Building System For Public Housing In Malaysia
The Malaysia construction industry plays an important role in generating wealth to the country and development of social and economic infrastructures and building. The industry provides job opportunities for 800,000 people which represented 8% of total workforce (CIMP, 2006). The construction industry is one of the productive sectors that constantly contribute to the economy.
According to CIDB (2003), the IBS is a construction technique in which components are manufactured in a controlled environment (on or off site), transported, positioned and assembled into a structure with minimal additional site works. IBS is not new to the construction industry in Malaysia. Only it has now remerged worldwide into the 21st century as a reasonable solution to improve overall construction image and performance. The Malaysia government has spared no effort to bring IBS to the drawing tables of all professionals involved in the built environment. Based on the IBS Roadmap (2003), the IBS Roadmap 2003-2010 has been endorsed by the Cabinet of Ministers to be the blueprint document for the industrialisation of the Malaysia construction sector.
This is because under the Seventh Malaysia Plan (1996-2000) the Government of Malaysia for the first time to introduced the Low Medium Cost Housing category (the previously it was classified together with medium cost housing category) due to the always increasing demand for housing in this category. In additional, it is to ensure that the middle low income group with salary ranging from RM1,501.00 to RM2,500.00 per month and able to own a house. However, the pricing of low medium cost housing are around RM42,001.00 to RM60,000.00 per unit only. Using IBS in this types of housing project are more suitable because high volume and stability of demand for buildings is the advantages of using IBS. Besides that, it will also reduce the selling price of low medium cost housing.
The IBS is a manufactured the building components at factories (off site manufacture), will enable cost saving; safety and health; productivity and quality improvement through the reduction of labour intensity and construction standardisation. Apart from this method, it also offers minimal site wastage, less site materials, cleaner and neater environment, controlled quality, and lower total construction costs.
Using higher percentage of IBS in the construction of public housing and other building projects will provide better productivity, quality, and safety, especially for the total construction time saving and cost saving. IBS will contribute towards a better construction industry, as well as improve the global competitiveness of Malaysian builders. Nowadays, IBS in Malaysia become more popularity in the construction industry especially for the Government project. An early effort by the Government of Malaysia to promote usage of IBS and develop an Open Building system (OBS) concept as an alternative to conventional and labour intensive construction method has yet to make headway.
According to Works Minister Datuk Mohd Zin Mohamed, the prefabricated parts will be used in all Government projects in a proposal to reduce the dependence on foreign workers. Besides that, it wills also reducing inherent social problems involving these foreign workers. The use of prefabricated parts was part of the IBS which would be adopted for all Government projects. The Government of Malaysia has ordered all government agencies carrying out development and people’s housing projects to use at least 70% IBS content in those projects.
Aim
A study into using IBS in the public housing in Malaysia and the popularity apply in the construction.
Objectives
To study the history of IBS in public housing.
To study the classification of various types of IBS and apply to public housing.
To identify the benefits and barriers of the IBS in public housing.
To identify as a potential method to improve overall construction performance.
To identify as a popularity for public housing.
Hypothesis
Apply IBS into public housing will be one of the better construction methods to construct the building. For the future, the IBS will become more and more popularity for construction industry in Malaysia. For the construction cost, time and quality, IBS will be the better one to control all the construction cost, to speed up the construction times and to provide high quality of components.
Background
Since early 1960s, IBS has been introduced in Malaysia by the use of precast concrete beam-column element and panelized system (Thanoon, 2003). Nearly, 22.7 acres of land along Jalan Pekeliling was dedicated to the project comprising seven blocks of 17-storey flats (about 3,000 units of low-cost flat and 40 shop lots). These first pilot projects are using the Danish System of large panels in a prefabricated system. The second pilot project is a six block of 17-storey flats and three blocks of 18-storey flats at Jalan Rifle Range and using French Estoit System.
Apply the IBS in the construction industry will improve overall construction performance such as standardization, total quality improvement, reduce defect, waste reduction, cost saving and etc. But nothing in this world is perfect, so some barriers of using IBS in the construction industry will be the poor knowledge of install IBS, lack of guidance, lack of professional trained in IBS and etc.
