Introduction to Green Building-
The design, construction, operation, and maintenance of buildings normally require enormous amounts of energy, water, and raw materials, generating large quantities of waste and causing air and water pollution.
Whereas green building is the only answer through creating healthier and more resource-efficient models of construction, renovation, operation, and maintenance.
Green Architecture and sustainable buildings are considered a modern trend in architectural thinking which manipulates the relationship between the building and the environment.
Generally, office buildings are one of the highest types of buildings in energy consumption compared to other building types.
So it’s very important for an architect to implement specific strategies in order to decrease energy consumption, especially in this type of building, by using renewable energy sources such as solar energy, wind energy, and other sources which contribute to electric energy rationalization.
What is Green Building?
A Green building or sustainable building is a structure which is designed, constructed, operated, or reused in an ecological and energy-efficient manner.
Concept of Green Buildings-
The concept of Green building integrates a variety of strategies during the period of Design, Construction, Maintenance, and Operation of buildings.
Construction is an element of civilization which is increasing continuously and thereby requires lots of natural or manmade materials to fulfill the demand.
Manufacturing of construction materials like Cement, Conventional brick, steel, etc.
These materials produce a large amount of CO2 and other greenhouse gases which are hazardous or toxic in nature and cause environmental and health-related problems.
So it is today’s demand to acquire good construction practice and energy efficient material which helps in less production of greenhouse gases and save energy.
Principle of Green Buildings-
The green building design process begins with a deep understanding of the site in all its beauties and complexities.
An ecological approach to design aims to integrate the systems being introduced with the existing on-site ecological functions performed by nature.
These ecological functions provide habitat, respond to the movements of the sun, purify the air as well as catch, filter, and store water.
Designers can create features in their buildings that represent the functions of particular ecosystems. Species that thrive in natural ecosystems may also utilize habitats created in man-made structures.
Creating new habitats on structures in urbanized areas is especially important to support bio-diversity and a healthy ecosystem.
The objective is to evolve a strategy to reduce the energy used in buildings so as to reduce energy costs and greenhouse gas emissions into the earth’s atmosphere.
The concept of Green Buildings envisions a new approach to saving water, energy, and material resources in the construction and maintenance of buildings and can reduce or eliminate the adverse impact of buildings on the environment and occupants.
Design considerations of Green building Results in Reduced site disturbance, Wastewater management, and Stormwater management.
Landscape and Exterior Design to reduce heat islands, Light Pollution Reduction, and Reduced Car dependence through car parking provision.
A green building is designed, constructed, and operated to minimize the total environmental impacts while enhancing user comfort and productivity.
Features of Green Building-
A green building includes environmental considerations in each stage of the building construction and focuses on the design, construction, operation, and maintenance phases.
Green buildings typically incorporate superior air quality, abundant natural light, access to views, and noise control which benefits building occupants, making these buildings better places to work or live.
Here are some most highlighted features of Green Buiding-
- Air tightness and vapour barrier in building walls and surfaces
- Waste reduction
- Enthalpy recovery of exhaust air
- Low solar heat gain coefficient of glass
- Daylight-controlled lighting systems
- Occupancy sensors
- Water-efficient fittings
- Rain-water harvesting
- Materials recovery facility (MRF)
- Site sustainability
- Geothermal Heating and Cooling
- HEPA (High-efficiency particulate arrestance)
- CO2 Controlling ventilators
- VSD(Variable Speed Drives)
- Use of solar panels
- Solar thermal collectors
- Greywater/Blackwater Recycling
- Wind Turbines
1. Air tightness and vapour barrier in building walls and surfaces-
Walls that are able to keep out moisture and humidity from outside will make the building naturally cooler.
Because of this, air-conditioning systems will not have to work so hard to cool down the building and thus lowers electricity costs.
2. Waste Reduction-
Pollution control measures adopted and implemented on the project sites during construction activities, Green buildings aim to reduce the amount of material being sent to landfills during construction.
3. Enthalpy recovery of exhaust air-
A device called an enthalpy wheel recovers cooled air from the inside and uses the coolness of this “spent” air to cool fresh air from outside.
