Construction Method Materials 2013
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Transcript of Construction Method Materials 2013
EMSC 5103 : Sustainable Construction - Design, method and materials
Sustainable construction
Sustainable construction is defined as “the creation and responsible management of a healthy built environment based on resource efficient and ecological principles” (Yeang, 1995)
Resource base Where is it from? – renewable materials? From fragile location? limited supply?
Embodied pollution activities that produced wastes eg from: extraction, processing and production ; type of wastes; recycled materials? transportation i.e too far? Distribution too far? Too much packaging?
Impact in use Detailing of the building for EE etc, toxicity of materials – paints, varnishes, formaldehyde in plywood, chipboard, foam; vinyl products eg flooring tiles; timber treatment.Passive environmental control eg moisture and thermal by design,
Final destination Reduce consumption rate in order to reduce waste productionDurability – quality of materialsMaintenance – maintenance-free building Life spans - 100 years? 50 years? element of service 10 years?
What can we do 5 R – refuse to use, reduce, reuse, recycle and repair
Five principles of Environment architecture
EMSC 5103 : Sustainable Construction -
Healthy interior environment
All possible means are taken to ensure materials and buildings systems do not emit toxic substance and gases into the interior atmosphere
Energy efficiency All possible means are taken to ensure the building uses minimum energy
Ecological kind materials
Building materials are from source that minimize destruction of global environment
Environmental forms
•All possible means are taken to relate the form and plan of the design to local site, region and climate. The form of buildings to be to a harmonious relationship between the inhabitants and nature
Good design Aim to have efficient, long lasting and elegant relationship of used areas, circulation, building form, mechanical systems an construction technology
EMSC 5103 : Sustainable Construction - Efficiency in sustainable design
energy efficiency
Energy use of a building is probably the single greatest environmental impact of a building. Decision made during the design and construction of a building will go on affecting the environmental performance of that building for decades to come. Renewable energy source is encouraged. Utilizing natural lighting and ventilation is another option
Water efficiency
Water is another important element in building either during the construction or during occupancy. Excess water usage will increase the production of wastewater which require more energy to treat. Recycling of grey water can reduce water demand for toilet flushing.
Materials efficiency
No matter what the materials, using less is always preferable as long as the durability or structural integrity of a building is not compromise.
Waste efficiency
Reduce waste production
4 R of sustainable design
EMSC 5103 : Sustainable Construction -
reduce Design for lower quantity of materials, resources and embodied energy. Select durable and expected to perform well over the service years.
Reuse “effective way to avoid further withdrawal of natural resources and creation of environmental pollution associated with then extraction, trans[ort, processing, manufacturing. Installation and disposal of the used materials.” in terms of materials and also building. Reusing old buildings by changing its function.
Recycle Emphasize on the use of recycled materials and designing a home with recycling capability. It will avoid on using virgin materials
Renewable Utilization of renewable energy from natural sources such As wind, solar heat etc. Will discuss on RE in later chapter
Stages EMSC 5103 : Sustainable Construction -
Sustainable construction
The elements of sustainable construction
Planning To include sustainable aspiration
Design Design to have sustainble approach in every sense 1. Setting the aspiration2. Protecting aspiration 3. Production information and tender
Pre- project execution
4. Tender action 5. Mobilisation of the project
Construction process
6. Construction to practical completion •Main site issues
Handling over 7. After practical completion •Provide training and detail post management •Operation and maintenance •Monitoring
Post occupant evaluation
•Feedback•POE,
EMSC 5103 : Sustainable Construction - Design consideration
Site consideration
The site and its buildings are interrelated with their surroundings. They are not only related to the aesthetic aspect but more specifically to the local climate, landscape features and neighboring buildings that might create variations to the microclimate.
Wind Wind provide natural ventilation. The design should reflect the wind direction and how it is channeled over the site in a away that the building catches the wind and utilized the pressure to ventilate the internal space. • Promote direct flow direction.Ventilation is necessary to provide oxygen and to remove contaminated air as human body required a constant supply of oxygen .
Water Conserve the use of fresh and treated water
Sun and natural
sunlight
•Daylight usually admitted into building through windows or skylights but they might also transmit heat, sound and air through them also. •A rectangular building in a tropical should be located with its longest axis in an east to west direction in order to avoid direct sun light
Existing landscape
•Existing landscape is refereeing to natural features such as trees, slopes and peaks as well as surrounding artificial features such as buildings. Need to consider how the building affects and being affected by the local climate. •Plants adsorb CO2 and visual screens and sound diffusers to reduce sound and air pollution. Plants also serve as windbreakers and provide low-shields to the buildings
EMSC 5103 : Sustainable Construction - Construction process
The key issues that require attention in relation to the process of sustainable construction are
1) The delivery of the aspirations for a building from inception to handover and beyond such that it can meet the increasingly common social expectation
2) The construction process itself. – to ensure that the methods of building and impact of construction on community and environment is as ‘kind’ as possible
3) The process of feedback so that experiences can be shared and continue for continual improvement
There is lack of information regarding sustainable construction in Malaysia. The construction industries need to compile and compel those embark on sustainable construction in Malaysia to share their experiences, challenges and problem solving.
