We all know that the LEED system can be gamed but that it could be turned so completely on its head was news to me.
The Bank of America building at One, Bryant Park, New York has a LEED Platinum rating and was the first skyscraper to ever be awarded this but now, it turns out, it uses more energy per square foot than other building of similar size in all of Manhattan. Wow.
It was hailed as a major achievement by none other than Al Gore who set up his offices there. The basic problem is that LEED is largely based on computerised energy models and “intent”. This makes it open to abuse because it’s easy to purportedly intend something at the design stage and then change the goalposts later on.
Coincidentally, just this morning, I was speaking to a couple of marketing guys who were trying to convince me to attend a “green summit” next month and one of their selling points was LEED. I declined, telling them exactly what I thought of LEED but I wish I’d seen this article just a few hours earlier:
In hot climates, the overall energy usage rises as you increase the glazed area. Curtain walls, therefore, are highly inappropriate.
I have ranted about glass façades for a long time and this editorial by Sunita Narain of DTE has inspired me to add a couple of paragraphs to the original one. Among other things, she has written about a recent study by IIT-Delhi which found that, in our hot climate, the manufacturers’ claims of special coated glass or double/triple glazing being able to reduce heat gain are rather hollow.
One of the other specious arguments put forth in an attempt to portray glass curtain walls as green systems is to say that it reduces the electricity consumed for lighting. This is a half-truth. Leave aside the uncomfortable glare that people working inside such buildings have to put up with, let us make a simple comparison.
Consider a 10m² conventionally designed space. Assuming that we don’t take passive cooling techniques into account, the air-conditioning load will be in the region of 3,500W (1 ton). Lighting the same space, on the other hand, will need just 50W with fluorescents or 40W if we’re using LED fittings.
Now, imagine a similar sized curtain-walled space. The maximum saving that can be achieved by reducing lighting is a puny 50W. However–and this is the big problem–air-conditioning requirements will probably have risen to a whopping 5,000W. Even with all the specially coated and multi-layered of glass in the world, the total requirement is unlikely to be anything less than 4,500W.
So yes, we may not use as much electricity for lighting but, I’m afraid, the energy usage for cooling will go right through the roof and no amount of marketing spin can get around this simple fact.
Just in case I’ve got you visualising rodents scurrying about where they’re not wanted, ease your mind; the rat trap bond I’m talking about is simply a method of laying bricks when building a wall. It’s similar to the common “Flemish” bond but instead of putting the bricks on their face, they are placed on their edges. This leads to cost savings because less bricks and cement are needed which, in turn, reduces the embodied energy of the wall.
Bricks are laid on edge to create an air gap between two layers
Laurie Baker took every opportunity to try and make people realise the value of this method but, by and large, the 20-25% saving in brick doesn’t seem to have been appealing enough. The rat trap method of construction was popular in England until the start of the 20th century but sustained lobbying by the brick-making industry convinced people that that it was not strong enough to build load-bearing walls.
That is rubbish of course; it’s strong enough for one and two storey buildings as has been proven over and over again by Laurie Baker’s lasting work. But masons too are not usually happy about adopting this system and come up with all sorts of excuses to try and avoid it. I have to admit that, till date, I have not pushed hard enough against their inertia but now I’ve just got one more reason to do so.
For the ShKo bungalow at Karjat, I plan to use the rat trap walls and wanted to know just how much difference they would make thermally. Nobody seems to have done a calculation of the difference — at least there was none that I could find. So, armed with some data from thermal calc and the energy evaluation component of ArchiCAD, I tried to do just that.
Taking just a simple 3m x 3m structure with no openings, I ran a calculation for both types of wall. Result: average U-value of the structure’s outer shell dropped about 15% compared to conventional walls and the energy required for cooling also fell by about 8%. The difference was exaggerated because the model had good roof overhangs to shade the walls.
Still, when you think about it, 8% is nothing to scoff at. In addition, the embodied energy is reduced quite dramatically and, of course, Laurie Baker’s original reason for using the rat-trap bond still stands — the wall is simply cheaper to build.
Now, I just have to go and steam-roll the masons into learning a new technique.
This Wall Street Journal article on the collaboration between reclusive Swiss architect Peter Zumthor and ascetic Dutch landscaper Piet Oudolf made me think about my own (much less famous) interaction with A.Y. Retiwalla for the Karjat Resort a decade ago. Unlike the collaborators here, neither of us had heard of the other before and were brought together by the client, Dr. Beramji. Still, the mutual respect and acceptance of ideas was similar and it ultimately led to something that was appreciated by all.
The restaurant, shortly after construction
The restaurant about five years later
No egos were bruised during our meetings — they were left outside
Mr. Retiwalla was already well established in his line and it is to his credit that he discussed things with a relative youngster like myself, purely on merit. Ideas flowed freely between us and, with Dr. Beramji taking a keen interest in every aspect of the project, the tripartite meetings were very enjoyable.
As Queen’s 1980s song, Radio Ga Ga, laments, “we hardly need to use our ears“. Actually, we abuse our ears or, at the very least, ignore the abuse that others heap upon them.