The process also dehumidifies the air from outside. This is a cost-efficient way to improve indoor air quality and lessen energy consumed by air-conditioning systems.
4. Low solar heat gain coefficient of glass-
Solar heat gain coefficient(SHGC) is the amount of solar radiation that enters through glass and is released as beat inside a building.
The lower the SHGC, the less solar heat it transmits, and the cooler the building. This also lowers electricity costs because air-conditioning systems don’t have to do all the work.
5. Daylight-controlled lighting systems-
This type of lighting system has sensors that can detect daylight. During the day, the sensor switches off the lights since there is enough light from the sun.
When the sun sets, the system will switch the lights on. This way, the use of artificial lighting during the daytime is reduced.
6. Occupancy sensors-
This lighting system only turns on when it senses people in the room. This technology can also be found in escalators that activate only when there are people riding on them.
7. Water-efficient fittings-
The latest faucets and flush mechanisms use less water to do the same thing.
8. Rain-water Harvesting-
A structure catches rainwater and then stores it in big containers. The water can then be used to water plants, flush toilets, or supply cooling towers.
9. Materials recovery facility (MRF)-
An MRF is where the building’s garbage is segregated into biodegradable, recyclable, non-recyclable, and special or hazardous waste.
Biodegradable waste can be composted and used as fertilizer for the building’s plants.
A significant portion of the building’s unpaved area is devoted to vegetation. This helps reduce the heat urban island effect-when concrete surfaces so common in urban areas absorb heat from the sun and radiate it to the surroundings.
Plants also help absorb some rainwater which would otherwise go to sewers and drainage, later on contributing to flooding.
11. Site Sustainability-
The building’s design, construction, and operation practices should have minimum impact on ecosystems and water resources.
12. Geothermal Heating and Cooling-
The underground is an excellent heat sink in summer and an excellent heat source in winter. Geothermal heat pumps take advantage of this providing heating and cooling for buildings with a lower kWh consumption than other methods.
Indoor heating and cooling are provided normally with hydronic piping, air-handling units, and air ducts.
The geothermal heat pump uses a secondary piping circuit that goes underground, to collect or reject heat as needed.
13. HEPA (High-efficiency particulate arrestance)-
HEPA stands for high-efficiency particulate arrestance. HEPA filters are among the best available, capturing 99.97% of particles with a size of 0.3 microns or more.
These filters remove many pollutants and allergens from the air, improving indoor air quality.
14. CO2 Controlling Ventilators-
Since human metabolism produces carbon dioxide, occupancy can be correlated with the CO2 concentration in the air.
Ventilation can be controlled with CO2 sensors, reducing airflow in proportion to occupancy to achieve energy savings.
15. VSD(Variable Speed Drives)-
Variable speed drives(VSD) are devices that modify the voltage and frequency supplied to a motor, allowing it to operate below-rated rpm.
VSDs are very useful in motors that drive fans and pumps since these devices are often subject to part-load conditions. They are also known as variable frequency drives (VFD).
16. Use of solar panels-
Solar panels are among the most promising building upgrades if you have plenty of rooftop areas available.
They normally come with a 10-year warranty for manufacturing defects and a 25-year warranty for energy generation, in addition to having simple maintenance needs.
The payback period of solar panels only represents a small fraction of their service life. Simple maintenance. The main requirement is keeping panel surfaces clean and free of shadows.
May be eligible for incentives from the government or utility companies.
17. Solar thermal collectors-
Solar radiation is used directly for domestic hot water instead of electricity generation. With this building upgrade, you can rely less on your gas-fired water heater.
There may be a slight pumping cost in taller buildings since water has to reach the rooftop, but it is much less than the ongoing cost of a water heater.
However, Solar thermal collectors also harness sunlight.
18. Greywater/Blackwater Recycling-
The concepts of greywater and blackwater are used to describe water that has already been used in plumbing fixtures.
Blackwater includes water from all fixtures, while greywater excludes the water discharged from toilets.
