Sri Lanka’s Construction needs
Sri Lanka’s Prime Minister Ratnasiri Wickremanayake spoke at the Asia Society, Sept 24, 2009 in New York.The prime minister said resettling internally displaced persons (IDPs) is the country’s largest post-war challenge.However, he made clear that a full resettlement would take time. “You cannot have a solution overnight,” he stressed. Wickramanayake said an estimated 280,000 still remain in internment camps, as a result of the conflict.Following both the Tsunami that resulted in an estimated 516,000 displaced survivors, along with the predicament of war refugees Sri Lanka faces a regeneration issue on a massive scale.
The answer to date has been a combination of providing temporary housing for Tsunami victims alongside new developments in the south built in concrete by Contractors external to Sri Lanka.Two year later on from Prime Minister Ratnasiri Wickremanayake speech the problem still exists. The Tsunami temporary housing provided will need to be replaced and the when the external construction companies have completed their projects and departed they leave little legacy beyond the buildings themselves.In the north regeneration is only just beginning following ordnance and mine clearance in many areas.An alternative would be for Sri Lanka to have an industrial alternative to respond to its housing problem as well as other buildings such as schools, municipal and infrastructure buildings.This industry though initialised and set up by external agencies would become wholly Sri Lankan managed and use local materials, labour and management to allow Sri Lanka to create durable, sustainable and climatically appropriate buildings for it’s on use and possibly, in time, export.
Off site Manufactured Buildings
This article discusses a few of the main aspects of Off Site Manufactured buildings (OSM) for a project of either residential units, schools, municipal buildings or hotels to be built in Sri Lanka. It highlights the differences between traditional construction methods and volumetric buildings in areas important to the local area and construction sites as well as long term opportunities for investment, the creation of a new industry and providing employment and social stability.
Hong Kong Factory
Off Site Manufactured Buildings typology:-
Comes in two major forms: either whole volume or flat pack.The Volumetric form of construction is where the main part or large elements of the building is constructed in a factory. Where either whole rooms are constructed including walls, floors ceilings or large elements are made which are then quickly assembled on site. The volume can then be fitted out with all fixtures and fittings from bathrooms and kitchens or large service elements to wall and floor finishes, leaving a small amount of fit out or finishing work to be carried out on site.There are forms of construction also built in factories, such as “flat pack” which offer opportunities and information on systems and suppliers can be supplied if needed.
Topics to be reviewed:-
Areas of interest are the inclusion of existing local industry, contractor services and transportation services for the buildings to the site. Other areas of interest are environmental, sustainability, nuisance factors, waste management and safety ratings of the various factories and building sites, employment and regeneration. Finally of great potential is the legacy following completion of construction projects having created an organisation capable of supplying products to several sectors and several clients both within the national market and abroad by sea.
Other, more detailed reports by DJAS includes information of different volumetric manufacturers by way of example, there are many examples around the world, e.g. UK, Germany, USA, China, Japan which manufacture buildings under factory conditions and they all have their benefits and problems which would require a much longer report that this introductory article allows for, but would provide the basis by which a Sri Lankan enterprise could be started.
What can Off site Manufactured buildings be used for?
They are being used in different sectors in different parts of the world,
Ø They are most commonly used for individual family houses. (USA, Japan, Germany
Ø They are used for Hotels (UK, Germany, France)
Ø They are used for Schools and municipal buildings (UK, USA, Germany, France)
Ø They are used for Pharmaceutical and medical research, as well as hospitals. (UK, Germany,)
Ø They are used for medium rise (7-12 storeys) and high-rise (12 and above to 22 storeys) student accommodation flats. (UK)
Ø They are used for medium rise residential units (UK, USA)
Volumetric Units built in Dublin, Ireland
What are the benefits of utilising Off site Manufactured construction?
Ø High quality product
Ø Finished under factory conditions
Ø Minimal defects
Ø Much reduced damage and theft of materials
Ø Quicker construction durations following design finalisation, achieving between 30 to 50% savings on traditional construction program durations.
Costs for a project:-
Ø Within mature markets where the industry has established itself the product has reached and gone beyond cost parity with traditional construction projects and in some cases has proved to be cheaper. In Sri Lanka with low overheads start up costs would be less than in Europe and over a roughly ten year period should not be prohibitive wit the aim of being on a parity to traditional build techniques.