Sustainability baton
The sustainability aspiration normally is high at briefing. But at each stage of procurement , the “baton’ being drop or challenge throughout the process and particularly as responsibilities transfer from the client to design team to the contractor and back to the clients . What can we do to sustain that ‘baton’?? Need strong support and high inspiration.
Six attributes that are vital for sustainable construction
1 Stewardship/ownership of project is a vital aspect in delivering sustainable project. Failure to indentify appropriate targets, tools and benchmarking or to look to long-term manageability poses serious challenge.
2 Getting support communities – identify and meet the real needs requirements and aspirations of communities and stakeholders and involve them in key decisions
3 Enhance biodiversity – do not use materials that threatened species and environments and improve natural habitat where appropriate
4 Create healthy environments – enhance living, leisure and work environments; do not endanger the health of workers, users via exposure to pollutants
5 Use resource effectively – do not consume disproportionate amount of resources including money, water, energy, materials, lands during construction and handing over. Do not generate unnecessary wastage due to short life, poor design, inefficiency or less than ideal construction
6 Minimize pollution – create minimum dependence on polluting materials,
What can we do to obtain that sustainability aspiration? – the stages in sustainable construction project planning
1 Setting the aspirations:•Prepare a sustainable policy statement i.e protection of environment and reduce wastage•Adopt life cycle approach and costing•Set targets for energy and water consumption seek the best possible guidance on sustainability issue•Avoid gimmick and over sizing, •Think through building control; and management and strategies how to obtain feedback•Consultation with stakeholders – get them involved and get their feedbacks
Community consultation can enhance a project by •Providing the opportunity for a community to broaden its horizon and hand-on experience•Brining people together •Providing a community sense of ownership
What can we do to obtain that sustainability aspiration?
2 Protecting the aspiration:•The design team requires to see all aspect of construction through the “sustainable” criteria filter – money, materials, lighting, control, landscape, fabric, form, orientation, energy, fire protection, heating, waste. IT, ventilation, cooling, transport, water provision, coordination, changing legislation, policy, and building management. all the design team will be required to negotiate and agree to resolve cross cutting issues. •It is important to benchmark the performance, labelling of materials and products, building and process need to be agreed.
3. Production information and tender stage It is important to make sustainability aspects as contractual. •Ensure contractors understand the issues and potential benefits on sustainability construction•Provide adequate information in “prelims” to avoid substitution without approval•Encourage the contractors to join “Considerate Constructors scheme” and to set a clear target and record achievements under CEEQUAL or BREEAM assessment,
EMSC 5103 : Sustainable Construction -
Considerate contractors’ scheme
It is voluntarily Code of Practice open to all contruction companies: it seeks to:1. Minimize the disturbance or negative impact sometime caused by
construction sites to the immediate neighbor2. Eradicate offensive behaviour and language from construction
sites3. Recognize and reward a contractor’s commitment to raise
standard of site management, safety and environmental awareness beyond statutory duties
Civil Engineering environmental quality assessment Scheme CEEQUAL
It aims to encourage the attainment of environmental excellence in civil engineering projects. It focuses on the processes that enable delivery of best practice and is robust enough to deal with projects of long timescale.
Contractor benefits of SC:
Reducing waste, saves moneyLess time in repairing enviornmental damageReduce risk of legal costs(fines)Better company profileImprove tender opportunitiesReduced neighbor disputesReduced demand for resources
What can we do to obtain that sustainability aspiration?
4 Tender Action stage There are various way in which the sustainability agenda can be at risk•The bill and specification are not clear•The subcontractors do not pick up “novel” specification and/or ignore the price implications of novel specification•Failure to identify important/specific supplier•Tender too high (fear of unknown)
Hence it is useful – to have a period of information exchange prior to the tendering process. Allow bidding contractors to attend and queries on the key sustainable aspect of project,.
5 Mobilization stage It is important to make sustainability aspects to be contractual. •Ensure that environmental statement of the finished building should be established.•Methods statements, targets, and information on environmental issues should be established with subcontractors. •Any specialist materials should be highlighted and supply chain issues identified
What can we do to obtain that sustainability aspiration?
