- Green buildings are designed to reduce the overall impact on human health and the natural environment. these buildings are designed and constructed in such a way that it ensures less consumption of energy, save water, generate less waste, etc.
- Such buildings produce less pollution and environmental degradation substance hence protects occupant health.
- The green building concept is to construct a building in such a manner which is environmentally responsible and resource-efficient throughout its life.
- A developing country such as India is experiencing urbanization at a rapid pace. Nearly 34% of the population resides in urban areas, posing huge challenges for municipalities. The cities are experiencing huge construction activities, which is resulting in increased demand resources such as energy, water, material, while at the same time a lot of construction and solid waste is generated after buildings are occupied. The absence of larger policy and incentives to distribute the growth is further creating vulnerability
- Today the total world population is 8,000,000,000 (approx) and forests can absorb 900000 crores Kilograms every year. So it is our social responsibility to produce (900000 X 10000000 ) / 8000000000 = 1125 kg of (CO2 + CH4) per person per year
What civil engineers contribute
- In India, More than 26000 crore bricks are required per year and burning of bricks in a kiln produces 80 kg of CO2 gases (approx) per 1000 bricks. So we produce 2080 crore kg of CO2 from the burning of bricks and today’s population of India is 135 crore (approx). Therefore Each Indian unknowingly produces 15.5 kg of CO2 per year by using kiln bricks.
- Each year we produce 28 crore tonnes (approx) of cement and 1.25 tonnes of CO2 emits from 1 ton of cement production hence Each year we produce 35 crore tonnes of CO2 from the Cement industry. Each Indian unknowingly produces 260 kg of CO2 per year by using cement only.
Green Building Materials
Use of Geocement or Geopolymer cement
It is obtained by the chemical reaction between silicon and aluminum and the chemical reaction takes place through polymerization. Geocement is the cement that doesn’t require water for mixing and curing processes. It reacts with special types of binder, known as geobinder. Geocement and geobinder are mixed to form a hardened mass, called Geocrete. It is an alkali based cement that prevents bacterial growth and is ideal for sewerage pipes, This cement has a better acid resistance. It plays a vital role to reduce the global warming by reducing carbon dioxide emissions by using a liquid binder. As per research data the compressive strength of geocrete is more than that of normal concrete. the cost of geocement and geobinder is 10 to 15 percent higher than OPC but in the end, the cost of project may be lower due to less requirement of construction time and labor.
Use of fly ash based brick
Fly ash is a by-product of burned Fine particles of coal used in the thermal power plants. First Coal is grounded into the fine powder then it is mixed with diesel and fired into the boiler furnace by using a compressed air machine. after the combustion of coal it changes into coal ash. Based on Particle size, Coal ash can be divided into two subcategories, Fly ash (80%) and Bed ash (20 %). Bottom ash is a coarser particle in coal ash. Fly ash is the lightest particle of 0.0001 mm to 0.3 mm size ranges and spherical in shape. Fly Ash consists of inorganic materials mainly silica and alumina with As the name suggests, Bed ash settles on the bed of furnace however fly ash is a flying particle in the air. These flying particles are trapped and removed by Electrostatic Precipitator. This electrostatic precipitator is a large, industrial emission control instrument. It consists of discharge wire and collecting plates. A high voltage of 20 thousand to one lakh volts is applied in the discharge wire. These discharge wire form an electric field with collecting plates. this wire ionizes the gas around it. When fly ash is forced into the ESP with the help of Forced draft Fan, these ionized gases make negative charges to the fly ash particles. This negative charge particle is attracted by the Positive charge collecting plates where the particle gets neutralized. These neutralized particles are collected in the hopper by immediately hammering the collecting plates. Bituminous type coal is most commonly used in Indian thermal stations hence Class F type fly ash normally produced after burning bituminous type coal which shows pozzolanic property but rarely shows any self-hardening property. In India we produce 18 crore tones of fly ash every year. Self-hardening property can be achieved when It is mixed with slaked lime and forms a cementitious compound. Bricks containing fly ash (50%), lime (10%) and stone dust (40%) shows the bricks of compressive strength up to 8.8 N/mm2.
Use of Low VOC Paint in Green building
Use of volatile organic compounds ( petroleum or formaldehyde or heavy metal) based paint can cause asthma, allergies, Headache, irritate the eyes, nose and throat, nausea, and damage to the liver, kidneys, and central nervous system. some can cause cancer. VOC evaporates into the air for many days and It is the main cause of Indore air pollution. The amount of VOC in paint is limited to 250 grams per liter for latex paint. Hence low VOC or water-based paint shall be used
Use of Low emissivity glass, Tinted Glass, or Reflective Glass
Whenever there is a temperature difference between the two surfaces of window glass. The heat will migrate from the warmer surface of the glass to the cooler surface. So there is a thermal transmission. Heat transfer can be reduced by using glass with a Low-E coating. Low E coated glass can prevent the heat from going inside in the Summer and keeps the inside heat from going out in the winter and makes the room more comfortable.
Heat insulation of Building
- Timber can be used for heat insulation in the floor.
- Construction of the cavity wall is an option to insulate the wall from heat.
- but there are other options,
- to use of blankets made from mineral fibers including fiberglass or rock wool.
- to use of cellulose, fiberglass, or rock wool in the form of loose fibers that are blown using pneumatic equipment.
- Poly-iso-cyanurate and poly-urethane type foam insulation can be used for heat insulation
- Aluminum paints and aluminum foils can also be used for heat insulation.
Design requirements of Green Building
- use of heat-insulated glass in the window can reduce the thermal transmission.
- To reduce the catchment area, Rain gardens provide a good solution.
- Provision of Energy efficient appliances
- Construction of rainwater harvesting tank on the roof which can collect water, to be used to flush toilets, gardening, car washing, etc.
- Provision of the solar panel of 5 Kwh which can generate 20 units of electricity per day.
- Use of LED Light.
- Use composting to reduce biodegradable wastes like food scraps and convert them into fertilizer. It can be used in your garden.
- Use of smart LED bulbs, smart ceiling fan, and other appliances compatible with Alexa
The cost of Green building is 10 to 20 percent more than the cost of a regular building. but in the end, the savings may be higher due to less consumption of electricity, water, and less booking of an appointmentwithdoctor