Risk reduction and costs:-
Ø Because most of the product is constructed in a factory, to factory procedures and systems. The process and costs do not vary due to the weather or site conditions, e.g. monsoon season, therefore the often seen overrun on costs on traditional construction projects is removed for the greater amount of construction process.
Costs, benefits and advice for creating an Indigenous Industry:-
Ø Be being a indigenous enterprise supplying the local market across several sectors and leaving a lasting legacy there will be less need to buy either services or materials and products from abroad, thereby reducing a potential trade deficit.
Ø In time and with local proven success the product can be produced as an export item, thereby increasing the countries income.
Ø Consultancies exist that can provide the most detailed information on how to set up manage and grow a new business in this sector.
Ø Once the business is established it will utilise local talent, have tie ins with Local Universities or encourage Sri Lanka professional staff to return to Sri Lanka from abroad.
Ø Volumetric products have a minimum 60 year structure warranty.
Ø All the modules are also completely insurable and mortgageable.
Ø Foundations for Volumetric buildings offer significant savings in their foundations as well. Generally, only half the stone and concrete of traditional building foundations is used in modular constructions due to their lightweight frames, rigid and robust structure. Volumetric construction is roughly a third of the weight of a full RC frame. This offers further reductions in required site time and nuisance for the surrounding area.
Ø Provides long term employment in the location of the factory both for Professional personnel as well as skilled tradesmen
Ø A new factory will help to regenerate an area by providing permanent employment not only direct to the factory but to all the support services that will grow up around it and its community of workers.
Ø A new construction industry will form the basis for professional and clerical workers to be employed whilst at the same time providing opportunities for Universities in Sri Lanka to provide research and training opportunities leading to a self-sustaining legacy.
Ø This type of construction is flexible and can make use of local raw materials creating further employment.
Ø Working conditions: – It has been measured in the UK and other countries that working in a factory is between 3 to 7 times safer than working on a construction site, less likely to either seriously injure of kill someone whilst at work. The working environment is a better place to work in terms of offices and facilities than on a temporary construction site.
Ø Factory condition mean that materials are used to better effect, there is less waste of materials and those materials, which are wasted, can be easily recycled thereby supporting other industries.
Ø Traditional construction sites create pollution both as contaminants to he ground in spills and water run off as well dust and noise as nuisance to local inhabitants.
Ø It is estimated that waste reduction is 50% better than on site construction.
Embodied Energy: –
Ø As Off Site Manufacture companies manufacture the majority of their buildings from steel components the embodied energy would be less than that for concrete. The steel can be recycled at some later date. The UK Steel Producers federation has produced an assessment stating that lightweight steel construction can achieve between a 200 and 250 years life expectancy if detailed correctly.
Ø In the case of Sri Lanka local materials can be used, such as locally sourced timbers, bamboo, rice husks combined with plant polymers and clay polymer mixes
Environmental Performance: –
Ø Will be a function of the detail design, suffice to say that projects from the USA, UK or Germany can achieve very high levels of energy efficiency this applies to either reducing heating or cooling loads and therefore costs and adds to the buildings attractiveness as a product in that they will be more environmentally comfortable as well as being less expensive to run.
Ø Transportation is a major factor in considering the mode of construction for both safety reasons and environmental reasons due to carbon emissions and costs. Traditionally transport associated with initial construction as well as secondary and recycled product transportation accounts for 25% of energy consumed within the industry, and 10-20% of construction costs. Construction transportation accounts for 16% of the UK’s fuel consumption.
Ø Case studies of Carbon emissions from Construction transport demonstrated how effective Off Site Manufactured constructions are in reducing transportation costs, where for the construction more than 50% of traditional construction vehicle movements were not needed, saving huge amounts of CO2 within the environment. Significant other benefits resulted as well including the increased safety on the roads from less construction movement.
Ø This is because Off Site Manufactured construction is completed within the factory (including fit out) and trucked as one, significantly reducing the amount of deliveries to the site. So that peak travel hours would be less interrupted and delivery could be made much smoother. For example, the modules could be delivered early in the morning before peak hour and during the day they could be assembled during construction hours.