Transcript Lean Construction

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Sustainable Design and Built Environment
By: Engr. Dr. Attaullah Shah
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Sustainable design
Islamic teachings and Environment
− We made from water everything living (Quran 21:30)
− Have We not made the earth sustainable (receptacle, have a self
sufficiency), For the living and the dead. (Quran.77/ 25-26)
− “And the earth We have spread out (Like a carpet); set thereon
Mountains firm and immovable; And produced therein all kinds of
things in due balance. And We have provided therein Means of
subsistence,—for you And for whose sustenance Ye are not
responsible.” (15:19-20)
− “It is He who produceth Gardens, with trellises And without, and
dates, And tilth with produce Of all kinds, and olives And
pomegranates, Similar (in kind) And different (in variety): Eat of
their fruit In their season, but render The dues that are proper On
the day that the harvest Is gathered. But waste not By excess: for
God Loveth not the wasters.” (6:141)
− "If any Muslim plants any plant and a human being or an animal
eats of it, he will be rewarded as if he had given that much in
charity." (Sahih Al-Bukhari, 8:41)
− The Prophet, peace be upon him, said: “And to remove a harmful
thing from the way is also sadaqah (a charity).” (Al-Bukhari and
Muslim.)
− "If the Hour is about to take place while any one of you has a sapling
in his hand, which he can cultivate before it takes place, let him
cultivate it for he will be rewarded for it.“( Prophet PBUH)
− The Prophet (peace and blessings be upon him) says: "Allah is
beautiful and He loves the beautiful."
− Allah’s Messenger said the right of the road is Lowering your gaze,
returning greetings, and removing harmful things from the road”
(Reported by Muslim).
Layout of presentation
− Sustainability-Definitions
− New Technologies and Sustainability
− Principles of Sustainable design in built environment
− Lean Construction principles
Sustainability
Sustainable development generally thought of as:
− "development that meets the needs of the present without
compromising the ability of future generations to meet their own
needs."
definition developed by the Bruntland Commission in 1987
Another concept, thought to be more solutions-oriented,
more inspirational:
− “Sustainable development is a very simple idea. It is about
ensuring a better quality of life for everyone, now and for
generations to come.”
− Proctor & Gamble
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Sustainability
− The dimensions of sustainability are not independent of
one another, but instead intertwine in the tradeoffs that are
inherent in any engineering decision.
− Interrelationships among dimensions create the complexity
inherent in sustainable engineering design and decision
making.
− Perfect sustainability for the earth system is (theoretically)
possible
− as long as the inhabitants of Earth consume less energy than
supplied by the solar energy budget as long as the sun continues
to shine.
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Sustainability and Technology
− Technology plays a very important role in sustainable development
because it is one of the most significant ways in which we interact with
our environment
− Technologies are used:
− To extract natural resources
− To modify them for human purposes
− To adapt our man-made living space
− Technology has created engineered systems that have given us drastic
improvements in the immediate quality of life of many people
− Many of these short term improvements in the immediate quality of life
have also extracted a great toll on the environment
− We need to develop and use technologies with sustainability in mind:
"sustainable technologies“
− Sustainable technology
− one that promotes a societal move toward sustainability
− A technology that fits well with the goals of sustainable development
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Sustainability and Technology
− Sustainable technologies must have the
following characteristics (in addition to
meeting traditional engineering requirements
and constraints):
− Minimize use of nonrenewable energy and natural
resources
− Satisfy human needs and aspirations with
sensitivity to cultural context
− Have minimal negative impact on the earth's
ecosystems
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Sustainable Built Environment
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Impact of building on the Environment
Law of Resource Conservation
Three basic Principles of Sustainable
Building Design
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Resource Conservation.
− Energy Conservation
− Water Conservation
− Material Conservation
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Life Cycle Costing
− Pre- Building Phase
− Building phase
− Post Building Phase.
3. Humane Design
− Preservation of Natural conditions
− Urban Design site Planning
− Design for humane comfort
Future sustainable buildings
Principle No1: Economy of Resources
− Energy Conservation:
− Maximize the use of natural resources on the site.
− In temperate climates, open southern exposure will encourage
passive solar heating;
− Deciduous trees provide shade in summer and solar heat gain in
winter.
− Evergreens planted on the north of a building will protect it from
winter winds, improving its energy efficiency.
− Buildings can be located relative to water onsite to provide
natural cooling in summer.
