Sustainable ArchitectureProf. Avlokita AgrawalDepartment of Architecture and PlanningIndian Institute of Technology, RoorkeeLecture – 12Flavours of Sustainable ArchitectureGood morning. Welcome back to this lecture of online course on SustainableArchitecture. I am your course instructor Dr Alvokita Agrawal, Assistant Professor atDepartment of Architecture and Planning IIT, Roorkee. So, we have been discussing thecharacteristics and different aspects of sustainable architecture. We have looked at thesocio-economic aspects so far and we also have huge environmental aspects.(Refer Slide Time: 00:56)Now, environmental aspects are also the most tangible aspects as compared to socialaspects. For example, identity of a place it is not a very tangible aspect. Though weunderstand it, we easily apprehend ited, but yet it is difficult to put in tangible formswhile most of the environmental aspects are very tangible. All these environmentalaspects can be clubbed in bins of the five basic elements of nature which are earth, air,water, fire which I say energy and space.So, all these five elements are the elements which directly govern the environmentalaspects of buildings. For example, when we are talking about the earth we are talkingabout site, soil, vegetation, materials, construction waste and the waste which is produced from the buildings while they are occupied. So, all these come within the earthelement of the environmental aspect. NextNext, we have air; here we discuss about theair quality, the indoor environment quality in the buildings we talk about air pollutionand the toxic compounds which are emitted into the air. All of that comes under thedomain of air with an environmental aspect.The next and one of the most important ones is water. So, we have quality as well asquantity of water discussed here and the wastewater which is produced and treated. So,all of that comes under water. And, ina fire we talk about energy consumption and alsoenergy generation for example, renewable sources of energy will be discussed here. And,in space we talk about say daylight in buildings. So, all of that all of these aspects arevery tangible, they can be quantified, they can be calculated and hence an assessment canbe made.Now, so farfar, I have been talking about sustainable architecture. However, when welook aroundaround, we often look at buildings which are not called as sustainablearchitecture, but there are many interrelated concepts, for example; green buildings.Now, green buildings is a very common terminology which almost everybody is using.They are often synonymous, but there are slight difference, but there are differencesbetween the each of these terminologies and sustainable architecture though thefundamentals remain the same.(Refer Slide Time: 03:53) So, green buildings as per USEPA these are or this is the practice of creating structuresand using processes that are environmentally responsible and resource-efficientthroughout a building’s life-cycle from siting to design, construction, operation,maintenance, renovation and deconstruction at the end of the life of building.So, here green buildings mainly focus on the environmental dimension of sustainabilityand the other dimensions which is the social dimension specially takes a little backseat. Iam not saying this is not being addressed at all, but there is a greater focus on theenvironmental aspects when we talk about green buildings. The next is climateresponsive buildings. Now, these buildings respond to climatic constraints through theirdesign and construction.However, the aim of these buildings is to only respond climatically. Fortunately, many ofthe climate responsive buildings traditionally qualify to be called as sustainable buildingsbecause they do not they not only respond to climatic conditions, but while doing so,they use the best of materials, they use the best of the available resources and also theones which are renewable which are easily renewed in the nature.However, the main aim of these buildings is to respond to the climate of the place. Nextone is ecological buildings, now these buildings are structures that are designed to createand sustain mutually beneficial relationships with all of the elements of its local ecology.So, the buildings local ecology or environment is made up of particular physical andbiological elements and their interactions. (Refer Slide Time: 06:07)Now, these definitions will be more clear when we look at these examples. For example,for a climate responsive building Hawa Mahal is an apt example an appropriate example.Now, Hawa Mahal though it is resource intensive because it uses stone extensively, but itcreates absolutely comfortable environment indoors because it responds to the climate.So, that is what the main aim of the building was – to create climate responsive andthermallyly comfortable a comfortable environment indoors. So, this is climateresponsive building.(Refer Slide Time: 06:52) While this one is actually an ecological building now, it this entire building this entiresetup merges with the surroundings. It consumes the materials which are mostconveniently available locally and they use it in a manner that it does not affect theecology around these buildings and such buildings only enhance the ecology around. So,they do not disturb the ecology around them.(Refer Slide Time: 07:27)The most popular concept is that of a green building. It is a building which uses lesswater, optimizes energy efficiency, conserves natural resources, generates less waste andprovides healthier spaces for its occupants as compared to a conventional building. Now,out of all the concepts which are related to sustainable architecture green buildingconcept has become very popular for few reasons. And one of the most important reasonis that green building rating systems have come into place and because of these ratingsystems we can assess the performance of our buildings. We know where the buildingstands.So, there is a benchmark there are comparisons between building to building and weknow what performs and what does not. In this way people can monitor theirperformance vis-à-vis with others and get motivated. This has actually driven the market.Because of these rating systems green buildings are the most popular concept insustainable architecture as a larger domain. (Refer Slide Time: 08:49)So, we hear about green buildings and the rating systems almost every day. Thefundamental reason I will repeat again is the measurement which is possible throughthese assessment tools.