GREEN PRE ENGINEERED BUILDINGS

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1 GREEN PRE ENGINEERED BUILDINGS By D.V.L.VARDHAN

2 INTRODUCTION: The National Geographic Society in association with GlobeScan, an internationally reputed poll firm developed the Greendex. It is a rating system that has been incorporated to gauge the extent of impact that consumption patterns have on the environment. The survey was conducted in 17 countries in 2009 and the results were quite interesting. The developing economies like India, Brazil and China had topped the charts whereas the developed economies like US, Canada and Japan languished at the bottom. In fact India was rated as the greenest country in the world. Greendex Map of the World The rating syste m depicts the shortfall in the standard of living in the developing economies and the high emissions associated with life styles in the developed economies. The developing economies will have to take a course where the economic outlook improves but not the emissions attached with it. On the other hand developed economies have to focus on a lesser emission based consumption pattern. Therefore the need of the hour is to look for concrete solutions that cater to the exigencies. The measures that need to be taken should be wide ranging, encompassing several sectors like energy, transportation, logistics, industries, commercial spaces etc. Moreover buildings are considered to be the major source for emissions throughout their life cycle. Therefore a very pertinent paradigm of green buildings has been evolved to negate the malignant effects associated with them.

3 GREEN BUILDINGS A Green Building, also known as a sustainable building, is a structure that is designed, built, renovated, operated, or re-used in an ecological and resource efficient manner. Objectives of a green building: Protecting occupant health Improving employee productivity Using energy, water and other resources more efficiently Reducing overall impact to the environment Optimal environmental and economic performance Satisfying and quality indoor spaces CONSIDERATIONS FOR GREEN BUILDINGS Control erosion to reduce negative impacts on water and air quality Reduce pollution and land development impacts from automobile use Limit disruption of natural water hydrology by reducing impervious cover, increasing on-site infiltration and managing storm water run-off Encourage and recognize increasing levels of self supply through renewable technologies to reduce environmental impacts associated with fossil fuel energy use Provide a high level of individual occupant control of ventilation and lighting systems to support good health, better productivity and a comfortable atmosphere Provide a connection between indoor spaces and outdoor environment through the introduction of sunlight and views into the occupied areas of the building

4 Parameters for a Green Building: The following aspects of the building design are looked into in an integrated way in a green building: Site planning Building envelope design Building system design HVAC(heating ventilation and air conditioning), lighting, electrical, and water heating Integration of renewable energy sources to generate energy onsite. Water and waste management Selection of ecologically sustainable materials (with high recycled content, rapidly renewable resources with low emission potential, etc.). Indoor environmental quality (maintains indoor thermal and visual comfort and air quality) RATING SYSTEM FOR GREEN BUILDINGS At present in India there are two rating systems, LEED GRIHA LEED RATING SYSTEM: Leadership in Energy and Environmental Design (LEED) is a rating system developed and managed by the US Green Building Council (USGBC). Buildings are rated as Platinum, Gold, Silver or Certified based on fulfillment of certain criteria. The LEED rating system in US exists for various sectors like New commercial construction Major renovation projects Existing building operation and maintenance Homes Schools Commercial Interiors LEED ratings for health care and labs are on the anvil.

5 INDIAN SCENARIO: The Confederation of Indian Industries (CII) and Godrej group had collaborated to set up the Indian Green Building Council at Hyderabad. IGBC basically facilitates the LEED ratings of the USGBC in India. They were launched in IGBC offers rating systems in the following formats IGBC GREEN HOMES IGBC GREEN FACTORY BUILDING LEED INDIA FOR NEW CONSTRUCTION LEED INDIA FOR CORE AND SHELL IGBC GREEN FACTORY BUILDING RATING SYSTEM: The principal idea behind conceptualizing such a rating system is to provide impetus for green and sustainable factories. Benefits Reduction in usage of energy (30-40 %) Reduction in usage of water resources (20-30 %) Reduction in green house gas emissions Better handling of waste products Improvement in the productivity of workers Improvement in the health and safety of workers. The IGBC Green factory rating system caters to new factories and existing factories as well. The IGBC Green factory rating system looks into the following parameters Site Selection and Planning Water Conservation Energy Conservation Material conservation Indoor environment quality and occupational health Innovation and design process

6 LEAD INDIA NC In India 20 % of the electricity is consumed by buildings. Urbanization has contributed towards this cause. With economic progress the emissions associated with buildings are going to rise. Thus IGBC has come up with LEED INDIA NC rating. It is for commercial, institutional and high rise residential buildings. It tries to address issues like Sustainable Sites Water Efficiency Energy & Atmosphere Materials & Resources Indoor Environment Quality Innovation & Design Process GRIHA RATING SYSTEM GRIHA is an acronym for Green Rating for Integrated Habitat Assessment. It is tool that has been developed by TERI and has been adopted by the Ministry of New and Renewable Energy GRIHA is a rating tool that helps people assesses the performance of their building against certain nationally acceptable benchmarks. It evaluate s the environmental performance of a building holistically over its entire life cycle, thereby providing a definitive standard for what constitutes a green building POINT SYSTEM FOR GRIHA Points scored Rating One star Two star Three star Four star Five star

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8 POINTS FOR IGBC GREEN FACTORY CERTIFICATION LEVELS Certified Silver Gold Platinum

