GREEN BUILDING's: A OVER VIEW

GREEN BUILDING's: A OVER VIEW

Definition of Green Building:

"A green building uses less energy, water and natural resources, creates less waste and is healthier for the people living inside compared to a standard building”.

Green Building Basics:

Building "green" is an opportunity to use our resources in an efficient manner while creating healthier buildings that improve health, build a better environment, and most important of all provide cost savings.

What is Green Building?

A green building, also known as a sustainable building, is a structure that is designed, built, renovated, operated, or reused in an ecological and resource-efficient manner. Green buildings are designed to meet certain objectives such as protecting occupant health, improving productivity, efficient use of energy, water, and other resources more efficiently; and reducing the overall impact to the environment which is most important.

Benefits of Green Buildings?

A green building may initially cost more upfront, but saves through lower operating costs over the life of the building. The green building approach applies a project life cycle cost analysis for determining the appropriate up-front expenditure. This analytical method calculates costs over the useful life of the asset.

These and other cost savings can only be fully realized when they are incorporated at the project's conceptual design phase with the assistance of an integrated team of professionals. The integrated systems approach ensures that the building is designed as one system rather than a collection of stand-alone systems.

Some benefits, such as improving occupant health, comfort, productivity, reducing pollution and landfill waste are not easily quantified. Consequently, they are not adequately considered in cost analysis. For this reason, consider setting aside a small portion of the building budget to cover differential costs associated with less tangible green building benefits or to cover the cost of researching and analyzing green building options.

Even with a tight budget, many green building measures can be incorporated with minimal or zero increased up-front costs and they can yield enormous savings

Green building materials:

Building materials typically considered to be 'green' include rapidly renewable plant materials like bamboo and straw, lumber from forests certified to be sustainably managed, dimension stone, recycled stone, recycled metal, and other products that are non-toxic, reusable, renewable, and/or recyclable (eg Trass, Linoleum, sheep wool, panels made from paper flakes, baked earth, rammed earth, clay, vermiculite, flax linen, sisal, seagrass, cork, expanded clay grains, coconut, wood fiber plates, calcium sandstone. Building materials should be extracted and manufactured locally to the building site to minimize the energy embedded in their transportation.

Principles of Green Architecture:

principles of Green Architecture: Energy Efficiency

• Design passive solar energy facilities use energy-efficient appliances, solar panels and heat pump technology

• Use of computer sensor-controlled energy saving devices; like automatic dimmers for lighting and occupancy sensors to adjust air-conditioning automatically

• centralized plumbing, insulate cold/hot water piping

• Using energy saving lighting like CFL

• Install Monitor Power Management Software

• Use of low power computers

Principles of Green Architecture: Water Conservation

• collect rainwater for external use i.e. garden/washing car

• use water-conserving appliances including toilets, shower, taps, washing machine and dishwasher eg. Low flow faucets, water saving dual flush tanks

• reduce irrigation and surface water run-off

Principles of Green Architecture: Low Environmental Impact

• include water permeable landscape features

• enhance native bush and create edible gardens

• establish home recycling bins and garden composting.

Principles of Green Architecture: Building Materials

• Certified Wood - Specify wood from certified sustainably managed forests.

• select low volatile organic compounds (VOC) and toxic-free paints, finishes and adhesives

• use materials that permit the building membrane to 'breathe'

• apply natural floor surfaces such as tile, timber and linoleum

• use sustainable solid timbers rather than processed composite sheet materials

• use inert gypsum-based wall and ceiling linings.

• Rapidly Renewable Materials such as straw, bamboo and some woods

Principles of Green Architecture: Sustainability

• think globally -act locally

• reduce CO2 production, ozone and resource depletion, rainforest destruction and erosion

• encourage environmentally-friendly technologies and sustainable solutions

Principles of Green Architecture: Waste Reduction

• select materials using recycled components

• Design for re-use and recycling

• control and reduce waste and packaging

• reduce resource consumption.

Principles of Green Architecture: Health and Wellbeing

• meet the basic physical, emotional and spiritual needs of the occupants

• consider healthy lighting, colours and sound, controlled temperature and humidity and good indoor air quality to enhance the living environment

• reduce formaldehyde emissions and use pollution-fighting indoor plants

• create an asthma aware home i.e. no fitted carpets, reduced ledges, low-allergen gardens

• apply an integrated wiring system for lighting, power, security, fire alarm and audio facilities

• design a safe and user-friendly space

Principles of Green Architecture: Economic Performance

• consider the maintenance of space plus initial 'running costs' pay-back period

• strive for a balance between ecological integrity and economic viability.

Principles of Green Architecture: Community Support

• use local resources, skills, labour, crafts and art

• consider local facilities and utilities

Points for a Green office:

1. Open plan

2. Big atrium

3. Communal desks for multiple users

4. Terra cotta floor tiles and fly ash bricks are eco-friendly

5. Clear, white walls, eco-paints

6. Large, well-insulated double glazed windows, with solar shades

7. Solar panels

8. Windmill

9. Low-energy computers

Typical Energy Saving Approach in Buildings:

• Minimize exposure on the south and west
• Use simulation tools and techniques which can help in designing the orientation to minimize heat ingress and enhance energy efficiency.