Although greywater is polluted with cleaning agents and grease, it can be collected and reused for purposes such as flushing toilets or outdoor watering.
Blackwater can also be recycled for some purposes, but it requires special treatment.
LED uses over 30% less power consumption than fluorescent, over 50% less than HID, and over 80% less than incandescent.
LED also Reduced the cooling load for AC and refrigeration equipment. LEDs have a Long service life and almost no maintenance is required.
20. Wind Turbines-
A single wind turbine results in a lower cost per kilowatt. Electricity generation is enhanced with a taller tower since airflow is more stable as height increases.
Smaller turbines are closer to the ground and susceptible to the turbulence caused by trees and constructions.
Electricity savings, zero generation cost after the payback period. May be eligible for incentives from the government or utility companies.
Green Building Materials used in Construction-
The materials used while constructing a green building are listed and described below-
- Earthen Materials
- Engineered Wood
- Structural insulated panels (SIPs)
- Insulated Concrete Forms
- Straw Bale
- Earth Bags
- Slate Roofing
- Natural Fiber
- Natural Clay
- Non-VOC Paints
- Natural Fiber Floor
- Fiber Cement
- Triple-Glazed Windows
- Paper Insulation
- Solar Ties
- Compressed Earth Brick Block
- Marble slurry bricks
- Ferro cement wall panels
- Compressed Earth block
- Sand Lime Brick
1. Earthen Materials-
Earthen materials like adobe, cob, and rammed earth are being used for construction purposes.
For good strength and durability- chopped straw, grass, and other fibrous materials, etc. are added to the earth.
Even today, structures built with adobe or cob can be seen in some remote areas.
2. Engineered Wood-
Wood is one of the most famous building materials used around the world But in the process of conversion of raw timber to wood boards and planks, most percentage of the wood may get wasted.
This wastage can also be used to make structural parts like walls, bounds, doers, etc in the form of engineered wood.
Unlike solid wood engineered wood contains different layers of wood. Usually, the middle layers are made of wood scraps, softwood, wood fibers, etc.
Bamboo is one of the most used multipurpose and durable materials used in construction. These trees grow faster irrespective of climatic conditions. So, it makes it economical as well.
They can be used to construct frames or supports, walls, floors, etc.
They provide a good appearance to the structures. Bamboo is such a promising building material for modern buildings since it is a combination of tensile strength, lightweight, and fast-growing renewable nature.
Used for framing buildings and shelters, bamboo can replace expensive and heavy imported materials and provide an alternative to concrete and rebar construction, especially in difficult-to-reach areas, post-disaster re-building, and low-income areas with access to naturally locally-sourced bamboo.
4. Structural insulated panels (SIPs)-
Structural insulated panels (SIPs) consist of two sheets of oriented strand boards or flake boards with a foam layer between them.
They are generally available in larger sizes and are used as walls for the structure.
Because of their large size, they need heavy equipment to install however, they provide good insulation.
5. Insulated Concrete Forms-
Insulated Concrete Forms Insulated concrete forms contain two insulation layers with some space in between them.
This space contains some arrangements for holding reinforcement bars, after placing reinforcement, concrete is poured into this space.
They are light in weight, fire resistant, low density, and have good thermal and sound insulation properties.
If wood is abundantly available and easily accessible to the site of construction, cordwood construction is recommended.
It requires short and round pieces of wood which are laid one above the other, width-wise, and are bonded together by a special mortar mix.
They are strong, environmentally friendly, and also give a good appearance to the structure.
7. Straw Bale-
Straw bale is another green building material which can be used as framing material for buildings because of its good insulating properties.
They can also act as soundproof materials. Non-load bearing walls of the straw bale can be used as fill material in between columns, in beams framework is recommended.
Since air cannot pass through them, straw bales also have some resistance to fire.
8. Earth Bags-
Earthbags or sandbags are also used to construct walls of a structure.
These types of structures can be seen in military bases, near banks of water resources, etc.
Generally, bags made of burlap are recommended but they may not very easily and hence. polypropylene bags are used nowadays.
