Learning Outcome Lesson Objective Environmental Issues
Understand the implications of the issues and constraints on building construction Lesson Objective To be able to explain the environmental impact resulting from materials and methods used in construction Environmental Issues Recap L04: Understand the implications of the issues and constraints on building construction
What are the main threats to environmental sustainability? Global warming a gradual increase in the overall temperature of the earth's atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, CFCs, and other pollutants Resource depletion Both renewable and non-renewable Pollution Air, water, and land Which is the most immediate? Global warming as resource depletion and pollution contribute to it. L04: Understand the implications of the issues and constraints on building construction
What are the three areas that link together to provide sustainable development? The triple bottom line L04: Understand the implications of the issues and constraints on building construction
Construction activities statistics Energy from fossil fuels consumed in the construction and operation of buildings accounts for approximately half of the UKs emissions of carbon dioxide. Construction and Sustainable Development Plain English, Constructing Excellence, Section 2, Page 5, 01/01/08 More than 400 million tonnes of materials get delivered to site each year. Of these 60 million tonnes go straight to tip due to over ordering, damage resulting for poor storage or because of inappropriate ordering. Time to bin industrys lavish habits by Mike Baker, Thursday 20th March Construction News, Issue 7060 Over 90% of non-energy minerals extracted in the UK are used to supply the construction industry with materials. Construction and Sustainable Development, Plain English, Constructing Excellence, Section 2, page 4, 01/01/08 L04: Understand the implications of the issues and constraints on building construction
What can we do? Designers? Contractors? Building users? L04: Understand the implications of the issues and constraints on building construction
Raising the standards. The code for sustainable homes is the national standard for the sustainable design and construction of new homes. It aims to reduce carbon emissions and promote higher standards of sustainable design above the current minimum standards set out by thebuilding regulations. L04: Understand the implications of the issues and constraints on building construction
The code for sustainable homes The code provides 9 measures of sustainable design: energy/CO2 water materials surface water runoff (flooding and flood prevention) waste pollution health and well-being management ecology In groups of 2/3 discuss what could be incorporated under each heading. L04: Understand the implications of the issues and constraints on building construction
The code for sustainable homes It uses a 1 to 6 star system to rate the overall sustainability performance of a new home against these 9 categories. The code is voluntary. The only circumstances where the code can be enforced are where: local councils require developers to comply with the code by including a requirement in their planning policy affordable housing is funded by the Homes and Community Agency that requires homes to be built to code level 3 the level 3 energy standard is now incorporated in the building regulations L04: Understand the implications of the issues and constraints on building construction
The code for sustainable homes How would living in a Code 6 home benefit the homeowner? Lower energy consumption Greater water efficiency Better air quality Environmental kudos L04: Understand the implications of the issues and constraints on building construction
Extraction and manufacture What are fossil fuels? Fossil energy sources, are non-renewable resources that formed when prehistoric plants and animals died and were gradually buried by layers of rock. Over millions of years, different types of fossil fuels were formeddepending on what combination of organic matter was present, how long it was buried and what temperature and pressure conditions existed as time passed. Fossil fuels are:- Oil Gas Coal L04: Understand the implications of the issues and constraints on building construction
What are the disadvantages of using fossil fuels? Fossil fuels are non-renewable energy resources. Their supply is limited and they will eventually run out. Fossil fuels release carbon dioxide when they burn, which adds to the greenhouse effect and increases global warming. Of the three fossil fuels, for a given amount of energy released, coal produces the most carbon dioxide and natural gas produces the least. Coal and oil release sulfur dioxide gas when they burn, which causes breathing problems for living creatures and contributes to acid rain. L04: Understand the implications of the issues and constraints on building construction
Our economy is largely dependent on fossil fuels. Reducing CO2 emissions is the most significant issue when constructing buildings. Designers and contractors have a duty to produce homes, and buildings that are energy efficient, reduce heat loss and have energy efficient appliance. In groups discuss how a home could be made more energy efficient. L04: Understand the implications of the issues and constraints on building construction
Consider how different construction methods affect the environment. Prefabrication Sourcing locally Waste segregation Discuss and list the advantages associated with each. L04: Understand the implications of the issues and constraints on building construction
Complete waste worksheet L04: Understand the implications of the issues and constraints on building construction
Material Choice What is embodied energy? The embodied energy (carbon) of a building material can be taken as the total primary energy consumed (carbon released over its life cycle). This would normally include (at least) extraction, manufacturing and transportation. L04: Understand the implications of the issues and constraints on building construction
How can energy used to manufacture and deliver materials be reduced? Try to reuse materials and topsoil already on site, and give preference to low energy materials. Source materials locally, reducing delivery journeys and supporting the local economy. Ensure that contractors do likewise by examining their supply chain Use reclaimed materials (e.g. second-hand timber) and recycled materials (such as glass / concrete or brick rubble for aggregates) for construction. L04: Understand the implications of the issues and constraints on building construction