− Energy-conscious Site planning:
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Passive solar architecture
Shading in summer, by plants or overhangs
The wind, or the flow of air: cooling and hygienic effects.
High-performance windows and wall insulation
Reduced heating and cooling loads require smaller HVAC equip.
− Alternative sources of energy
− Solar, wind, water, and geothermal energy systems are all
commercially available to reduce or eliminate the need for external
energy sources.
− Electrical and heating requirements can be met by these systems, or
combination of systems, in all climates.
− Day lighting:
− Building and window design that utilizes natural light.
− Lead to conserving electrical lighting energy,
− Shaving peak electric loads, and reducing cooling energy
consumptions.
− Day lighting increases the luminous quality of indoor
environments,
− Enhancing the psychological well-being and productivity of
indoor occupants.
− These qualitative benefits of day lighting can be far more
significant than its energy-savings potential.
Passive Solar House design
− Energy-Efficient Equipment & Appliances
− Careful selection of high-efficiency heating, cooling, and ventilation
systems
− The initial price of this equipment may be higher than that of less
efficient equipment, but this will be offset by future savings.
− Choose Materials with Low Embodied Energy:
− The embodied energy of a material attempts to measure the energy that
goes into the entire lifecycle of building material.
− For instance, aluminum has a very high embodied energy because of the
large amount of electricity that must be used to manufacture it from
mined bauxite ore; recycled aluminum requires far less energy to refabricate. By choosing materials with low embodied energy, the overall
environmental impact of a building is reduced.
− Using local materials over imported materials of the same type will save
transportation energy.
Sustainable Building Design
Future Solar Energy Houses
− Water Conservation:
Water consumed in buildings can be classified as two types:
Gray water Can be easily re-cycled
Sewage- Need treatment plant
Reuse:
- Rainwater collection
-Gray water collection
Reduction:
-Indigenous landscaping — using plants native to the local ecosystem —
will also reduce water consumption.
-These plants will have adapted to the local rainfall levels,
-The sprinkler heads should be carefully placed and adjusted to avoid
watering the sidewalk and street.
-Low-flow showerheads.
-- Vacuum-assist toilets or smaller toilet tanks
Grey water Reuse system
− Material Conservation:
- Material conserving design and construction
- Proper sizing of building systems
- Rehabilitation of existing structures
- Use of reclaimed or recycled materials and components
- Use of non-conventional building materials
Design of a Stadium
Material Conservation
− Adapt Existing Buildings to New Uses
− One of the most straightforward and effective methods for material
conservation is to make use of the resources that already exist in the
form of buildings.
− Incorporate Reclaimed or Recycled Materials
− Buildings that have to be demolished should become the resources for
new buildings. Many building materials, such as wood, steel, and glass,
are easily recycled into new materials.
− Use Materials That Can Be Recycled
− During the process of designing the building and selecting the building
materials, look for ways to use materials that can themselves be
recycled. This preserves the energy embodied in their manufacture.
− Size Buildings and Systems Properly.
− A building that is oversized for its designed purpose, or has oversized
systems, will excessively consume materials.
Principle 2: Life Cycle Design
Pre-building Phase.
− Use Materials Made From Renewable Resources.
− Use Materials Harvested or Extracted Without Causing Ecological
Damage
− Of the renewable materials available, not all can be obtained without
significant environmental effects. Therefore, the architect must be aware
of how various raw materials are harvested and understand the local
and global ramifications.
− Use Recycled Materials
− Using recycle materials reduces waste and saves scarce land-fill space.
Recycled materials also preserve the embodied energy of their original
form, which would otherwise be wasted.
− Use Materials with Long Life and Low Maintenance
− Durable materials last longer and require less maintenance with harsh
cleansers.
Building phase
− Minimize Site Impact
− Careful planning can minimize invasion of heavy equipment and the
accompanying ecosystem damage to the site.
− Excavations should not alter the flow of groundwater through the site
− Finished structures should respect site topology and existing drainage.
− Trees and vegetation should only be removed when absolutely
necessary for access
− Employ Nontoxic Materials
The use of nontoxic materials is vital to the health of the building’s
occupants, who typically spend more than three-quarters of their time
indoors.
Post Building Phase:
− Reuse the Building.
− The embodied energy of a building is considerable. It includes not only the
sum of energy embodied in the materials, but also the energy that went into
the building’s construction.
− Where complete reuse of a building is not possible, individual components
can be selected for reuse — windows, doors, bricks, and interior fixtures
are all excellent candidates.