Unfortunately, while we are easily able to close our eyes, nature hasn’t equipped us with lids to effectively shut our ears.
But what does architecture and design have to do with all this?
Usually, unless an architect is designing something with an overt acoustic requirement like, say, an auditorium or a recording studio, only visual aesthetics are considered. However, as Julian Treasure points out in this TED talk, the auditory aspect is more crucial than we realise.
He illustrates just how detrimental the effects of noise can be, not only in special environments like hospitals or schools, but in homes and offices as well. For myself–even though I’m quite aware of the debilitating effects of loud noise–the talk was quite an eye-opener.
For the MChi interior site in Bombay (Mumbai), I found some really nice LED light fittings but they are more than three times the cost of identical CFL fittings. Now we all know that LEDs consume very little electricity and they have an extremely long life but I wanted hard numbers to convince my clients – after all, they are the ones paying for everything.
It didn’t take long… At the light shop, it was pretty obvious that the 18W LED fitting threw as much light as an identical one housing 36W of CFLs. Frankly I was a little surprised by the 1:2 power consumption ratio because I always assumed it was more like 2:3. However, LED technology is making such rapid strides that yesterday’s facts are already redundant. Putting all the costs into a spreadsheet immediately produced a very compelling argument in favour of the former.
An Example of Total Cost of Ownership – LED v/s CFL
While the life of an LED bulb is in the region of 50,000 hours, the calculation over such a long period (while in favour of LEDs) is rather unfair because even at 5 hours per day, that means 27 years. Instead, I’m working with 30,000 hours which represents a more realistic 16 years.
Even accounting for the fact that the LED driver (an electronic device that regulates the power that LEDs receive) doesn’t have a 50,000 hour life, the calculation still showed a huge saving.
The calculations here are not likely to remain valid for long because the cost of power is sure to rise even further and that of LEDs can only go downwards.
Last week ended with a site visit to Nasrapur, Karjat. This is the fourth design in the same general location after the [RaBV], [BAli] and [LGEs] bungalows so I’m extremely familiar with the area and climate. Part of this particular one-acre plot is prone to flooding during the monsoon, and the only portion that is safely outside the flood zone (even considering the massive downpour of 26th July 2005) is on a mound near the road. On this rise stands the ruin of an old shed which I had seen earlier but was unable to explore properly because, until recently, it was overgrown with Mucuna pruriens — locally known as khaj khujri. This climbing shrub causes extreme itching on contact with young foliage or seed pods and I wasn’t about to take my chances.
View from the river side towards the mound where we will build the ShKo Bungalow
Unlike other plots in this cooperative society, this particular site doesn’t have too many mango trees — mostly due to the flooding aspect. We intend to plant native trees such as Millettia pinnata or karanj which thrive in such conditions.
I am really looking forward to starting the design. Conceptually, I’m looking at a string of structures — some of them without walls — forming a sort of “C” shape around a water body. The river, unfortunately, is too far away and not visible from the mound. The mountains of Matheran and the Garbat plateau, though, give a splendid view to the West.
For most projects, I not only design, but also execute the work. For this one, though, because of distance, I only did the former.
The clients, manufacturers of packaging material in Cuttack, Orissa, wanted to construct a factory that was not just functional but, to the greatest extent possible, a green building in all respects. The product they make is hardly environmentally friendly, so it was somewhat ironic, but they had a genuine desire to make a change for the better so I agreed to take the assignment.
Design Principles
The initial conceptual structure had clerestory windows on the north and curved roofs to take maximum advantage of prevailing winds
Initially, the structure was to be of a single story only so, had that remained the case, the factory might just have looked like a variation on a theme with north-light roof trusses and curved metal roofs instead of straight ones.
Instead, and as luck would have it, the clients decided that they needed at least one additional floor to house the lighter machinery. Land in this area–alongside the Mahanadi river–is expensive and it would do them no good to scatter multiple structures all over the 2 acre plot. That posed a problem for the design as the clerestory windows would be of no use to the lower floor — either for light or ventilation.
North West corner of the factory. This was the final design based on which the factory was actually built. You will notice that windows facing North are twice as large as those pointing West.
So, to allow for the clerestory windows to be used by both floors, I thought to turn them sideways. Back at the drawing board, I realised that only allowing windows on the North and East would mean the interiors of the factory would be dark for much of the day — not to mention that natural ventilation would be nil. On the other hand, too much light from the South or West was not desirable and neither was a draft that could carry in dust particles.
So I reverted to an undulating form–a double wave form in fact–that not only softens the factory outline but also works better for ventilation. Here the smaller waves face the South and West and the bigger ones face the North and East.
A rendering of the factory interior shows how the light enters indirectly
Now, when light enters, it reflects off the inner side of the baffle walls. Any heat that is generated remains in the immediate vicinity of the windows. Additionally, the upper of the two windows is bottom-hung to allow hot air to easily escape.
