INTRODUCTION

What is sustainable construction?Sustainable construction includes techniques that contribute to creating a healthy environment for the future. This relates to both interior and exterior environments and starts with buildings that are energy efficient. While part of saving energy depends on the everyday practices of individuals, energy efficiency is more than remembering to turn off the light switch when you walk out of the room. With sustainable construction, energy efficiency is built into the structure.

The easiest way to condense what sustainable really means is to remember the 3 Re's. These should apply to construction decisions big and small as you plan your project:

Reduces Re-uses Recycles

Sustainable Construction TechniquesThe following list are some of the techniques recognized in sustainable construction:

Low volatile organic compounds (VOC) paint Plywood processed without using formaldehyde Install big windows that provide plenty of fresh air and natural light Install energy and water efficient appliances Install low-emitting carpet Proper site selection and prevention of pollution on the construction site: For example do not build on:o Prime farmlando In a floodplaino On threatened animal habitato Too close to wetlands Build within walking distance to 10 basic services Provide space for storage and collection of recyclables Establish minimum level of indoor air quality performance Minimize environmental tobacco smoke Build near alternative transportation Reuse or recycle construction materials when possible

“Target issues” for sustainable construction

Based on this concept and to make sustainable construction easier to understand, evaluate and apply, the LafargeHolcim Foundation and its partner universities have identified a set of five “target issues” for sustainable construction, which serve as the basis for the adjudication

process of the LafargeHolcim Awards and as a framework for other activities of the Foundation.

Innovation and transferability – ProgressProjects must demonstrate innovative approaches to sustainable development, pushing the envelope of practice and exploring new disciplinary frontiers. Breakthroughs and trend-setting discoveries must be transferable to a range of other applications.

Innovative concepts regarding design, integration of materials and methods, structure, enclosure and mechanical systems.

Outstanding contributions to construction technologies and building processes, operation and maintenance.

Advancements in the disciplines of architecture, urban and landscape design, civil, urban and environmental engineering, and other fields involved in the production of the built environment.

Long-term monitoring methods to evaluate whether expectations and goals have been met.

Dissemination of knowledge, including project documentation, communication, education and training.

Ethical standards and social inclusion – PeopleProjects must adhere to the highest ethical standards and promote social inclusion at all stages of construction, from planning and building to use and servicing; to ensure an enduring positive impact on communities. Proposals must demonstrate how they enhance the collective realm.

Adherence to ethical standards in all phases of the project. Contributions to the formation of socially-viable environments, strengthening

of shared values and empowerment of communities.

Participation of stakeholders, including users, clients, neighborhood affiliations, local authorities and non-governmental organizations.

Quality of working conditions in the construction industry and including on site; with specific attention given to fair compensation, adequate benefits, safety and gender equality.

Political transparency, unbiased processes and commitment to principled interaction, just practices, all in the effort to prevent corruption at every level.

Resource and environmental performance – PlanetProjects must exhibit a sensible use and management of natural resources throughout their entire life cycle. Long-term environmental concerns, especially pertaining to stocks and flows of material and energy, should be an integral part of the design philosophy.

Minimizing a project’s ecological footprint and maximizing its positive impact on the environment; reduction of harm and increase of beneficial effects.

Environmentally-conscious land use strategies and policies that preserve the natural landscape, while taking water and land reclamation into account.

Emphasis placed on the use of renewable energy in construction, use and upkeep of the built fabric to reduce CO2 emissions and avoid toxicity.

Innovative deployment of material resources in construction with an emphasis on cradle to cradle cycles, mining existing building stocks and reduction of waste.

Resilient products, robust construction details, smart interaction of building systems and environmentally sound technologies.

Economic viability and compatibility – ProsperityProjects must prove to be economically feasible with regard to channeling and managing financial flows, promoting an economy of means and be compatible with demands across the construction’s lifespan.

Integration of the project into larger economic frameworks of local, regional, and global monetary flows that show a positive impact of the economy on society and the environment.

Funding sources and profits earned must be legitimate and transparent.  Projects must be affordable and operating costs over a structure’s lifetime

determined in reference to returns on investment. Flexibility to adapt to future changes of user needs, ownership, laws,

regulations, and economic fluctuations. Innovative economic models are sought that take external costs into

consideration.