(Refer Slide Time: 09:02)So, when we look at green buildings the broad categories of these parameters which areparameters of assessmentassessment, they are sustainable sites, water efficiency, energyand atmosphere, materials and resources, indoor environmental quality, awareness andeducation and innovation and design with location and linkages. So, these parameters in different rating systems are being given different weightages. So,in some of the rating systems these vary from country to country. So, in some of therating systems energy and atmosphere is the most weighted one. However, in someothers the material and resources or sustainable sites are the most important ones and likethat. In some cases awareness and education is totally absent and so on. So, thesedifferent parameters of assessment are present in different rating systems in differentweightages.(Refer Slide Time: 10:11)So, there are many- many rating systems in the world which are there, for example,BREEAM which was the oldest one to lead; we have GRIHA which is our own Indianone; we have Green Star; we have Living Building Challenge and CASBEE from Japanand a lot of these. We go to each one of these rating systems if we compare each one ofthesethese, we find a lot of similarities in the approach and the basic approach being thatof measurement and verification and through this measurement we are able tobenchmark the performance.Now, green or sustainable is often used interchangeably and we have already discussedabout the characteristics. (Refer Slide Time: 10:53)Now, if we are looking largely at the environmental characteristicscharacteristics, welook at the efficient management of energy and water and also material resources. So,efficient use and management of resources; we look at restoration protection ofenvironmental quality and the health and indoor environment quality.We look at a reinforcement of natural systems and we are always looking at the lifecycleof the building not just in a part of a phase of life of the building and we are looking atintegration of the design decision making process.(Refer Slide Time: 11:36) If you look at the benefits of green building so, it is not just because the entire greenbuilding rating program measures, monitors and verifies the performance of building,green buildings come with a lot of benefits. There are individual benefits, there areregional benefits and there are global benefits. At the individual level it reduces the billsfor energy and water, it improves the air quality and it reduces the maintenance which isrequired.At regional level we are talking about the system such as water systems, groundwaterrecharge, we are looking at vegetation, we are looking at ecology, we are looking atwaste management. At global level we are looking at benefits like global warming,getting away from global warming, climate change; we are looking at the forestprotection and all these.(Refer Slide Time: 12:37)So, green buildings come with a lot of environmental, economic and social benefitsthrough the characteristics and also the aims which we have set for green buildings. (Refer Slide Time: 12:55)So, the green building in general reduces energy use by at least 24 and it may go as highas 50 percent that of course, depends upon how the buildings are being designed, butfrom a conventional building this is what we are able to achieve the carbon dioxideemissions are reduced by a third. The water use water consumption at times reduces toaround 50 percent of the conventional one and the solid waste through the process ofconstruction and afterwards is significantly reduced at times to 70 percent.(Refer Slide Time: 13:32)Owing to these benefits the green buildings become a hugely popular concept. (Refer Slide Time: 13:38)However, if we look at what sustainable building versus a green building isis, we oftenhave contradictory discussions, contradictory opinions on what the sustainable buildingand green building implies.(Refer Slide Time: 13:48)Now, green building often looks at the environmental dimension while sustainablebuilding looks at all the three-dimensions in an equal capacity. However, when we go onto monitor it as I was mentioning initially also that environmental aspects are the most tangible one. They are the easiest to monitor, they are the easiest to calculate, quantifyand hence benchmark unlike the social benefits.For example, place making, identity, sense of belongingness. Now, it is often difficult toquantify and hence we do not have the benchmarking or rating systems developed forsustainable architecture as we have for the green buildings.(Refer Slide Time: 14:55)Now, when I repeatedly talk about this difference between green and sustainable let meclarify it by taking an example one which is a certified green building and a very highlyacclaimed green building versus a sustainable building. (Refer Slide Time: 15:12)So, let us start with this green building. So, the example that I have taken is of SuzlonOne Earth. Now, this campus Suzlon One Earth which is designed by ChristopherCharles Bonanza is also a green certified building. Now, Suzlon itself being the companywhich is involved in renewable energy, they have their entire campus which is 100percent renewable energy campus.They have installed windmills, they have added solar photovoltaic to generate the entireelectricity usage within the campus, on the campus and part of it off the campus.(Refer Slide Time: 16:00) So, they have all these on site and off siteoff-site wind turbines and photovoltaics whichcater to these needs.(Refer Slide Time: 16:03)They have hybrid solar chargers which interchange between the mode of renewableenergy from wind to solar depending upon the availability.(Refer Slide Time: 16:16)Huge areas are covered. (Refer Slide Time: 16:20)So, that is the main point of this entire campus when and that it becomes a net 0 campusit does not draw any energy from the grid because they generate 100 percent of theirenergy on site or off site, but of their own. This is the production side; however, at thedemand side they have managed with very good systems – the first one being the correctorientation of the building.So, the building has been oriented in such a manner that all their workspaces are day litalmost throughout the day without glare and without direct sun penetrating into theinteriors. (Refer Slide Time: 16:59)The second important aspect is the use of materials. This particular building isconstructed on a hillside hillock and the material which was used in the building was theone which was excavated from the site itself not 100 percent of it, but a large part of thebuilding material came from the site itself.