9. Slate Roofing-
Slate is a naturally formed rock which is used to make tiles. Slate tiles have high durability and they are used as roofing materials.
Slate roofing is preferred when it is locally or cheaply available.
Steel roof panels and shingles are highly durable and they can be recycled again and again. So, these are the best choices for green roofing materials.
Thatch is nothing but dry straw, dry water reed, dried rushes, etc. These are the oldest roofing materials which are still in use in some remote locations of the world and even in cities for aesthetic attractions.
It is cheaply available for roofing and is a good insulator too.
Roof panels made of composite materials such as foam or cellulose layer sandwiched between two metal sheets or two plastic sheets also come under green building materials.
They are light in weight, inexpensive and provide good insulation for the structure and save energy.
13. Natural Fiber-
Natural fibers like cotton and wool can also be used as insulation materials. Recycled cotton fibers or wool fibers are converted into a batt and installed in preformed wooden frame sections.
Polyurethane foam is available in the form of spray bottles. They are directly sprayed onto the surface or wall or to which part insulation is required.
After spraying it expands and forms a thick layer which hardens later on. They offer excellent insulation and prevent leakage of air.
15. Fiber Glass-
Fiberglass is also used for insulation purposes in the form of fiberglass batts.
Even though it contains some toxic binding agents, because of its super insulation property at low cost it can be considered a green building material.
Cellulose is a recycled product of paper waste and it is widely used around the world for insulation purposes in structure.
It acts as a good sound insulator and is available for cheap prices in the market.
Cork is also a good insulator. Boards or panels made of cork are available in markets. A great amount of electrical energy can be saved by corkboard insulation in winter.
These corkboards are also good for sound insulation.
18. Natural Clay-
Plastering of walls can be done using natural clay rather than other gypsum-based plasters. Natural clay plaster with proper workmanship gives a beautiful appearance to the interior.
19. Non- VOC Paints-
Non-VOC paint or green paint is recommended over VOC-containing paints.
The presence of Volatile Organic Compounds (VOC) in paint reacts with sunlight and nitrogen oxide resulting in the formation of ozone which can cause severe health problems for the occupants.
If non-VOC paint is not available then paint with very low-VOC content in it is preferable.
20. Natural Fiber Floor-
Naturally occurring materials like bamboo, wool, cotton fiber carpets, cork, etc. can be used for flooring purposes.
21. Fiber Cement-
Fiber cement boards are made of cement, sand, and wood fibers. For exterior siding, fiber cement boards are a good choice because of their cheap price, good durability, and good resistance against fire.
Stone is a naturally occurring and long-lasting building material. Some Stone structures built hundreds of years ago are still in existence without much abrasion.
Stones are good against weathering hence they can be used to construct exterior walls, steps, exterior flooring, etc.
23. Triple Glazed Window-
It is a super efficient material that stops heat to enter the building from direct sunlight.
24. Paper Insulation-
Made from recycled newspapers and cardboard which is insect resistant and fire retardant.
25. Solar Ties-
Act as a protective covering for buildings and spend a large portion of the day absorbing energy.
26. Compressed Earth Brick Block-
Use to construct a building that is aesthetic, efficient, and easy to build. Energy efficient excellent surface finish Cost efficient technology plastering is not required good thermal insulation.
27. Marble Slurry Bricks-
Use for walling as an alternative to conventional clay bricks these are energy efficient high volume utilization of wash stronger than clay bricks, fire resistant basic high load bearing capacity.
28. Ferro cement wall panels-
Use for walling is particularly suitable where speedy construction is required. These are energy-efficient, cost-effective technology regularity in shape and size components that can be retrieved for construction.
29. Compressed Earth block-
It is a highly compressed earth block or brick. These bricks are mechanically pressed with a pressure of about 3,000 psi at this pressure original volume of soil reduces by about half.
Compressive earth blocks are inexpensive and best for non-load-bearing structures. A coat of Polycarbonate varnish is required to avoid erosion due to wet weather.