Contextual and aesthetic impact – Place Projects must convey a high standard of architectural quality as a prevalent form of cultural expression. With space, form and aesthetic impact of utmost significance, the material manifestation of the design must make a positive and lasting contribution to the physical, human and cultural environment.

Improvement of existing contextual conditions responding to the natural and built environment.

Interdependencies of landscape, infrastructure, urban fabric and architecture.

Working with the given building stock through sensitive restoration, re-use or re-modeling of the built environment.

Inventive programming strategies in terms of use, multiplicity of functions, short-term flexibility and long-term adaptability.

Architectural quality and aesthetic impact, specifically concerning space, spatial sequences, movement, tactility of materials, light and ambiance.Key issues in Sustainable Construction

This section details the key issues currently facing the construction industry surrounding sustainability.

Corporate ResponsibilityThe construction industry has been slow to respond to the Corporate Responsibility but increasing regulation in areas such as carbon emissions and waste are forcing companies to improve their processes and many clients are beginning to demand responsible approaches to design and construction.

Corporate Responsibility (CR) is about improving the way that businesses respond to the needs of stakeholders and ensure the sustainability of their activities. This means that it is relevant to companies of all sizes within the industry supply chain, including clients, designers, contractors and the suppliers of materials.

What is it?Business in the Community (BITC) defines Corporate Responsibility (CR) as:“the management of a company’s positive impact on society and the environment through its operations, products or services and through its interaction with key stakeholders such as employees, customers, investors and suppliers”

Constructing Excellence, taking BITC’s lead, considers Corporate Responsibility to be made up of four elements:

Environment Workplace Community Marketplace

EnvironmentIssues to consider when developing the CR strategy of a construction business include climate change mitigation in new builds and business operations, as well as adapting for future climate change conditions. Water management, including drainage and water conservation, is another crucial issue to environmental CR, as are considerations of biodiversity and waste reduction (on site and in the office).

WorkplaceFair treatment of staff, discrimination prevention and workplace accessibility form an essential part of any Corporate Responsibility strategy. The Investors in People Standard is a framework for developing strategies, taking action and evaluating the impact of performance. Considerations of time management, office environment, health and safety, diversity and recruitment and skills development are crucial to any CR strategy.

CommunityA successful CR strategy will seek to engage with the community on a local and sometimes global scale. Companies can have positive influence on the areas in which they work through job creation, creation of training opportunities and apprenticeships, volunteering opportunities for staff and partnering with national and international charities. It is important to consider issues surrounding sustainable communities, the impacts of the construction process on communities and volunteering.

MarketplaceResearch conducted by Arthur D little and Business in the Community found that nearly 70% of CEOs say that Corporate Responsibility is “vital” to profitability. Therefore a company that operates in an ethical fashion and considers environmental and social factors can improve its economic performance. Consideration of procurement of construction products and in the office is key, as is working with the supply chain to align CR values and policies.

Why is it important?Research shows that companies that embrace CR are often more financially viable than those that do not. Forum for the Future found the majority of studies carried out between the 1970s and 1990s reported a positive correlation between CR performance and financial performance.

An effective CR approach can lead to benefits in the following areas:

Reputation management Risk management Employee satisfaction Innovation and learning Access to capital Financial performance

In addition, customers, clients and job-seekers are increasingly interested in the values of the organization’s they are looking to work with, which is possible through corporate responsibility reporting.

Energy, Pollution & Climate ChangeThe construction industry is responsible for the intensive use of energy in the creation of buildings and infrastructure and in the operational phase, and the production of carbon dioxide and other pollutants.

The construction industry is responsible for the intensive use of energy both directly, in the creation of buildings and infrastructure, and indirectly, in the operational phase. As well as the carbon dioxide which is produced, a variety of other pollution is caused by construction processes and buildings in use.

Thoughtful planning and design can have a major impact on reducing energy use and pollution over a building’s entire lifetime. The number of more sustainable solutions is growing rapidly and many of these can provide substantial financial savings, as well as environmental benefits. This is particularly the case when they are considered at the earliest possible stage of a project and where longterm benefits are fully taken into account.

What is it?Energy from fossil fuels, nuclear power, hydropower and wind power is used in the construction process during the manufacture of materials, construction of buildings and infrastructure and throughout the operation of buildings during their lifetime. The use of non-renewable energy contributes to climate change through the production of CO2 emissions.

