... a greater base level of air-exchanges would also ensure better internal air quality.... and eventually, a building so designed would end up spending less on air-conditioning costs.
Similarly, other thermal comfort influencers like humidity, can also be addressed by drawing on such parallels/inspiration. Ever wondered why when it is uncomfortably humid, and you are driving, you feel much better, by just rolling the windows down? The breeze helps remove the perspiration, and one starts feeling better. Now, in the building context, when it is humid, all one has to do, is to induce such an air movement. It is not necessary to jump straight to air-conditioning.
Many of us hasten to switch on the AC in the car and do so primarily because we cant stand the dust and pollution of our cities. A similar scenario of dust is played out in buildings, and somehow and air-conditioned environment is always seen as the universal solution. When all we needed was a dust screen! We know that plants perform that role and so do artificial louvres and 'jaalis'. Incorporating such measures would surely address dust control but don't you think that it could also add some vitality to otherwise banal façades?
So, what say we take one hard look at the experience of driving and how we deal with thermal comfort...again?

Is a green building meant to look any different?

I am tempted to say yes.... mainly due to what today's buildings have begun to look like.
I have a suspicion that buildings would end up taking a different form and have a different appearance if they are built sustainably. The variations would be starker between different regions. Today, we build in pretty much the same fashion anywhere in our country. In fact, we have already started claiming that our buildings speak a global language and rightly so. Most building technologies are floating across geographies and creating what is now the new global expression. Creative ideas are encouraged more than refreshing regional ideas.
Why would these green buildings look different? Let us look at how we built 100 to 200 years ago. Those buildings could be called 'deep green' buildings. They took absolutely no power to make, they were almost entirely built out of materials and skills sourced from within a 100 km radius, they were made thermally comfortable, they did not consume much energy to run (primarily for a few oil lamps and biomass stoves), they had the lowest LPDs, they were dependent on sustainable water sources and managed what little waste they generated in what some would call green systems (read dry toilets, leach pits, etc).
With no global dictat or influencers, these built environments reflected strong regional attributes and it would take no time for a person who would wake up in such environments to figure out where he was. We can’t say the same about today's built spaces.
We have two choices. One, we could adopt core green principles for our built environments and I would suspect that we would end up infusing those characteristic regional attributes of the day. The principal driver here would be to occupy a minimal ecological footprint and ensure broad reaching sustainability by addressing issues of livelihoods, traditions, skill-sets, managed change, etc.
Two, we could be guided by notions of our current global expression, and work incrementally on reducing all resources related to the built environment. Here, the concern is that it would become purely a number crunching exercise... lesser change to soil, lesser waste, lower energy, etc. Today we have cement plants in accessible distance (a relaxed, looser radius thanks to current Green Building Codes), but does all the raw material for making the cement come from the same region? Steel comes from a plant within a similar acceptable distance, but what about the resource that it needs to run? The coal, the power, the iron ore, etc.
Glass can be made to have a greater green quotient, through greater recycled content, and can be made more insulative, but what about the energy that goes into the making of such glass?
This second option makes me wonder if by our current building choices we create resource guzzlers (unsustainable buildings) and then venture out to make those very components efficient? What if we chose not to use that much glass, or that much aluminum panels with insulation? Could there be a rethink of what sustainably built buildings could look like?