− Recycle Materials
− Recycling materials from a building can often be difficult due to the difficulty
in separating different substances from one another.
− Some materials, like glass and aluminum, must be scavenged from the
building by hand.
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Reuse Existing Buildings and Infrastructure
− Adoptive Re-use
Green Architecture and Building Design
Principle 3: Humane Design
Preservation of Natural Conditions
− Respect Topographical Contours:
− The existing contours of a site should be respected.
− Radical terra forming is not only expensive but devastating to the site’s
microclimate.
− Alteration of contours will affect how water drains and how wind moves
through a site.
− Do Not Disturb the Water Table
− Select sites and building designs that do not require excavation below the local
water table.
− Placing a large obstruction (the building) into the water table will disturb natural
hydraulic process.
− If the water table is exposed during construction, it will also become more
susceptible to contamination from polluted surface runoff.
− Preserve Existing Flora and Fauna
− Local wildlife and vegetation should be recognized as part of the building site.
− Native plants and animals will make the finished building a more enjoyable
space for human habitation.
Urban Design and Site Planning
− Integrate Design with Public Transportation
− Sustainable architecture on an urban scale must be designed to
promote public transportation. Thousands of individual vehicles moving
in and out of area with the daily commute create smog, congest traffic,
and require parking spaces.
− Promote Mixed Use Development
− Sustainable development encourages the mixing of residential,
commercial, office and retail space.
− People then have the option of living near where they work and shop.
This provides a greater sense of community than conventional
suburbs. The potential for 24-hour activity also makes an area safer.
Green Housing
Design for Human Comfort
− Provide Thermal, Visual, and Acoustic Comfort
− People do not perform well in spaces that are too hot or too cold.
− Proper lighting, appropriate to each task, is essential.
− Background noise from equipment or people can be distracting and
damage occupants’ hearing.
− Acoustic and visual privacy also need to be considered.
- Provide Visual Connection to Exterior
− The light in the sky changes throughout the day, as the sun and clouds
move across the sky.
− Humans all have an internal clock that is synchronized to the cycle of day
and night.
− From a psychological and physiological standpoint, windows and skylights
are essential means of keeping the body clock working properly.
− Provide Operable Windows
− Operable windows are necessary so that building occupants can have some
degree of control over the temperature and ventilation in their workspace.
− Provide Fresh Clean Air. Fresh air through clean air ducts is vital to the wellbeing of building occupants. The benefits of fresh air go beyond the need
for oxygen. Continuous recirculation of interior air exposes people to
concentrated levels of bacteria and chemicals within the building.
− Use Nontoxic, Non-Out gassing Materials
− Long-term exposure to chemicals commonly used in building materials and
cleaners can have a detrimental effect on health.
− Accommodate Persons with Differing Physical Abilities
− One aspect of sustainable design is its longevity.
− Buildings that are durable and adaptable are more sustainable than those
that are not. This adaptability includes welcoming people of different ages
and physical conditions.
− The more people that can use a building, the longer the building successful
life.
My Environment Friendly House
Example of Eco Friendly Design
EPA Research Triangle Park
Campus USA
EPA Research Triangle Park Campus USA
During construction, 80% of the construction waste was segregated and
recycled - keeping about 20 million pounds of materials out of regional
landfills. By using an on-site concrete batch plant, EPA eliminated at least
75,000 highway miles of concrete truck traffic and avoided the combustion
of at more than 10,000 gallons of fuel. Having the plant at the site also
enabled wastes like crushed scrap concrete to be directly reused for the
project.
A few more of our green construction practices include:
- No on-site burning
- Aggressive forest protection
- Stringent protection for lakes and streams
- Landscaping debris ground and used on-site as mulch
- Gypsum trimmings recycled or applied as soil amendments Reflective,
white roofing was also used to limit heat absorption. The white roof and
light-colored exterior walls increase the building's albedo, significantly
lowering air conditioning costs. In addition to these architectural features,
trees surrounding the building were left in place to help shade.
Computer Centre EPA –USA
Computer Centre
Labs
Lake
Welcome
Transport
High Bay
Building Exterior
Green Roofs
Exterior
Atrium
Indoor Environment
Offices
Building amenities
Lean Construction Principles
The lean principles
− Eliminate waste
− Precisely specify value, from customer viewpoint
− Identify value-stream, eliminate non-value adding steps
− Improve value process flows
− Respond to customer requirements
− “Customer pull”
− “Just–in-time”, “right first time”
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What wastes are involved?