The construction industry in its manufacture of materials, the construction process and the end-use of buildings produces a number of gases and other emissions, such as greenhouse gases (carbon dioxide (C02), water vapour, methane and nitrous oxide) and the pollutants produced by synthetic chemicals used in the construction process.

Why is it important?Achieving targets for global reductions in CO2 emissions will be a major challenge as demand for energy increases, and particularly in the light of accelerating development in countries such as China and India. The potential for using energy more efficiently should not be underestimated. We already have a huge range of options for reducing energy use in existing homes, offices and other commercial buildings.

Greenhouse gases are naturally occurring, however when produced in excessive quantities they can contribute significantly to climate change. Carbon Dioxide (CO2) is currently the most significant greenhouse gas because it accounts for 60% of the ‘enhanced greenhouse effect’ which, in turn, is responsible for man-made global warming. The greenhouse effect means that the sun’s rays are trapped and build up in the atmosphere, causing temperatures to rise – the 1990’s was the warmest decade for the last millennium. Pollutants caused by synthetic chemicals can be harmful to the environment and human health.

Existing StockRefurbishment of the existing building stock, including heritage buildings, will be crucial if the current UK government emissions targets are to be reached. The methods used in the construction phase of refurbishment, as well as their end-use, have impacts on their sustainability.

Materials & WasteThe construction industry produces a quarter of total waste each year of which up to 13% is delivered and unused. It produces three times more waste than all UK households combined.

Much of the waste from construction is potentially hazardous and disposal should be carefully planned. However, whatever the nature and characteristics of the waste may be, it all has one thing in common:  it represents a loss of resources, loss of money and reduced sustainability. In particular, traditional waste disposal, such as landfill and incineration, can cause serious environmental damage.

What is it?Some of the main types of waste resulting from the construction include: tiles, wood, insulation, concrete, plastic, brick and block, lead pipes, asphalt, ferrous and non-ferrous, glass, metals, paint and roofing materials.

Why is it important?Historically, landfill sites have been the most common method of organized waste disposal. According to a recent report by the Wates Group (2006), the UK construction industry sends 36 million tonnes of waste to landfill sites each year.

The potential impacts of landfill are as follows: leakage, methane emissions, odour problems, damage to roads caused by heavy vehicles, noise pollution

from vehicles and machinery, local air pollution particularly in the form of dust, nuisance and disease (e.g. from rats and flies). Landfill taxes are set to rise and there are serious penalties for fly-tipping offenders.

Construction waste is therefore a financial, social and environmental issue that needs to be tackled by following the Waste Hierarchy – Reduce, Reuse, Recycle.

SkillsUp skilling employees, the supply chain and the local community can have a positive impact on the sustainability of a business and community, such as greater employment, job satisfaction and business productivity.

Sustainable CommunitiesSocial aspects are often missed out of the construction industry’s considerations of sustainability despite the important effect that they have on long-term value for money and the well-being of building occupants.

The social impacts of construction start early in the construction phase and continue for as long as the structures remain standing.

What is it?The Bristol AccordIn December 2005, during the UK presidency of the EU, ministers from member states met in Bristol to discuss and agree the benefits of creating sustainable communities across Europe. The ‘Bristol Accord’, which they were asked to endorse, included eight characteristics of a sustainable community and a commitment to sharing good practice on case studies. The eight characteristics are as follows:

Well Run: With effective and inclusive participation, representation and leadership.

Well Connected: With good transport services and communication linking people to jobs, schools, health and other services.

Well Served: With public, private, community and voluntary services that are appropriate to people’s needs and accessible to all.

Environmentally Sensitive: Providing places for people that are considerate of the environment.

Thriving: With a flourishing and diverse local community. Well designed and built: Featuring quality built and natural

environment.

Fair for everyone: Including those in other communities, now and in the future.

Active, inclusive and safe: Fair, tolerant and cohesive with a strong local culture and other shared community activities.

Ministers agreed the importance of fostering skills for successful place making and the value of cooperative activity on this theme across member states.

Why is it important?Some of the tower blocks which were rapidly built in the 1960s, together with poor building/estate management, are now widely seen as the root of serious social problems. Community issues have included low levels of well-being, increased depression and high levels of crime. Developments like these didn’t properly consider the requirements of the communities involved.