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12 GREEN PRE ENGINEERED BUILDINGS Pre engineered buildings per se are environmentally benign to a certain degree. They negate the usage of buildings materials that have considerable amount of emissions. For example in a typical PEB the usage of cement and concrete is minimal when compared to a conventional building. There are some innate features of a PEB which brings it close to being a green product. Some of them are: The principal building material that is used in a pre engineered building is steel. Steel has the greatest advantage of being both recycled and recyclable Pre engineered buildings are resource optimized. PEB structures are made using proprietary software that optimizes the inputs. The precision thus obtained with the help of software can save a lot of steel, thus reducing the costs. The pre engineered buildings are light in weight compared to other buildings, thus making the foundation more sustainable. Special reflective materials and coatings can reduce the heat absorption capacity of the building. For example Cool metal roofing has high reflectivity and the loss is minimal over its life. Insulation in PEB can regulate the temperature inside the building, thus regulating the usage of energy. But in order to be rated as a green building emphasis has to be laid on several other aspects and better packaging is also needed to be done in order to be certified by a rating agency. Markets in India are not yet well verse in the practices that are followed for a typical green PEB. On the other hand certain companies, especially in US seem to have done considerable amount of work in this regard. Therefore in order to gain a perspective it would be pertinent to look at these companies to try and understand the products and services they offer. The companies which are active in the field of green PEB are Nucor, NCI etc. NUCOR Nucor is the largest steel recycler in the US. In 2008 Nucor recycled a quantity of scrap steel in excess of 20 million tons. Nucor's steel making processes are supposed to have lower emissions than integrated steel making operations. Nucor's energy consumption per ton of steel produced is much lower than that of integrated mills

13 Nucor offers certain products and services which help the customer obtain LEED ratings for the building. We should note that the LEED Rating System rates the aggregate system of the building and individual components of the building do not, by themselves earn points How Nucor facilitates LEED ratings Recycled steel Nucor buildings are made from recycled steel Nucor uses Electric Arc Furnace technology at its steel recycling facilities.eaf use scrap steel as major feedstock unlike blast furnaces that use mined ore. Recycled Steel Content of Nucor Products Nucor bar product 97.7 % Nucor beam products 76.2 % Nucor plate products 92.5% Nucor sheet products 70.2 % Total Nucor steel combined 89.7 % Heat Island Effect NBS offers two standard white (SP Polar White or Kynar Regal White) CFR finish options that exceed the LEED Solar Reflectance Index (SRI) requirement of 78. Use of Regional Materials Nucor has several plant sites scattered in US. This facilitates use of regional materials, thus reducing the shipment costs and associated emissions. Recyclability The steel that is used by Nucor are 100 % recyclable.

14 Points Earned By Using Nucor s Products LEED Section * Subject Potential Points NBS Contribution MR Credit 4.1 & 4.2 Recycled Content 2 NBS Recycled Content over 89% SS Credit 7.2 Heat Island Effect: Roof 1 NBS Offers 2 roof paints with Solar Reflectance Index (SRI) over 78 MR Credit 5.1 & 5.2 Use of Regional Materials 2 NBS multiple plant locations and Nucor domestic steel mills can often contribute to the use of regional materials. This varies based on the job site. The local plant will assist in determining regional content MR Credit 3.1 & 3.2 Materials Reuse 2 All NBS steel materials are 100% recyclable in the future. NCI LEED - POINT CHART This chart presents some of the ways NCI Metal Building products can help you earn points toward LEED Certification. LEED -NC Metal Building Credit Guide 1 Name Description Number of Points 2 Reason SS Credit 5.1 Site Development: Protect or Restore Habitat 1 Being shop fabricated, NCI metal buildings allow field assembly using a minimal work area. SS Credit 7.1 Heat Island Effect: Non-roof Up to 2 (1 plus 1 Exemplary Performance point 4 ) By deploying parking covers with NCI roof products, 1 point is earned for 50% of spaces covered, and an exemplary performance point can be earned for 100% of spaces covered.

15 SS Credit 7.2 Heat Island Effect: Roof 1 Our Snow White, Ivory, Bone White, and Solar White colors meet the low-slope requirement and all NCI colors meet the steep slope requirement of this credit. EA Credit 1 Optimize Energy Performance Up to 10 By utilizing NCI cool roof colors 3 and insulated metal panels in your energy models, you can reduce external loads and downsize HVAC equipment to help get the most points possible. MR Credit 4.1 and MR Credit 4.2 Recycled Content: 10% and 20% Up to 2 Depending on the nature of the project, NCI metal buildings will contain between 25% and 60% recycled steel by weight 5. (Post-consumer + ½ Pre-consumer) On a typical project, this will represent about 40% of our contract value. MR Credit 5.1 (under LEED-NC 2.0 and 2.1 only) Regional Materials : 20% Manufactured Regionally 1 NCI is comprised of a network of companies operating 39 manufacturing facilities across the United States and Mexico. This network maximizes the amount of material manufactured within a 500 mile radius of most points in the US. EQ Credit 8.1 Daylight and Views:Daylight 75% of spaces 1 NCI s insulated light transmitting panels are excellent diffusers when utilized on the roof or walls. Thus PEB companies in India can take up similar measures and provide green solutions. Such measures will help the companies in diversifying their product base and at the same time position themselves as an environmental friendly company.