Based on IBS Roadmap (2003), IBS Roadmap 2003-2010 was developed and published to steer the direction of IBS implementation and promotion activities and guide the practitioners and policy makers on IBS related issues.
Scope and limitation of study
This paper shall identify the common types of IBS in the construction industry and apply into public housing in order to determine their impact on construction projects and popularity for the public housing. This study is part of the ongoing research appraising and analyzing how we use the IBS in construction and how many percentage of IBS are using in the construction project. Therefore, this study will include the following areas:
Definition of IBS in public housing.
The history of the IBS for public housing in Malaysia.
Classification of IBS in Malaysia.
Various types of IBS in construction industry and which one is more useful for public housing.
The advantages and disadvantages of using IBS for public housing.
The selling price and the popularity using IBS for public housing to the contractor.
Research Methodology
Literature Review
In the beginning, literature review was conducted to determine an overall idea regarding IBS for public housing. This refers to collecting the latest secondary data and information from different sources which including books, journals, magazines, dissertations, conference papers, and information from the internet. These materials were used for background reading to obtain full understanding and information needed for discussion and analysis in the research.
Questionnaires
A questionnaire is a research instrument consisting of a series of questions and other prompts for the purpose of gathering information from respondents. The questions will centre on the KL areas mentioned in the above objectives. A multi-option format will be designed and limited to about 30 questions, in order to obtain a high level of response.
Project Plan and Schedule
Chapter 1 : Introduction
This chapter will include the project title, rationale of the study, scope and limitation of study, research goals and methodology. In addition, aims, objective and hypothesis of the study are included under the research goals.
Chapter 2: Literature Review
This chapter will display the definition of IBS, history of IBS for public housing, classification of IBS in Malaysia, and benefits and barriers of using IBS in construction project for public housing and this literature review will base on the dissertation objectives.
Chapter 3: Research Methodology
This chapter will discuss on the technique for data collection to achieve the dissertation’s aim and objective. Besides, it also includes the research sample and method of analysis for the feedback obtained from the respondents.
Chapter 4: Data Analysis
This chapter wills surveys and analysis the data collection from the contractor, consultant and developer of people about their opinions, behaviour or knowledge.
Chapter 5: Conclusion
The conclusion will include summary on the dissertation from chapter 1 to chapter 4 together all the research result to present the overall findings and make appropriate recommendations.
References
CIDB, 2003. IBS Roadmap 2003-2010. Malaysia: CIDB.
CIDB, 2003. National IBS Survey, 2003. Malaysia: CIDB.
Kamar, K.A.M.,Alshawi,M. And Hamid,Z.,(2009). Barriers to Industrialised Building System (IBS): The Case of Malaysia. [pdf] United Kingdom: IPGRC. Available at: http://www.cream.com.my/publications/whitepapers/Abstract111.pdf. [Accessed 15 May2010]
Mohd Rofdzi Abdullah, Kamarul Anuar Mohd Kamar, Mohd Nasrun Mohd Nawi, Ahmad Tarmizi Haron, Mohammed Arif, (2009). Industrialised Building System: A Definition and Concept. [pdf] United Kingdom: ARCOM. Available at: http://www.cream.com.my/publications/whitepapers/Arcom.pdf. [Accessed 05 May 2010]
CHAPTER 2
LITERATURE REVIEW
2.0 Introduction
This chapter will explain in details and provide the literature review of Industrialised Building System (IBS). Besides that, it will also cover the literature review of building system. Usually, the contents of this chapter are including definitions of IBS, history of IBS in public housing, classification of IBS, types of IBS, characteristic of IBS, benefits and barriers of using IBS in public housing, IBS Roadmap 2003-2010 and IBS scoring system.
2.1 Definitions of IBS
Until the present time there has been no single commonly-approved definition of IBS. IBS can be different industry players to define different things. However, there are difference resources to define the several definitions that reflected the concept of IBS and which widely accepted by the construction industry.
According to CIDB Malaysia (2001) defines IBS as a construction technique in which components are manufactured in a controlled environment (on or off site), transported, positioned and assembled into a structure with minimal additional site works. As such, components that are being prefabricated in a controlled environment on site are also considered as IBS. While there are numerous descriptions of the IBS concept by local researchers, all of the definitions stressed on prefabrication and mass production.