Equipment & systems:

• Select chillers with high Coefficient of Performance (CoP).
• Install Variable Frequency Drives (VFD) for supply &return air fans and pumps.
• Select high efficiency cooling towers.
• Use high-efficiency motors, transformers and pumps.
• Install Heat recovery wheels and economizers.
• Consider night purging with ambient air to flush out the heat trapped within the building during the day.
• Adopt Controls & Building Management Systems for effective control.
• Engage a Commissioning Authority to ensure that savings are realized once the building becomes operational.

Lighting:

• Design in such a way that the building gets maximum daylighting.
• Overall lighting power density can be designed as less as 1.0 W/sq.ft.
• Use daylight-cum-dimmer controls
• Install occupancy sensors
• Select energy-efficient luminaries like CFL, T-5, LED, etc.

Water Efficiency:

Design for dual plumbing to use recycled water for toilet flushing or a greywater system that recovers rainwater or other nonpotable water for site irrigation.

Minimize wastewater by using ultra low-flush toilets, low-flow showerheads, and other water-conserving fixtures.

Use recirculation systems for centralized hot water distribution.

Install point-of-use hot water heating systems for more distant locations.

Use a water budget approach that schedules irrigation using the California Irrigation Management Information System data for landscaping.

Meter the landscape separately from buildings. Use micro-irrigation (which excludes sprinklers and high-pressure sprayers) to supply water in non-turf areas.

Use state-of-the-art irrigation controllers and self-closing nozzles on hoses.

Building Operation and Maintenance:

Green building measures cannot achieve their goals unless they work as intended. Building commissioning includes testing and adjusting the mechanical, electrical, and plumbing systems to ensure that all equipment meets design criteria. It also includes instructing the staff on the operation and maintenance of equipment.

Over time, building performance can be assured through measurement, adjustment, and upgrading. Proper maintenance ensures that a building continues to perform as designed and commissioned.

A Civil Engineer's Role in Green Rating Systems

A half-dozen or more "green" rating systems are available, each with a different set of guidelines and focus.  The civil engineer plays a role in all of these systems, but the level of involvement and opportunity can differ significantly.  Most of the systems focus on green buildings, but there is also a system focusing on sustainable sites and a new green rating system focusing on roads.  Unfortunately, civil engineers have taken a back seat to architects and other engineers in the green building process and don't contribute as much to the process as they could.  That needs to change.  The future of the market is in sustainable design, and a civil engineer's familiarity with and ability to work within these green rating systems is vital to long-term success.  The number of rating systems is too long to list and describe in this post, but the systems below are some of the more well-known and pertinent for the civil engineering profession.

1. LEED - The Leadership in Energy and Environmental Design (LEED) Green Building Rating System is the most widely-recognised system for measuring green construction projects. The rating systems have grown to include over six different project types, including New Construction (with speciality areas including schools, healthcare and retail), Existing Buildings, Commercial Interiors, Core and Shell, Homes and Neighborhood Development.  These systems allow the civil engineer to be involved with about 20% of the total available points in each system assigned to the site.  By becoming familiar with the entire rating system, not just the site credits, the civil engineer can add value by understanding the potential synergies among different point categories and contribute to an integrated design approach.    
2. The Living Building Challenge - The Living Building Challenge was developed by the Cascadia Region Green Building Council.  In the words of the International Living Building Institute, the Living Building Challenge "...defines the most advanced measure of sustainability in the built environment possible today and acts to diminish the gap between current limits and ideal solutions."  The Living Building Challenge applies to all project types and sizes and is extremely environmentally rigorous. More than any other system it stresses the synergies between the different disciplines and functions of the built environment and how it interacts with the environment and society.  There are opportunities and requirements for civil engineering involvement within this system, and as with LEED, the ability to create synergies between disciplines and areas is extremely important.  
3. Sustainable Sites Initiative - The Sustainable Sites Initiative (SITES) was developed as an interdisciplinary effort between the American Society of Landscape Architects (ASLA), the Lady Bird Johnson Wildflower Center and the United States Botanical Garden.  SITES was created to promote sustainable land development and management practices and was the first rating system to apply to sites with or without buildings.  The SITES system has five focus areas: hydrology, soils, vegetation, materials and human health and well-being.  Civil engineers have a great opportunity with this system to lead landscape architects in creating sustainable projects.                                                   
4. Greenroads  - The Greenroads Sustainability Performance Metric is a brand-new roadway design and construction rating system.  The system is a joint effort of The University of Washington and CH2MHILL.  It applies to new and reconstructed/rehabilitated roads and awards certification at four levels: certified, silver, gold and evergreen.  Greenroads focuses on creating roadways with less environmental impact, lower lifecycle costs and more positive societal outcomes.  The rating system is based on sustainable best management practices and choices backed by empirical evidence and sound engineering.  Greenroads is the first and only widespread rating system based solely on engineering practices.  Possibly even more so than the Sustainable Sites Initiative, Greenroads allows civil engineers to be in the driver's seat in creating more sustainable projects.  

This list certainly does not include all of the green rating systems currently available or in development, but it does provide a representative list.  All of the above rating systems provide a substantial  framework for projects that are better for the environment, society and long-term financial sustainability even if certification is not pursued. Now and shortly both public and private clients are going to demand sustainable designs for their projects, and many are going to ask for certification under one of the green ratings systems.  The sooner that civil engineers become familiar and comfortable with these systems, the more prepared they will be when the time comes to contribute to a green project.

Posted by Bob