What are the advantages of using local materials? Contributes to lowering carbon emission levels and saving resources by reducing carbon miles in transporting goods. Could save on packaging and transport costs. Strengths local economy by keeping money in the area which could help to create new jobs within the local community. Buying from a local independent business can benefit from local knowledge and expertise and often, the price difference is minimal due to transport savings. Cost savings from 'bargain' online suppliers could be lost if a long-distance delivery doesnt turn up on time, arrives damaged or incomplete. This could cause major delays for a project and with contractors hanging around waiting for a delayed delivery, this will add to the budget. Learning Outcome Lesson Objective Environmental Issues
Understand the implications of the issues and constraints on building construction Lesson Objective To be able to explain the environmental impact resulting from materials and methods used in construction Environmental Issues Noise Pollution L04: Understand the implications of the issues and constraints on building construction
Noise What is noise? Definition-unwanted sound by the listener Sound a wave motion carried by the air Units the decibel (dB), using a logarithmic scale, which means that an increase of 10 dB equates to a doubling in loudness L04: Understand the implications of the issues and constraints on building construction
Noise propagation Noise will generally radiate in all directions, it will bend around and over walls and buildings It will reflect back off solid surfacescertain operations will generate more noise in one direction than another so careful orientation can have benefits Screening between source and receiver is effective if it obscures the direct line of site between the two L04: Understand the implications of the issues and constraints on building construction
Why is noise important? Excessive noise on site can represent a major hazard to site workers andannoy neighbours Noise is the source of the majority of off-site complaints Noise can disturb wildlife and natural heritage L04: Understand the implications of the issues and constraints on building construction L04: Understand the implications of the issues and constraints on building construction
Controls Limiting the time for noisy activities Introduce screening between source and receiver Controls at source Working noise level dB (A) Average noise allowed
L04: Understand the implications of the issues and constraints on building construction Working noise level dB (A) Average noise allowed Actualworking time allowed 75 60 minutes 78 30 minutes 81 15 minutes 85 6 minutes L04: Understand the implications of the issues and constraints on building construction
Managing noise on site Threefactors which influence noise levels at a given point: Site management and construction method Plant Screening L04: Understand the implications of the issues and constraints on building construction
Checklist duty of care Change working method Reduce noisy assembly practices (off-site) Isolate noisy plant Adopt working hours to restrict noisy activities to certain times Arrange delivery times to suit the area Route construction vehicles to take into account a reduction in noise and vibration Maintain haul roads Liase with conservation bodies to minimise noise disturbance (disruption) to any sensitive wildlife L04: Understand the implications of the issues and constraints on building construction
BACKGROUND Noise pollution is traditionally not placed among the top environmental problems facing the society; however, it is one of the more frequently encountered sources Sources of noise pollution are extremely diverse and are constantly increasing as more and more noise-generating products become available to consumers. An estimated 6% citizens are exposed to noise that poses a threat to their hearing. In today's mechanized world it is virtually impossible for an active person to avoid exposure to potentially harmful sound levels. L04: Understand the implications of the issues and constraints on building construction
It is often possible to reduce noise radiation from production equipment, material handling, and work in progress; for example by damping sound radiating panels, quietening power sources and transmissions, and reducing noise from compressed air exhausts. Sometimes machine alterations or enclosures do not give sufficiently good results, and if it is the work process itself which causes intense noise it can be difficult to predict the results of noise control measures. In such cases effort might be better aimed at changing the working methods and processes themselves. L04: Understand the implications of the issues and constraints on building construction
Changing the method of work is the only way to get to grips with noise generation; it requires that production equipment or part of it must be replaced and one must be aware of the availability of less noisy equipment for both production and material handling. Requires cooperation between the buyer, supplier, designer, and safety organization. L04: Understand the implications of the issues and constraints on building construction
Preventing propagation to avoid noise pollution can result economically more efficient than corrective measures. The noise in a workshop is often dominated by a relatively small number of intense noise sources. Try to enclose all noise sources points or keep them away from workers in the same room. By setting up sound absorbing ceiling and wall panels, noise levels within the room far from the noise sources can be reduced. Alteration and replacement of production equipment may mean that personnel monitoring this machinery do not need to be in its vicinity if monitoring can be carried out in a sound insulated control room. Learning Outcome Lesson Objective Environmental Issues
Understand the implications of the issues and constraints on building construction Lesson Objective To be able to explain the environmental impact resulting from materials and methods used in construction Environmental Issues Dust Pollution L04: Understand the implications of the issues and constraints on building construction
Control of Dust L04: Understand the implications of the issues and constraints on building construction