In other definition by Warswaski (1999), the IBS can be defined in which all building are mass produced such as walls, slabs, beams, columns and staircases either in factory or at site factory under strict quality control and minimal wet site activities. Industrialisation process is an investment in equipment, facilities and technology with the purpose of maximising production output, minimizing labour requirement and improving total quality while a building system is defined as a set of interconnected element that joint together to enable the designated performance of a building.
Based on Lessing et al (2005) explained IBS as an integrated manufacturing and construction process with well planned organization for efficient management, preparation and control over resources used, activities and results supported by the used of highly developed components.
Rahman & Omar (2006) defined IBS as a construction system that is built using prefabricated components. The manufacturing of the components is systematically done using machine, formworks and other forms of mechanical equipment. The components are manufactured offsite and once completed will be delivered to construction sites for assembly and erection.
Chung & Kadir (2007) defined IBS as a mass production of building components either in factory or at site according to the specification with standard shape and dimensions and transport to the construction site to be re-arranged with certain standard to form a building.
2.2 History of IBS in Public Housing
IBS in Malaysia has began in early 1960’s, according to Thanoon et al (2003) when Ministry of Housing and Local Government of Malaysia visited several European countries, at the same time evaluates their housing development program. In the year 1964 and after their successful visit, the Government had launched pilot project on using IBS to increase the delivery time and to construct better quality and affordable houses.
The first pilot project was constructed at Jalan Pekeliling in Kuala Lumpur and about 22.7 acres of land was dedicated to the project comprising four blocks of 4-storey flats and seven blocks of 17-storey flats and comprising total about 3,000 units of low cost flats for the low and median income group and 40 units of shop lots. This housing project was undertaken by Gammon/ Larsen Nielsen and this project are using the Danish System of large panels in a industrialised prefabricated system. According to Thanoon et al (2003), the construction for housing project was complete from 1966 until 1968 (around total 27 months) speed up the time taken in the construction of the around RM 2.5 million casting yard at Jalan Damansara.
In 1965, the Government of Malaysia launched a second project, is a three blocks of 18-storey flats and six blocks of 17-storey flats and comprising total about 3,699 units and 66 units of shop lots along at Jalan Rifle Range in Penang. The housing project was honoured by Hochtief/ Chee Seng and this project are using French Estoit System (Din, 1984). This housing project was complete within 27 months.
If we are mention to the two pilot projects, a performance comparison between the IBS and the conventional system has been carried in terms of cost, productivity, quality, and time. According to the research, the first pilot project incurred 8.1% higher costs than a similar building such as using conventional construction method, while the second pilot project was lower. In term of total construction speed, both of the housing project required total 27 months to complete the whole project, inclusive of time required to set up the recasting factories. The total quality of building finishes was also found to be better than the using conventional construction method.
Another earliest using IBS in public housing project was at Taman Tun Sardon in Penang. These using IBS in public housing project total all about 1,000 units of 5-storey walk up flat and this project are using IBS precast component and system. The IBS precast component and system in the housing project was designed to the low cost housing by British Research Establishment and especially for the low and median income group. According to the research of Construction Industry Development Board Malaysia (CIDB) 2006, almost at the same time at Edmonton in North London, there are using similar system was constructed and total amount about 20,000 BRECAST dwellings were constructed throughout UK from 1964 until 1974. Based on Rahman and Omar (2006), the total all building design was very basic and quite simple and not considering the feature of serviceability such as the local or user needs to have wet toilet and bathroom.
According to the CIDB (2006), many constructions in the following years using precast wall panel system. Low cost high rise residential building is one of the processes to survey that IBS was connect at first place in the construction to overcome the increasing demand for housing needs. For all that, in the earlier stage was never sustained for the industrialisation of construction. Failure of early closed fabricated system made the industry afraid of changing their construction method. The information was based on the CIDB (2005), using IBS in construction were also found not be so suitable with Malaysia climate and social practices especially for the foreign systems that were introduced during the late 60s and 70s.