Sustainable ProcurementThe procurement of goods, services and buildings has traditionally been based on two overriding considerations: price and quality. However, the choices people make about what they buy and how they buy it can have a huge impact on all aspects of sustainable development.

What is it?Sustainable procurement isn’t just a question of choosing the most environmentally friendly products. It is about achieving the best possible value for money over the long term and should include economic and social, as well as environmental, considerations.

In June 2006, the government published ‘The National Action Plan: Procuring the Future’. It aims to deliver sustainable procurement, to stimulate innovation through public procurement and to complement and build on existing activity on the subject. It clearly explains how public spending can be used to combat climate change as well as promoting social progress.

Why is it important?One of the key barriers to more sustainable procurement is the belief that it will always cost more. However, this is certainly not always true. In many cases costs can actually be cut by reducing waste, increasing resource efficiency and promoting innovative new products.

WaterWater supplies are a growing cause for concern for the construction sector, which has particularly high requirements especially in the manufacture of materials such as steel and concrete. Most construction activity needlessly uses clean, drinkable water supplies and there is no reason why many processes couldn’t use water treated to less exacting standards.

What is it?The huge industrial demands on water supplies are a growing cause for concern and the construction sector has particularly high requirements, especially in the manufacture of materials such as steel and concrete. Once a building is in use, demands for mains-supplied water can be a further major drain on resources. High density office buildings in urban areas, for example, often have very high requirements.

Why is it important?With weather patterns becoming more unpredictable both in the UK and globally it is increasingly important to consider the conservation of clean, fresh supplies of water – not least in the design and use of buildings

Most construction activity needlessly uses clean, drinkable water supplies and there is no reason why many processes couldn’t use water treated to less exacting standards. If such high consumption continues, we will face a future where water companies won’t be able to guarantee continuity of supply through a dry summer. Measures to limit water use, such as hosepipe bans, are likely to become much more common.

PRACTICAL APPLICATIONS OF SUSTAINABLE CONSTRUCTION

COCHIN INTERNATIONAL AIRPORT

Standing out in a field of green are more than 46,000 solar panels tapping the power of the bright sunlight and converting it into energy. Located in the southern state of Kerala, Cochin is now the first airport in the world to run completely on solar power.

The airport started with a small pilot project by installing a solar energy plant with 400 panels on its rooftop in 2013. When that experiment succeeded, it decided to go all the way.

In August this year, the airport became totally self-sufficient in meeting its energy needs after it installed a 12 megawatt solar plant close to the cargo terminal. The airport's managing director VJ Kurian says it was the huge power bills that prompted them to look at greener solutions.

The airport, which is the seventh busiest in India handling more than 1,000 flights a week, consumes nearly 48,000 units costing 336,000 rupees ($5,160; £3,364) every day. Today, with its solar power plant it produces more energy than it needs and banks the rest with the state power grid for rainy days and night-time requirements.

Mr. Kurian says airports across the country have approached him to learn more about the "Cochin model". A team from Liberia is also interested to learn more about harnessing the sun's energy.

The installation of the solar plant cost nearly $9.5m (£6.27m) and took around six months to complete. The company is hopeful of recouping the

costs in less than six years. So far it has been a smooth journey for the airport, says Mr. Kurian.

The airport is looking to inaugurate a new international wing in January comprising nearly 1.5m sq. ft. which will require more energy than what the existing plant is generating. Additional solar panels will have to be set up if the authorities wants to hang onto the "first fully solar powered airport" tag.

Cochin may have shown the way forward but the rest of India is not far behind in tapping the vast potential of the sun. As most parts of the country receive sunshine for over 300 days a year, the possibilities are plenty. Recognizing this, Prime Minister Narendra Modi has outlined his vision of increasing the country's solar power capacity to 100,000 megawatts by 2022.

This is a dream that can be realized by having photovoltaic panels on the rooftop of every home in India, generating enough power to reduce the country's massive fuel bill and dependence on fossil fuels. Solar energy is also a much cleaner source of energy than conventional forms of energy like thermal and nuclear. Considering the global debate on climate change, developing economies like India with its ever increasing need for energy to fuel growth can turn to the sun to power ahead.