6 Construction to almost completion stage Much is to be gained or lost during the period of delivery of the building itself. Establishing controls within the routine of the site operation will be beneficial. •Unique or unusual elements, materials, products or services system should be explained even to the new workers•All relevant subcontractors should have explanations of key environmental elements
•Checking to make sure the products are of the required quality and that they work as specified and operate according to the manufacturer's recommendation
•At the handover stage, the client need the support to be able to use the building appropriately . Hence training is needed for all by the design team and specialist technology/materials installers.
•Once the building is under operation, it is beneficial for design team to maintain direct interest on the building in order to obtain feedback from the clients
•Best practice examples show that significant savings on energy and maintenance costs can be achieved through effective feedback
What can we do to obtain that sustainability aspiration?
7 After practical completion A lack of understanding on controls, design parameters can reduce the sustainable building efficiency . “sustainability is a process and not a product (life long learning process)”
The test of a “sustainable building” is when the clients/user take over and operate the building.
Achievement of a sustainable aspiration is a complex interaction of design, designed manageability, client commitment and user understanding.
Monitoring is essential – there is significant benefits in monitoring key aspects of a building’s resource usage (i.e water, energy, waste materials etc).
What can we do to obtain that sustainability aspiration?
7 Post occupancy evaluation POE –
Post occupancy evaluation POE – or post occupation studies ought to cover all aspects of building performance – space, cost, aesthetic, operations, use, occupation satisfaction, management, environmental performance etc. they should consider the way the building was procured, briefed, designed and occupied. PROBE = post occupancy evaluation of buildings and their engineering aspects.
POE can help to iron out common problems in buildings, such as lights on unnecessarily and windows propped open against design intent . If it is detected n the early stages- it can save money and increasing comfort and satisfaction .
Challenges in POE execution: •Too many methods available for POE implementation. •Costs – difficult to obtain•Aesthetic – subjective •Space efficiency, density or utilization which is easily carried out but rarely asked•Design and procurement history which is often quite hard and expensive to study as the design team most probably had dispersed.
What can we do to obtain that sustainability aspiration?
7 PROBE = post occupancy evaluation of buildings and their engineering aspects. It measures : •Energy - the energy assessment and reporting methodology EARM comprehensively covers building energy performance from both supply and demand perspective, which helps in a thorough understanding of technical performance and is helpful with diagnostic
•Occupants – using perceived ratings and attitudinal observations from questionnaires followed up with interview and discussion if necessary . Building use studies BUS occupants questionnaires covers occupants issue like comfort, health and productivity in a format which give a useful across wide range of discipline eg architecture, building services, facilities management.
•Air tightness – an air pressure test examines the airtighness of the fabric presumably for containment of air for thermal comfort.
•Pre-visit questionnaires to collect basic data about hours of use, plans and other background information•A water consumption method •A supplementary questionnaires on journey to work and transport mode.
The barriers of implementing PROBE 1. Occupied buildings are complex system that are challenge to study – to decide
which element to study.
2 POE study are often enthusiastically supported by lower level in a organization but vetoed by higher management – “secret” data
3 POE by their nature are multi discipline. They have to deal with topics from supply industry’s perspective and from user side.
4 The industry is not organized to collect POE and feedbacks information and deal with it. see as threat.
5 Clients do not see why they should be doing something they hope to take for granted
6 Academic do not regard building performance as an area of legitimate interest.
7 Secrecy – no communication between the manager of the building and supplier
8 Professionals tend to be territorial and not willing to know/listen user perspective
9 One needs lot of knowledge before proceed to do POE i.e not many trained to do so
10 Most designers go straight to next job without learning from the one just completed might be due to time/cost.
What can we do to obtain that sustainability aspiration?