Introduced than in the construction market were constantly being newer and better technologies. Based on CIDB (2005), identified to be suitable to be used in our tropical climate is the wet joint systems and it was also better to using in the bathroom types which were comparatively wetter than those in the Europe.
Another about 1200 units of housing using prefabrication technology were is launched by the Penang State Government in 1978. After two years later, the Ministry of Defense to be build around 2800 units of living quarters and adopted large prefabricated panel construction system in Lumut Naval Base (Trikha and Ali, 2004).
Enhance the using of precast concrete system in high rise residential building during the 90s; this is because total demand for the new township has seen to increase. According to the research, Perbadaan Kemajuan Negari Selangor (PKNS) as a state Government development agency acquired precast concrete technology from Praton Haus International based on Germany to build low cost housing and high cost bungalows between 1981 and 1993 for the new townships in Selangor (Hassim et al, 2009 and National IBS Survey, 2003). It was recorded then; total around 52,000 housing units was constructed and using Praton Haus system.
In Malaysian construction industry, using IBS as a method of construction is evolving. Nowadays, more local manufacturers have established themselves in the market. Many had acquired enough knowledge through technology transfer to build up own capacity in IBS technologies and this research are base on PKNS Engineering, and Setia Precast and Global Globe.
The current stage of IBS used in Malaysia housing projects can be classified into four categories. It was reported that at least 21 manufactures and suppliers of IBS are actively promoting their systems in Malaysia. IBS move to the next step of the development through the establishment of IBS Centre at Jalan Chan Sow Lin, Cheras in Kuala Lumpur. Using IBS in the construction will improve the total performance and quality of construction, as well as to minimize the unskilled foreign labour in the construction industry.
2.3 Classification of Building System
There are four types of building system currently available in Malaysia’s building system classification and this are according to Badir – Razali (1998). The building system can be namely as a Conventional Column-beam- slab frame system with timber and plywood; Cast in-situ system with steel or aluminium as formwork; the Composite building system and Prefabricated system and this four types of building system is shown as below. Each building system is represented by its respective construction method which is further characterised by its construction technology, functional and geometrical configuration. There from the four systems, are identified as IBS excluding conventional building system.
Building System
Conventional Column-beam- slab frame system with timber and plywood.
Cast in-situ system with steel or aluminium as formwork.
Composite building system
Prefabricated system
Table Form
Tunnel Form
Panel system
Frame system
Box system
Flow Chart 1: Type of building system in Malaysia.
2.3.1 Conventional Construction Method
Conventional construction method is defined as components of the building that are prefabricated on site through the processes of timber or plywood formwork installation, steel reinforcement, and cast in-situ. This construction method is mostly built of reinforced concrete frames for conventional building. Using the wooden formwork mainly is for the traditional construction method and need take some time to construct the formwork before concreting. This construction method is much more costly for construction which is need includes total labour requirement, raw material, transportation and very importance once is low speed of construction.
2.3.2 Cast In-Situ Construction Method
This cast in-situ construction method is more suitable for a country where the unskilled labour is limited. There construction method is not a using heavy machinery or high technology involved. The system is technically and applicable to almost all types of building design. The formwork is used as a mould where wet concrete is poured into a temporary system and the temporary system also acts as a temporary support for the structures.
The main objective of a cast in-situ construction method is to weed out and reduce the using traditional timber formwork, brickwork, and plastering. A carefully planned in-situ work can maximise the productivity, speed and accuracy of prefabricated construction. Cast in-situ method uses lightweight prefabricated formwork made of steel or fibreglass or aluminium that is easily erected and dismantled. The steel reinforcement is placed within the formwork after finishes construct the formwork. After placing the reinforcement they are being erected and concrete is poured into the mould. When the concrete is set and according to the required strength, the moulds are dismantled. The workers can be easily trained to erect the moulds and set the steel reinforcement. These construction methods are required limited labour and it will reduce the total labour need. Its advantages over the conventional construction method include, low skill workers requirement, speedy construction, low building maintenance, durable structure and less construction cost.