(Refer Slide Time: 17:29)The next one is lighting because of the correct orientation and also the design forexample, the skylights that we can see and of the windows at a high level the entireworkspace is they lit without causing glare to the workspaces and without the use the need of any artificial lighting throughout the day. So, majority of the workspaces aredesigned to ensure daylight.(Refer Slide Time: 17:57)The next is landscape. So, they have used the native tree species all around the campuswhich are also requiring less of maintenance and water.(Refer Slide Time: 18:17)The next and one of the most important ones is water management. They recycle the 100percent waste water on the site and the same water is fed back into the system for userslike flushing. So, there is a dual piping system. The water is also used for landscaping the same water and hence the entire water consumption the loop is a closed loop with verylittle drawing of water from the ground or from the municipality.(Refer Slide Time: 18:59)(Refer Slide Time: 19:00)Now, we compare this building Suzlon One Earth which is a green building highlyenergy intensive, but generates 100 percent of its energy on site and off site. It consumesa lot of water, but recycles 100 percent of the water to keep it within the loop it haslandscape which is managed, but the native trees have been used. Now, compare this building with this primary school which is in Gando, Burkina Faso.This is a primary school which was built for the local children for the community.(Refer Slide Time: 19:41)Now, for construction they have used these compressed earth blocks; these bricks whichwere made with the help of community participation. The parents of these children cametogether to make these bricks. The stone is locally available the climate is climaticcondition is a very- very harsh and this school was constructed for a veryunderprivileged community which was living around.So, the construction materials which are used are very low on embodied energy. Theyare made out of materials which available locally and the type of construction which isused which is this double roof. (Refer Slide Time: 20:30)So, a brick slab roof and it has a double roof on top of it which helps to keep the indoorenvironment comfortable as it takes away all the heat; this cavity takes away all the heatwhich is accumulated which is gained from the solar radiation. So, this cavity betweenthe top surface of the roof the second roof and the mass the roof mass helps to keep thetemperatures low in this building.(Refer Slide Time: 21:07)Now, this entire building was actually as proposed as a school extension and, served thecommunity which was living around. (Refer Slide Time: 21:14)The unique design of windows to ensure that the indoors are day lit and no artificiallighting systems are employed into this building. It is naturally ventilated without anymechanical systems based upon the thermal comfort needs of the community. And itprovides a comfortable thermally comfortable environment indoors.(Refer Slide Time: 21:42)The material which is these wood logs which are used to create the roof are also locallyprocured but, since it is a dry region not much of forest is available. So, this has beenused judiciously not in huge quantities, the main material being earth. (Refer Slide Time: 22:05)(Refer Slide Time: 22:11)This is for roof where the indoors beautiful aesthetics has been achieved at no cost. So,this kind of arrangement these this beautiful aesthetic arrangement has been achievedwithout spending a lot towards materials and by engaging people by involving people indesigning and also constructing. (Refer Slide Time: 22:32)Theseis is the these are the quarters for this staff where the water management has beenensured that all these domical roofs all these vaulted roofs through these vaulted roofsthe water collects through these channels these drains and is collected in a center pointand is used for consumption in this entire small complex of the primary school. So, noexternal water is consumed.Now, if we compare these two buildings Suzlon One Earth in Pune and this primaryschool in Burkina Faso – one is an example where the consumption is huge, but thegeneration of the resource for example, energy is also happening simultaneously whileon the other hand we have an example this primary school which consumes zero energy.So, it does not require to generate it. It consumes very little amount of water which therequirement for which is met through the collection of rainwater.Besides that, it has an added benefit it has an added aspect which is fulfill which is ofsocial benefit where the building is constructed for an underprivileged community, thepeople are involved in not just the designing, but also the construction. So, people own it.There is a sense of belongingness because people have constructed it, people own thesebuildings. It does not require to be secured,be secured; it does not require to be logged.That is why the building remains open all the time. So, that is in true sense a sustainablebuilding. So, the difference between sustainable building and green building is evident where forgreen buildings we are focusing only on the environmental aspects while in a sustainablebuilding we are focusing not focusing, but the human beings, the users are at the centerof it and for these human beings we create architecture which is environmentallyresponsive.Another thing which we can see here is the affordability the economic affordability.Now, this office building of Suzlon One Earth is outstanding as far as environmentalaspects are concerned, but it may not be affordable a model of affordability. However,this one is out and out affordable because there is no cost which is going in hardly anycost.So, we very clearly know when we are talking about sustainable architecture and we aretalking about green architecture, green buildings these are two synonymous very close,but distinct terminologies, distinct philosophies. In the next lecture onwardsonwards, wewill discuss about some of the technical aspects of these green building.So, we will shift our focus from sustainable buildings more towards green buildingsbecause that is more tangible and more doable. So, we will discuss about the variousconcepts, technical concepts which go as part of green buildings and understand theseconcepts and how to deliver themThank you; see you in the next lecture. Bye-Bye.