30. Sand Lime Brick-
Sand lime brick is a pressed brick made of 90% sand and 10% hydrated lime and kept in an autoclave for steam curing.
These bricks are of uniform shape and size which requires less mortar for masonry.
Standards of Green Buiding-
Standards for Green Buildings Four of the largest and most recognized green labeling programs are:
- Energy Star
- Green Globe
- Green Seal
Each are administered by different organizations, has its own rating criteria, and focuses most heavily on different issues.
By looking at all four of these, one can begin to see overlaps and shortcomings. One can begin to develop a more holistic approach to defining a truly green material.
LEED is an internationally recognized green building certification system.
LEED provides third-party verification that a community or building was designed and built using strategies aimed at improving performances in energy savings, water efficiency, CO2 emissions/ reductions, improved indoor environmental quality, and stewardship of resources and sensitivity to their impact.
Developed by the U.S. Green Building Council, LEED provides a framework for implementing measurable green building design, construction, operations, and maintenance solutions.
It works throughout the building lifecycle. Certification is achieved through the third-party independent Green Building Certification Institute.
LEED Rating Systems are applicable to-
- New Construction
- Existing Buildings- Operations + Maintenance
- Commercial Interiors
- Core and Shell
2. Energy Star-
- A government-backed organization focusing on improving energy efficiency, administered by the US Environmental Protection Agency and the US Department of Energy.
- Standards for Energy Star-rated buildings are set by the EPA. Their motto is “Energy efficiency comes first”.
- Founded in 1992, Energy Star began as a labeling program that only rated consumer products.
- Products like household appliances and air conditioning units with the Energy Star label now save between twenty and thirty percent of energy.
3. Green Globe-
A guidance and assessment program that offers realistic and achievable ways to increase the sustainability of commercial buildings, Administered by the Green Building Initiative in the US.
The most important components of the Green Globe program are:
- Comprehensive environmental assessment protocol
- Software tools that speed and ease online assessment
- Best practices guidance for green construction and operations
- Experienced green building assessors
4. Green Seal-
A non-profit, third-party certifier and standards development party.
The largest US-based ecolabelling organization The U.S. member of GEN (Global Ecolabelling Network), which consists of 26 of the world’s leading ecolabelling programs.
Develops standards from green cleaning products to lodging Green Seal uses life cycle assessment, evaluating products from raw materials extraction to manufacturing and use to disposal or recycling.
If a product meets Green Seal standards, it will be awarded the Green Seal. This organization works with the marketplace in an effort to create a “more sustainable world”.
How Can We Make Our Buildings Green-
There are a number of ways to make a building green. These include:
- Taking an intelligent approach to energy
- Safeguarding water resources
- Minimizing waste and maximizing reuse
- Promoting health and wellbeing
1. Taking an intelligent approach to energy-
- Minimizing energy use in all stages of a building’s life-cycle, making new and renovated buildings more comfortable and less expensive to run, and helping building users learn to be efficient too.
- Integrating renewable and low-carbon technologies to supply buildings’ energy needs, once their design has maximized inbuilt and natural efficiencies.
2. Safeguarding Water Resources-
- Exploring ways to improve drinking and wastewater efficiency and management, harvesting water for safe indoor use in innovative ways, and generally minimizing water use in buildings.
- Considering the impact of buildings and their surroundings on stormwater and drainage infrastructure, ensuring these are not put under undue stress or prevented from doing their job.
3. Minimizing waste and maximizing reuse-
- Using fewer, more durable materials and generating less waste, as well as accounting for a building’s end-of-life stage by designing for demolition waste recovery and reuse.
- Engaging building users in reuse and recycling.
4. Promoting Health and well-being-
- Bringing fresh air inside, delivering good indoor air quality through ventilation, and avoiding materials and chemicals that create harmful or toxic emissions.
- Incorporating natural light and views to ensure building users’ comfort and enjoyment of their surroundings, and reducing lighting energy needs in the process.
- Designing for ears as well as eyes. Acoustics and proper sound insulation play important roles in helping concentration, recuperation, and peaceful enjoyment of a building in educational, health, and residential buildings.