2.3.3 Composite Construction Method
The main objectives of composite construction method or call partially prefabricated are to improve quality of components, reduce construction cost, and shorten total all construction time. It is used to describe a manufacturing or production strategy that selectively uses some industrialising aspects, while avoiding or postponing the use of others. The concept of composite construction method is derived from the composite nature of full industrialisation. The prefabricated construction method is combined in such a manner that the features applied could be prominently demonstrated, especially composing various works such as temporary facilities, building frames, building finishes, and equipments.
2.3.4 Prefabricated Construction Method
In this prefabricated construction method, all structural elements can be standardised are prefabricated in the factory. Usually, this construction method would absorb the assembly of precast elements such as floor slabs, in-filled walls, bathrooms, and staircases into place for incorporation into the main units, columns and beams. This construction method will increase the productivity of the industry and it will reduce the amount of site labour involved in building operations. Precast building systems can reduce the time of a project if certain conditions are met.
The last three construction methods (from the flow chart 1) are considered as a non conventional construction methods. These three types of construction method are specifically aimed at increasing performance of construction. Through using the better construction machinery, equipment, technology and materials and it will increase the productivity and total quality of work.
2.4 Classification of IBS
According to Badir et al. (1998), IBS can be classified according to several aspects:-
Classification according to structural system.
Classification according to material.
Classification according to relative weight of components.
2.4.1 Classification According to Structural System
According to Abraham Warszawski (1999), IBS can be classified according structural systematic aspects. The IBS can be classifies into three categories such as:-
Frame System.
Panel system.
Boxes system.
Figure 1, 2, and 3 below as shows the concept of the system as classified above.
Figure 2: Panel System
Figure 3: Box System
Figure : Frame System
2.4.1.1 Frame System
According to Badir (1998), linear and frame system is system that use main structure such as column and beam where columns and beams support all the building weight. The walls need to be light and easy to install and concrete panels are introduces as flooring element.
2.4.1.2 Panel System
According to Badir (1998), in the panel system, loads are distributed through large floor and wall panels where walls support the building weight. This system is applicable to buildings which functionally require a large number of walls such as apartment house, hotel and hospital. This system is not applicable to buildings with large spans or many stories. So, this panel system is more suitable to build the public housing in the certain high storey.
2.4.1.3 Box System
According to Badir (1998), the rectangular or three dimensional systems or boxes system include those systems that employ three dimensional modules or boxes for fabrication of habitable units that is capable of withstanding load from various directions due to their internal stability.
2.4.2 Classification According to Material
2.4.2.1 Timber
The timber have a two types of prefabrication which is ready-cut plus shop fabrication of joints this mostly for the columns and beams and another is structural panels where there are only for walls and floors without columns and beams.
2.4.2.2 Brick and Block work
Laying of brick or block work are carried out in a mass at factory and transported to site or on site construction. Besides the, building are under construction in the form of panel and then erected.
2.4.2.3 Steel
Steel construction essentially contains factors of prefabrication which is one of the criteria of IBS. Elements are jointed by welding, riveting or bolting on site. The large proportion of the strength to the weight allows a long-span or high-rise building.
2.4.2.4 Reinforced Concrete
There are two basic directions in development of reinforced concrete IBS component which is panelised components such as walls and floors and precast frame members such as columns and beams. The characteristic of reinforced concrete has high degree of availability, low material cost, durability, and fire resistance. Jointing at site is the key issue of this system.
2.4.3 Classification According to Relative Weight of Component
The IBS components can be classified according to their relative weight as show in Table 1 below. Relative to weight of components should be used as a basic for building classification due to the factor of weight has significant impact on the transportability of components and has influence on the production method of the components and their erection method on site.
