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?

Tenets of Sustainable Living

Perhaps we need a sustainability version !!

If we had to define what would constitute the basic principles when it comes to reducing your ecological footprint what would they be?. Here is one version:

• Consume less
• Power
• Water
• Building/construction materials- go simple tech as against high-tech
• Consumer goods
• Consume local
• Eat local produce
• Build using local materials and skills
• Generate less waste.... Re-use and recycle
• Build using old or discarded materials... apply clean tech
• Compost and share with neighbours
• Choose what you buy.... things that wont contribute to the waste you produce
• Throw away less
• Occupy less space
• Do you really need all that extra built area?
• Do you really need that big a car?
• Go independent... as far as possible
• Build as much with what you have
• Be self sufficient in your harvesting water and generation of energy (as long as it makes sense in terms of the Life-cycle)
• Manage what little waste that you generate
• Travel less and travel green
• Use your car/two-wheeler less frequently
• Use a bus instead of your car/bike.
• Use a cycle for the short distances
• And if you can walk... go for it.
• Work as a community
• Share resources
• Share travel resources
• Assist in solving each other's problems
• Get others to live sustainability, it is your responsibility too
• Give back
• Recharge the ground water
• Share power that you generate
• Plant as many trees as you possibly can
• Take only what you need... probably the most important since it is this very appetite that has gotten us into this environmental glut

We could have been the 'People of the tanks'

I guess most of us will be saying, "what is he talking about?" But, that is just it. Bangalore is set in a landscape of a 100 tanks (for a lovely insight read the book "Deccan Traverses'), has had a history that recorded for over 400 years.

Many of us know of the lakes around Bangalore, but that is part of the change brought in by the limited understanding of our administrators and planners. The system stretches from beyond the Northern boundaries of our city limits and goes beyond the point where Cauvery plummets many levels at Sangam, making all of us in the lands of Ramnagaram, Maddur, Mandya and Srirangapatnam inhabitants of this landscape. Even more significant is the fact that this fabric of tanks is a result of human actions. Yes, all of this is man-made! The will of the people made this landscape and it is the lack of it that is fast erasing it.
So why 'tank people'? Well, it formed the very life fabric that sustained this slice of civilisation. Each village/ hamlet had a tank of its own or shared a large one. These tanks would fill up during the monsoons and drained out water through a system of overflow valleys. The tanks would loose their water through the dry months, some completely and would leave large amounts of silt behind (a result of sedimentation). This silt formed crucial building material, for mud mortar/plaster and even for earthern walls, and was also used for agriculture as a nutrient rich soil. Most importantly, these tanks would help in recharging the ground water table. Potentially, these tanks can help in sustainably recharging rainwater for over twice the current population!! The landscape would change with the cycle of seasons, the tanks filling up during the monsoons and transforming into silted depressions for the drier months. This was the same space that we now occupy.
So where is this land that our city is in today?
The death knell was sounded by some interventions during the colonial rule... the closure of tanks, the conversion of drain valleys into narrow nallahs... stone lined channelways. Then came the babus and state government planners (post independence) who did more damage in the last 60 years than in the 200 plus years that the British occupied this land. Closure of tanks, treating them as lakes (completely misunderstanding their purpose and characteristics), and reducing this system to a pale reminder of the past.
So what is different?
The most significant change is that of identity and association. The link between tank and habitation has been forgotten. We no longer see them as great catchments of precious rainwater runoff. The nallahs, once percolating drain valleys, have been concreted and thinned clogging the system, or, encroached upon... causing great damage to both life and property every time we have even a good shower. The change in attitude is very visible in the health of these nallahs and tanks. They stink, sewage flows illegally into these systems in innumerable points. Many tanks have also been converted into permanent water bodies.. with stone masonry walls and pretty landscaped gardens to 'beautify' them. Probably the greatest change was the import of water to feed this city's population (executed during British times) from over 100 kms away near Mysore and therefore pumped up to over 900 feet! .... something that was never done for centuries before. Arguably, the population has also increased multifold over the last 100 years, but how do we explain that we had a water management system that could cater to twice the current population? This turning of our backs on a constant sustainable rainwater collection and recharge system combined with a callous and greed driven boring of our aquifers has resulted in falling groundwater levels.
This has changed the very way we live... our water comes from an unseen source (almost magical) so we dont see the link between these tanks around us and the water in our taps. The governments constant crowd pleasing statements of increasing supply 'to' the city has always conveyed the message that the solution for our water woes lies outside this system. This complete faith in long piped systems is also reflected in the city's wet waste treatment plants, large systems that are supposed to handle and treat the sewage from large quadrants of the city. This has also had an impact on the water equation of our city. Nearly all the water consumed by the city's inhabitants is drained out (inefficiently) only to be treated and led away from the city. In the original system, all waste water would find its way into the ground, filtered through rear yard broad leafed high-capillary plants and through the various layers of the earth.
Just take a look at that. Water was captured right around where people lived, allowed to filter into the ground, drawn out through open wells... and was recycled after consumption through a biological treatment system, again within the habitation limits. (of course, people did not waste great volumes of water in flushing)
This is what we today call a sustainable water loop. There is still hope, i think. The steps are obvious.