Between successive waves in the baffle walls, horizontal awnings protect the more conventional windows from the sun during the hottest times of the day. In fact, sun-studies were carried out to ensure that the sun’s rays almost never directly reach the building’s interiors between 10:00am & 3:00pm.
Materials
A view of the factory under construction shows the flyash bricks used for the walls.
Being a large structure which needs to take heavy loading, the framework and slabs had necessarily to be in RCC — a material that I avoid using when it is not required.
All the walls, including those of the baffles were from flyash brick and plastered only where necessary. Initially, we wanted to use the local laterite but that worked out much too expensive.
There are a number of things you can do to attract butterflies and birds to your garden. Here is a basic list that may be useful as a starting point for people living in peninsular India. Please remember that this list is neither complete nor comprehensive because habitats vary so dramatically across our country. I’ve tried as far as possible to list local species but some, like the Lantana, have naturalised in our country and have therefore found a mention.
Grasses
A number of butterfly species lay their eggs on grasses – but not of the cultivated kind. Unless you have a very large plot, it is unlikely you’d want to allow these to grow. However, if the possibility exists, it is nice to let a patch of garden in a corner somewhere actually grow wild.
Bamboos are food for some butterfly species and refuge for many birds and other creatures. Keep them a little distant from your house if you’re petrified of snakes, though.
Even if you live in the heart of a city like Mumbai, you will be surprised by the variety of birds you can see if there is enough greenery around. I’ve seen the beautiful Paradise Flycatcher in Breach Candy which is, barring a couple of tiny green pockets, as concrete a jungle as you can get.
Although the links above all point to wikipedia, a very good resource I have found for Indian plants is Flowers of India. The site aims at having comprehensive information about Indian flowering plants with their common names (especially in Indian languages), pictures and details of habitat and distribution.
Erosion of soil is a very real problem that can crop up when we encounter sloping land on a site. In this article, I’ll outline the measures taken on two different sites where erosion needed to be controlled. The first was done entirely via plantation and the second (where the foundation of a building had to be supported) involved terracing of the land — in conjunction with plantation of course.
Slope Stabilisation with Vetiver
In the year 2003, a client of mine wanted to buy an 11 acre plot of land along the Narmada river. It was a lovely location but the soil was very soft and powdery and the land was scarred by deep fissures where rainwater flowed down to the main river. What made it downright dangerous was that these steep gullies were collapsing at points and something needed to be done before parts of the plot got cut off and became inaccessible.
At the time, I suggested reducing the angle of the slopes and planting local reeds that grew along the riverfront to hold the soil. The first part worked but the second did not. The wild plants refused to grow where we wanted them to and something else needed to be found. That’s when she decided to try growing Chrysopogon zizanioides — Vetiver (also called Khus).
What happened next was almost miraculous. The Vetiver took hold of the soil and bound it in a way that not only stopped erosion but allowed rainwater to seep into the soil instead of letting it all run off to the river. As a result, even the trees growing in the gullies got healthier and what looked like an almost barren landscape then, is now a great example of how working with mother nature is far more productive than trying to fight her. And plantation costs a fraction of what it would if we used “man-made” solutions.
What makes Vetiver different from other grasses is the fact that it’s roots do not form a horizontal mat like the others but grow downwards as far as 4m (13 feet). Another good thing is that it propagates in a way that makes it easy to control – so it doesn’t become an invasive weed.
To know more about Vetiver and how to use it for erosion control, go to the Vetiver International Network Website and download their manuals, videos and presentations.
Terracing the Land
Now, while I’ve been extolling the benefits of natural solutions, there are times when we simply have to use brick and mortar solutions when structural demands have to be met. The [RaBV] bungalow at Nasrapur was built on steeply sloping land and we not only had to prevent erosion but also make sure that the building’s foundations had rock solid support even if an earthquake struck. In such a situation, simply planting Vetiver, or any other vegetation for that matter, would never have been sufficient.
The first thing to do in the design was to follow the slope of the land as closely as possible. The main floor level was split with the living room sunk by about 0.6m (2 feet) from the rest of the house. Then, the verandah which projected by 2.4m (8 feet) beyond the house line was almost 1.8m (6 feet) above surrounding ground level so instead of filling it up, a little earth was excavated and an extra level – like a basement – was created below the verandah. Not only did this reduce loading on the peripheral foundation wall in a big way but is also served as a space for garden implements, a separate room for rainwater harvesting tanks and parking for a motorcycle.
The verandah effectively then, became the first terrace. Then, to buttress the foundation, a second terrace was created just in front of the basement. Here, we planted only shrubs and bushes – nothing with strong roots that might weaken the stone wall at some future date. Finally, we built a retaining wall to support the second terrace.
Maybe it was unnecessary to go so far but, when there is going to be no second chance to correct a mistake, you tend to err on the side of caution. Around the bungalow, on non-critical slopes, local vegetation has been allowed to grow naturally and has taken root well enough to protect against erosion.
The Bank of America building at One, Bryant Park, New York has a LEED Platinum rating and was the first skyscraper to ever be awarded this but now, it turns out, it uses more energy per square foot than other building of similar size in all of Manhattan. Wow.