No
General System
System
Production Material
1
Frame
System
Light weight frame
Wood, light gage metals
Medium light weight frame
Metal, reinforced plastics, laminated wood
Heavy weight frame
Heavy steel, concrete
2
Panel
system
Light and medium weight panel
Wood frame, metal frame
and composite material
Heavy weight panel
(factory produced)
Concrete
Heavy weight panel
(tilt up-produced on site)
Concrete
3
Box system
(modules)
Medium weight box
(mobile)
Wood frame, light gage
metal, composite
Medium weight box
(sectional)
Wood frame, light gage
metal, composite
Heavy weight box
(factory produced)
Concrete
Heavy box
(tunnel produced on site)
Concrete
Table 1: Building system classification according to relative weight of component. (Majzub, 1977)
2.5 Types of IBS and Apply to Public Housing
According to CIDB (2003), the IBS is a construction process that using techniques, products, components, or building system which involve prefabricated components and on-site installation. Base on the structure aspects of the system, IBS can be identified into five major groups such as:-
Precast Concrete Framing, Panel and Box Systems
Precast concrete elements are the most common type in this area. There are precast concrete for columns, beams, slabs, walls, lightweight precast concrete, and permanent concrete formwork. This all item are consider using precast method. Besides that, it is also consist of 3D components such as balconies, staircases, toilets, lift chamber, refuse chambers and etc.
This precast method is more famous for the construction industry, especially for the public housing when construct using the IBS. Using this method can saving the total construction time if compare to the conventional method.
Figure 4: Precast concrete wall
Steel Formwork Systems
This is the system formwork which designed by manufacturer to replace a conventional timber formwork. It can be described as a mould which the wet concrete can be poured into the mould and form the required shape.
These steel formworks systems are subjected to structural quality control and generally involve site casting. So, this type of IBS method is considered as the “low level” or “least prefabrication” in the construction industry. However, this steel formwork systems does offer fast construction and construction time saving and at the same time will provide high quality of finishes with less site labour and material requirement.
These steel formwork systems will include table forms, tunnel forms, tilt-up systems, beam and columns moulding forms and permanent steel formworks like metal decks and etc. This steel formwork system also one of the famous system used by the contractor during the construction.
Figure 5: Steel formwork system
Steel Framing Systems
These steel framing systems have always been the popular choice and used extensively in the fast track construction projects and this system commonly used with precast concrete slabs, steel columns and beams. Current stage of development in this type of IBS includes the increased usage of light steel trusses. It is consisting of cost-effective profiled cold-formed channels and steel portal frame systems as alternatives to the heavier traditional hot-rolled sections.
Nowadays, this method is more useful for the housing project, especially for the steel roof trusses (show as below figure 6). This is because the timber roof trusses need the labour to take some time to construct it and lastly need the anti-termite for the timber roof trusses.
Figure 6: Steel roof trusses
Prefabricated Timber Framing Systems
These prefabricated timber framing systems is using the timber in the construction industry for construct the building. Usually the timber framing system are consists of timber building frames and timber roof trusses (show as below figure 7). While the steel framing systems have been the more popular choice on construction industry, but the timber roof truss system also have its own market where it is offering interesting designs from simple dwelling units to buildings requiring high aesthetical values such as chalets for resorts. This prefabricated timber framing system we can see in the traditional building.
Figure 7: Prefabricated timber framing system for double storey house
Block Work Systems
By using this effective alternative system, the tedious and time-consuming traditional brick laying tasks are greatly simplified. The construction method of using conventional bricks has been revolutionized by the development and usage of interlocking concrete masonry units (CMU) and lightweight concrete blocks and etc. This is one of the more useful methods to construct the low cost public housing project.
Figure 8: Lightweight concrete blocks are used for wall construction
2.6 Characteristics of IBS for Public Housing
According to Warszawski (1999), the main features of an IBS are as follows:-
As many of the building elements are prefabricated off site, at a central facility, where specialized equipment and organization can be established for this purpose.
The various building works are incorporated into large prefabricated assemblies with minimum erection, jointing and finishing work on site.
Materials and component handling on site is extensively mechanized; in concrete work, large standard steel forms, ready-mixed concrete, and concrete pumps are used.
Design, production, and erection on site are strongly interrelated. They must be viewed therefore as parts of an integrated process which has to be planned and coordinated accordingly.
According to CIDB (2001), IBS has its own characteristics which are differ itself from conventional method. There characteristics of IBS are as follows:-
Industrial production of components though prefabrication; or highly mechanized in-situ processes.
Reduced labour requirement during prefabrication of components and site works.
Modern design and manufacturing methods which has the involvement of Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM).
Systematic Quality Control such as ISO 9000 principles.
Open Building concept where it is permitting hybrid applications, adaptable to standardization and Modular Coordination (MC).