Nuisance dust activities are a common and well-recognised problem. Fine particles (less than 10 m in diameter, known as PM10) from these sources are now recognised as significant causes of pollution. Why? Owing to their small size, they can be carried from sites even in light winds and may therefore have an adverse effect on the local environment and on the health of local residents, as well as on those working on the site. L04: Understand the implications of the issues and constraints on building construction
Under Part IV of the Environment Act, (1995) and the UK Air Quality Strategy, Local Authorities are required to work towards achieving national air quality objectives. Construction site operators will therefore need to demonstrate that both nuisance dust and fine particle emissions from their sites are adequately controlled and are within acceptable limits. L04: Understand the implications of the issues and constraints on building construction
Health effects from particles and fibres from certain materials are immediate while those from other types of materials may take many years to develop. It is therefore essential that exposure to all forms and sizes of particle pollution is kept to a minimum, both for workers on site and for other people living and working outside the site boundary. L04: Understand the implications of the issues and constraints on building construction
In groups of 2/3 discuss and list the benefits of reducing dust pollution lessening of the impact on local air quality reduction in the soiling of property, thereby reducing the costs of cleaning reduction in the level of complaint from local residents reduction in the number of environmental offences and hence prosecutions by Local Authorities less time and money wasted in defending prosecutions and repairing environmental damage reduction in the site engineers workload by avoiding conflicts potential for increased future business enjoyment of the benefits of increased profit. L04: Understand the implications of the issues and constraints on building construction
How can dust be controlled? Dust and fine particle generation from construction and demolition activities can be substantially reduced through carefully selected mitigation techniques and effective management. Once particles are airborne, it is very difficult to prevent them from dispersing into the surrounding area. The most effective technique is to control dust at source and prevent it from becoming airborne, since suppression is virtually impossible once it has become airborne. L04: Understand the implications of the issues and constraints on building construction
Dust control measures commonly used L04: Understand the implications of the issues and constraints on building construction
Worksheet task Consider how dust is created by the following activities, and how they can be mitigated. Roads, surfaces and public highways Static and mobile combustion plant emissions Site preparation and restoration after completion Demolition Construction and fabrication processes Internal and external finishing and refurbishment L04: Understand the implications of the issues and constraints on building construction
before after L04: Understand the implications of the issues and constraints on building construction
The main problems we experience concerning dust L04: Understand the implications of the issues and constraints on building construction
What is Silica? Silica is one of the most abundant minerals on earth and found naturally in masonry, stone, sand and aggregates. Its also used in the manufacturing of a huge range of building materials including bricks, blocks, mortar, roof tiles and concrete products. Materials containing silica are perfectly safe, but when the materials containing silica are subjected to everyday site activities such as cutting, drilling, grinding and sanding, very fine dust particles can be released into the air. L04: Understand the implications of the issues and constraints on building construction
SUBSTANCE % SILICA CONTENT Brick Up to 30 Concrete, cement, mortar 25 to 70 Tile 30 to 45 Sandstone, gritstone, quartz More than 70 Granite Sand, gravel, flint Slate Up to 40 L04: Understand the implications of the issues and constraints on building construction
Silcosis When you breathe in air containing dust, the hairs and mucus in your nose and throat trap the large dust particles but the fine RCS particles are respirable meaning they are carried deep into the lungs where oxygen is extracted from the air. The RCS particles are deposited here causing inflammation and scarring known as silicosis, which makes breathing more difficult and increases the risk of developing lung infections and lung cancer. L04: Understand the implications of the issues and constraints on building construction
Environmental Protection Act (EPA) (1990) The EPA (1990), under Section 79, states that where a statutory nuisance is shown to exist, the Local Authority must serve an abatement notice. Statutory nuisances are defined as: any dust or other effluvia arising on industrial, trade or business premises and being prejudicial to health or a nuisance any accumulation or deposit which is prejudicial to health or a nuisance. Legislation relating to occupational exposure
L04: Understand the implications of the issues and constraints on building construction Legislation relating to occupational exposure Health and Safety at Work Act (1974) This is the principal statute for reducing health and safety risks and protecting people during workplace activities. It is a criminal statute and does not give rise to any civil liability. The Control of Substances Hazardous to Health (COSHH) Regulations, (1994) Under COSHH Regulation 2, one of the definitions of substances regarded as hazardous to health includes: dust of any kind, when present in substantial concentration in the air. L04: Understand the implications of the issues and constraints on building construction
Clean Air Act (1993) Under the Clean Air Act (1993), open fires are not recommended on site since emissions of dark smoke are prohibited from any industrial or trade premises (e.g. construction or demolition sites). However, the burning of timber and other waste resulting from the demolition of a building is exempt from this. The following conditions, however, are essential for the exemption to apply. There must be no other reasonably safe and practicable method of disposal. The emission of dark smoke must be minimised. The burning must be carried out under direct and continuous supervision.