7 Example of PROBE, D:\OUM master class\4_1_Kolokotroni Post Occupancy Evaluation of Buildings.pdfD:\OUM master class\energy-assessment-methodology.pdfD:\OUM master class\poe survey2.pdfD:\OUM master class\Keynote Lecture 3 - Low Carbon Cities & Sustainability.pdfD:\OUM master class\BR12 probe.pdf
EMSC 5103 : Sustainable Construction Materials selection - Some of the common materials use at construction are known to be toxic Alternative materials
1) Polyvinyl chloride PVC
Risks:•During manufacturing, ingredients such as vinyl chloride monomer emit dioxin and others.•During use – PVC products leach toxic additives,•Disposal – leaches toxic additives when disposed at landfill and release dioxin when incinerated
Possible PVC alterative •Stainless steel conduit/pipes•Use polyethylene (PE), polypropylene (PP), or rubber sheathing for wiring•Copper or PE water pipes•Cast iron rainwater containers•Linoleum or rubber instead of vinyl floor coverings
2) Formaldehyde
Used in manufacturing process such as paints, plastic products, paper, textiles, carpets, pesticides, and fumigants, chipboards and plywood , thermal insulation, furniture, adhesives , glues and resins•Risks: long term exposure may cause cancer. It is asthma trigger
•Cellulose insulation•Water based paint •Natural timber in lieu of chipboard etc
EMSC 5103 : Sustainable Construction Materials selection - Some of the common materials use at construction are known to be toxic Alternative materials
3) solvents
Risks: Range from irritation and headsche to dermatitis (skin problem) colour blindness, brain damage, cancer
•Natural water based emulsion paints•Linseed oil based gloss paint•Avoidance materials that required or containing glue•Where use of glue is unavoidable, use solvent/formaldehyde free glues•Avaoidance of timber treatemtn through detailing
EMSC 5103 : Sustainable Construction
Some of key site issues 1. Wild life Action must be taken to minimize damage to the site ecology
(ideally). All site actions are potential threats because of :•Changes to water quality •Destruction of habitats•Damage to vegetation•Interruption to wildlife movements•Dust, noise and lighting pollution•Damage, removal or burial of rock formations
2. Contamination Main example of contamination risks are•Contamination encountered during works•Handling/excavating contaminated ground and polluting aquifer •Windblown dusts•Stockpiling contaminated materials that leaches•Spillage of contaminants' eg oils•Discharge of contaminated de-watering
EMSC 5103 : Sustainable Construction Some key site issues
3. Waste The issues are: monitoring procedures, raw materials wastage, storage and handling, reduction of landfill tax, potential for reuse and recycling, transport and disposal. Need to consider issues:•Legislation and penalties•The nature of any potential damage to the environment•Potential impact on project/budget
4. Emissions Site dust, emissiojns and odour cause annoyance and health risks.•Use containment method fpr demolition•Keep plant clean•Keep earthwork damp amd revegetate•Clean concrete pour-and-batching regime•Minimise site cutting, grouting and grinding•No burning on site
EMSC 5103 : Sustainable Construction Some of key site issues
5. Water Relevant issues within water strategy are•Water abstraction•Water disposal•Spillage•Vehicle washing effluent•Surface water runoff•Silty water•Pumping to grassland•Settlement tanks•Lagoons, sewage discharge
6. Noise •Evaluate potential noise/vibration problems and monitor levels before starting•Inform neighbours•Minimise and monitor effects during work•Monitor conditions after works are complete
7. Archeology •Archeological sites are irreplaceable and early investigation is essential if significant delay and costs are to be abvoided/
EMSC 5103 : Sustainable Construction
Green materials Definition of green materials
Green building materials are those that use earth resources in an environmentally responsible way and respect the nature cycles and interrelationship with ecosystem•Non toxic•Made from recycled materials and themselves are recyclable •They are energy efficient and water efficient•They are green the way they are extracted, manufactured, the way they are used, and reclaimed after used.•Has high mark for resource management, impact on indoor environmental quality and performance.
Resources management
The impact of products on the earth resources, Its impact on biodiversity and ecosystemIts favours: reduce, reuse, recycle and renew
Non sustainable resource management causes:•Pollution to water, air •Depletion of raw materials•Destruction of ecosystem during acquisition of raw materials
EMSC 5103 : Sustainable Construction
Green materials Why use green materials?
•Can help to divert indoor air quality liability claims, “sick building syndrome ”according to US NIOSH, the relative causes of poor indoor air quality : inadequate ventilation; indoor contaminants; outdoor contaminants . •Respond to consumer demand – healthy building and energy efficiency structures •Economic benefits – reduce claim from sick building, cheaper to manage than to clean up wastes, •Provide compliance with certain regulatory requirement locally or globally -Montreal protocol , 1987 – control ozone emission -Earth summit, Rio De Janeiro - Agenda 21, 1992
What are green building materials?
Usage of earth resources sustainable wayNon toxic materialsHave recycled items in them
EMSC 5103 : Sustainable Construction
Green materials Expensive? •Initial cost is expensive
•But when consider the societal costs (which is difficult to quantify) , it is still cheaperGreen products are often competitive to purchase and installation (especially those with recycled materials)•Energy efficient products such as light fixtures and appliances must be evaluated in terms of life cycle analysis as they generally more expensive to purchase and install but less expensive to operate.
Challenge of assessing “greenness”
Standardization and green label , international environmental ISO iso 14000 etc
Selection process 1. Identify material categories2. Identify green building materials option3. Gather technical information4. Review submitted information5. Evaluate “green” materials6. Select and document choice