− Complexity - Complex products harder to manufacture, produce more
waste
− Labour - Improve assembly line-type techniques
− Overproduction - Produce exactly what is wanted, when it is wanted
− Space - Plan efficient use of buildings, plant areas, circulation space,
both in factory environment, and on project sites, & buildings
− Energy – reduce excess power utilisation, unproductive operations
− Defects – no mistakes, rework, defects, in factory or on site
− Materials – avoid scrap, trim, excess or bad materials, excess stocks
− Time – downtime, unnecessary delays of people or machines
− Transport – eliminate unnecessary movements in factory & on-site, no
double-handling
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Lean thinking in Construction
− All the previous ideas can be relevant to the
construction process…
− Design
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Virtual Reality, 3d CAD
Customer can “walk through” a building at design stage
Use standardisation, pre-assembly techniques
Design & build contracts
− Production Planning
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Benchmarking to find “best in class”
Clear, stable project programmes
Critical path analysis
Risk management
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Lean Construction
Lean Construction is a term which comes from
“Lean thinking”, a philosophy, derived from “lean
manufacturing” techniques
− Lean manufacturing pioneered by Toyota
− It is all about elimination of “muda” – waste
− Covers all activities & process which consume resources,
but do not add value to the product
− Focuses on customer needs
− Lean Construction is a therefore a production management
approach to project delivery – a new way to design and build
capital facilities
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Lean Construction
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Project plans, systems approach
Defined construction methods
Agreed by all parties
Communicated to all interested parties
Revisions minimised, kept up-to date
Train the workforce
− “tool-box talks”, Health & safety
− Multi-skilling, flexibility
− Progress reports
− Commitment to improve
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Related areas to Lean Construction
Lean thinking and lean construction lead to use of
standardised products, and pre-assembly
techniques
Standardisation-“Extensive use of components,
methods or processes in which there is regularity,
repetition, and a background of successful practice”
− WHY does Construction industry need it?
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Too many unique components products
Lack of thorough design
Not enough testing
Customer requires better guarantees of serviceability
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Benefits of Standardisation
− Improved predictability
− Shorter lead times
− Improved product reliability
− Improved quality
− Lower costs
− Reduced waste – scope for re-cycling
− Ease of maintenance
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Different types of standardisation
− Generic
− Is by nature standard, - steel concrete plaster
− Is ISO certified, etc
− National
− National standards for brick sizes, etc
− Client
− Client wants the same product throughout its business
− Tesco, Body Shop, McDonalds, etc
− Supplier
− Standard product ranges & sizes for components
− Project
− Design team decisions re dimension grids, modules, etc
Bernard Potter
School of the Environment
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Modularisation or Volumetric
pre-assembly
− NOTE : There is often confusion about these terms,
some magazines refer to them as being the same.
− Volumetric Pre-assembly
− Complete fitted out unit, eg kitchen or bathroom, lift shafts
assembled before being placed in final position
− Often produced under factory conditions
− Modular buildings
− Whole building consists of modular units
− Hotels, schools, army barracks
Bernard Potter
School of the Environment
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Supply chain management
− Lean manufacturing requires new attitudes & input from
suppliers, closer relationships
− Cooperation & planning
− Partnering, shared business strategies
− Open-book accounting
− Performance standards
− Continuous improvement
− Networking
Bernard Potter
School of the Environment
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Partnering is………..
− Partnering is a new philosophy of parties working together, who might
previously had a more antagonistic relationship
− Is a “win-win” relationship
− Has become important way in which contractors SELL and clients
PROCURE construction services
− Partnering is a strategy to increase repeat business
− Partnering can be a means of increasing levels of client satisfaction
− Can provide a more stable workload
− Partnering is NOT a contract form
Bernard Potter
School of the Environment
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Wider implications of partnering
− Partnering is not just a concept for contractors and
clients, or a narrow view of procurement
− What about suppliers & manufacturers?
− “The supply chain”
− Managing the supply chain requires commitment by
many different parties with common interests
− Concept of “Lean production”
− “Just in time”, “right first time”
− Egan’s views on learning from other industries
Bernard Potter
School of the Environment
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Conclusion
− Sustainable development is the need of the day.
− The resource conservation, reducing life cycle costing and
enhancing the user’s comfort in the design of built
environment can lead to pollution free and sustainable
design and construction
− Lean Construction is an endeavor to save the natural
resources in the design, construction operation and
maintenance of built facilities. This in turn leads to
sustainability in construction.