- Creating the right indoor temperature through passive design or building management and monitoring.
- Recognizing that the urban environment should preserve nature, and ensuring diverse wildlife and land quality are protected or enhanced, by remediating and building on polluted land or creating new green spaces.
- Looking for ways we can make our urban areas more productive, bringing agriculture into our cities.
- Adapting to our changing climate, ensuring resilience to events such as f flooding, earthquakes, or fires so that our buildings stand the test of time and keep people and their belongings safe.
- Designing flexible and dynamic spaces, anticipating changes in their use over time, and avoiding the need to demolish, rebuild or significantly renovate buildings to prevent them from becoming obsolete.
- Creating diverse environments that connect and enhance communities, asking what a building will add to its context in terms of positive economic and social effects, and engaging local communities in planning.
- Ensuring transport and distance to amenities are considered in the design, reducing the impact of personal transport on the environment, and encouraging environmentally friendly options such as walking or cycling.
- Exploring the potential of both ‘smart’ and information communications technologies to communicate better with the world around us. For example smart electricity grids that understand how to transport energy where and when it is needed.
- Seeking to lower environmental impacts and maximize social and economic value over a building’s whole life-cycle (from design, construction, operation, and maintenance, through to renovation and eventual demolition).
- Ensuring that embodied resources, such as the energy or water used to produce and transport the materials in the building are minimized so that buildings are truly low impact.
Advantages of Green Buildings-
Here are some major benefits of Green Buildings-
- Reduced operational energy
- Reduced water requirement
- The lesser volume of wastewater generation
- Resulting in lesser water pollution
- Less material usage Longer building life
- Lower maintenance costs use less natural resources as compared to a normal building
- Green buildings are generally costlier than normal buildings but only at the initial stage while the overall costs are much lesser than the normal buildings
- They consume less resources and improve the productivity of occupants
- Green buildings also entail higher real estate value.
- Incentives are also given by local government bodies in order to achieve a sustainable future
- Cost savings on utility bills for tenants or households (through energy and water efficiency)
- Lower construction costs and higher property value for building developers.
Green building benefits go beyond economics and the environment and have been shown to bring positive social impacts too.
Many of these benefits are around the health and well-being of people who work in green offices or live in green homes.
- Green Buildings have been proven to have a positive impact on the health of residents as they provide a balanced and optimal eco-system for residents, they have a positive effect on the productivity and well-being of those who occupy the building.
- Research suggests that better indoor air quality (low concentrations of CO, and pollutants, and high ventilation rates) can lead to improvements in the performance of an employee by up to 8 percent.
Disadvantages of Green Buildings-
Here are some major drawbacks of Green Buildings-
- High implementing costs.
- Lack of information.
- No known alternative chemical or raw material inputs.
- No known alternative process technology.
- uncertainty about performance impacts and lack of human resources and skills business at a competitive company decides to adhere to strict, self-imposed pollution standards.
- Since these buildings depend on the sun for energy, they need to be located in a position that will have the best sun exposure which may demand placing them opposite other neighborhood homes.
- The materials to build such buildings can be hard to find especially in urban areas where preserving the environment is not the people’s first option. Shipping these materials can then cost a lot more than a standard building.
- These buildings run on heat to generate power, so they are not designed for hot areas they do not have any ventilation systems, so air conditioners will be required.
- One of the most common disadvantages of Green Building is the additional cost incurred. This is due to the increase in the quality of construction methods and materials used.
- Apart from the initial cost of green building, finding a mortgage company or bank that offers loans for a building that is not built in the traditional way may be difficult.
- The time taken to complete a green building can also be viewed as a disadvantage. Green building projects encourage the use of recycled materials and trying to source these can add to the time to complete a certain stage of the build that the contractor and client haven’t allowed for in the project.
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Abhishek Tiwary is a blogger by passion and a Quality Engineer by profession. He completed his B.Tech degree in the year 2017. Now working in a reputed firm. He loves to share his knowledge with others.