The solar plant at Cochin airport will produce 18 million units of power from the sun annually which is enough to meet the energy needs of 10,000 homes for one year. The bonus is the environmental benefit of reducing carbon dioxide emissions by more than 300,000 metric tons which is equal to planting three million trees or not driving 750 million miles.

In a country where more than 300 million people still have no access to power, going solar may just be the solution that is needed to light up their lives.

PASSIVE HOUSESThe term passive house refers to a rigorous, voluntary standard for energy efficiency in a building, reducing its ecological footprint. It results in ultra-low energy buildings that require little energy for space heating or cooling.

Passive solar building design and energy-efficient landscaping support the Passive house energy conservation and can integrate them into a neighborhood and environment. Following passive solar building techniques, where possible buildings are compact in shape to reduce their surface area, with principal windows oriented towards the equator - south in the northern hemisphere and north in the southern hemisphere - to maximize passive solar gain. However, the use of solar gain, especially in temperate climate regions, is secondary to minimizing the overall house energy requirements. In climates and regions needing to reduce excessive summer passive solar heat gain, whether from direct or reflected sources, Brise soleil,trees, attached pergolas with vines, vertical gardens, green roofs, and other techniques are implemented.

Passive houses can be constructed from dense or lightweight materials, but some internal thermal mass is normally incorporated to reduce summer peak temperatures, maintain stable winter temperatures, and prevent possible overheating in spring or autumn before the higher sun angle "shades" mid-day wall exposure and window penetration. Exterior wall color, when the surface allows choice, for reflection or absorption insolation qualities depends on the predominant year-round ambient outdoor temperature. The use of deciduous trees and wall trellised or self-attaching vines can assist in climates not at the temperature extremes.

In addition to using passive solar gain, Passive house buildings make extensive use of their intrinsic heat from internal sources—such as waste heat from lighting, white goods (major appliances) and other electrical

devices (but not dedicated heaters)—as well as body heat from the people and other animals inside the building. This is due to the fact that people, on average, emit heat equivalent to 100 watts each of radiated thermal energy.Together with the comprehensive energy conservation measures taken, this means that a conventional central heating system is not necessary, although they are sometimes installed due to client skepticism. Instead, Passive houses sometimes have a dual purpose 800 to 1,500 watt heating and/or cooling element integrated with the supply air duct of the ventilation system, for use during the coldest days. It is fundamental to the design that all the heat required can be transported by the normal low air volume required for ventilation. A maximum air temperature of 50 °C (122 °F) is applied, to prevent any possible smell of scorching from dust that escapes the filters in the system.Typically, passive houses feature:

Fresh, clean air: Note that for the parameters tested, and provided the filters (minimum F6) are maintained, HEPA quality air is provided. 0.3 air changes per hour (ACH) are recommended, otherwise the air can become "stale" (excess CO2, flushing of indoor air pollutants) and any greater, excessively dry (less than 40% humidity). This implies careful selection of interior finishes and furnishings, to minimize indoor air pollution from VOC's (e.g., formaldehyde). This can be counteracted somewhat by opening a window for a very brief time, by plants, and by indoor fountains.

Because of the high resistance to heat flow (high R-value insulation), there are no "outside walls" which are colder than other walls.

Homogeneous interior temperature: it is impossible to have single rooms (e.g. the sleeping rooms) at a different temperature from the rest of the house.

Slow temperature changes: with ventilation and heating systems switched off, a passive house typically loses less than 0.5 °C (1 °F) per day (in winter), stabilizing at around 15 °C (59 °F) in the central European climate.

Quick return to normal temperature: opening windows or doors for a short time has only a limited effect; after apertures are closed, the air very quickly returns to the "normal" temperature.

COSTS INVOLVED

In the United States, a house built to the Passive House standard results in a building that requires space heating energy of 1 BTU per square foot (11 kJ/m²) per heating degree day, compared with about 5 to 15 BTUs per square foot (56-170 kJ/m²) per heating degree day for a similar building built to meet the 2003 Model Energy Efficiency Code. This is between 75 and 95% less energy for space heating and cooling than current new buildings that meet today's US energy efficiency codes.

In the United Kingdom, an average new house built to the Passive House standard would use 77% less energy for space heating, compared to the circa-2006 Building Regulations.

In Ireland, it is calculated that a typical house built to the Passive House standard instead of the 2002 Building Regulations would consume 85% less energy for space heating and cut space-heating related carbon emissions by 94%