2.7 Advantages of IBS for public housing
There are many advantages of implementing IBS. According to CIDB (2003), compares to conventional construction method. Following are brief descriptions on a number of advantages where using IBS for the public housing:-
Advantages
Description
Less total construction time
Using IBS will making the construction process faster.
Because casting of precast element at factory and foundation work at site can occur simultaneously and work at site is only the erection of IBS components.
So, the project can complete much earlier that using conventional method and handover to the owners.
Cost saving
Faster to the turnover of working capital and also save in the lifecycle costs of the finished buildings.
The formwork of IBS components are made of steel, aluminums or other materials that allows for repetitive use and this leads to considerable cost savings.
Using IBS will reduce the construction wastage and increasing the cost saving.
Saving in labour
Because the IBS components are produced in factory and higher degree of using machine so the use of labour will be reduced and lead to saving in labour cost.
According to Abraham Warszawski (1999), the labour savings in prefabricated elements may amount to about 80% of their conventional requirement.
So, will reduced the total foreign workers need in the construction industry.
Less labour at site
Using IBS will reduce the construction process at site and consequently reduce the number of labour required at site.
Using the IBS will saving of the labour in the masonry, plastering, formwork, tiling and pipe laying such as electrical and water supply at site.
Optimised use of materials
Using machine during the production of IBS components lead to higher degree of precision and accuracy in the production and consequently reduce material wastage.
So, the wastage at site will be reduced if using the IBS.
High quality and better finishes
Quality control is an ever-increasing requirement in all construction.
Due to the careful selection of materials and use advanced technology, so the IBS components will provide higher quality and better finishes.
Better quality control since production in factory is under sheltered environment.
Better quality will reduce the maintenance expenses because prefabricated components require less repair and preventive maintenance.
Construction operation less affected by weather
The effects of weather on construction operation are less due to the fabrication of IBS components is done in factory while at site is only erection of the components.
Faster project completion due to rapid all weather construction.
Flexibility
Different systems may produce their own unique prefabrication construction methods.
IBS will provide more flexibility in the design of precast element.
Increase site safety and neatness
This method will lead to the neater site condition and increase safety.
Using IBS components leads to less construction process especially for the wet work at site.
2.8 Disadvantages of IBS for Public Housing
Although there are a lot of advantages of IBS, however there are limitations for this system to be use too. Nothing in this world is perfect, so as using IBS. Disadvantages of IBS are as follows:-
Disadvantages
Description
High initial capital cost
The initial capital cost of IBS is usually higher than conventional method.
The initial cost is including the cost of constructing the factory, casting beds and support machinery.
This method only can be achieved when undertaking large demand for housing projects.
Problem of joints
These methods are very sensitive to the errors and sloppy work.
This joint problem will be the water leakage and is often the major problem in building constructed where using IBS.
This problem is clearer in Malaysia where raining occur rapidly throughout the year.
Sophisticated plants and skilled operators
The prefabrication system relies heavily on sophisticated plants, which have to be well coordinated and maintained by skilled operators.
Breakdown in any one section would hold-up the entire production line.
Site accessibility
Site accessibility is one of the most important factors of the implementation of IBS.
IBS requires adequate site accessibility to transport IBS components from factory to the site.
According to Abraham Warszawski (1999), the transportations cost of prefabricated elements from plant to their construction site, amount to 3% to 5% of their total cost for distances not exceeding 50km to 100km.
Large working area
Building construction using IBS requires a large working area for the factory, trailers, tower-cranes and storage for the IBS components.
Most construction sites especially in cities are often congested and unable to provide the area required.
Hence, prefabrication is at disadvantage when asked to complete for work at locations far from the fabrication yard. Table 2 shows as the relative advantages and disadvantages of industrialization under various conditions.
Table 2: Relative advantages and disadvantage of industrialization under various conditions.
2.9 IBS Roadmap 2003-2010
Prefabricated construction in Malaysia started way back almost fourth years ago with the completion of the Tunku Abdul Rahman Public Housing Estate or commonly known as the Pekeliling Flats. No proper plan was formulated by the government for the industrialisation of construction and until the inception of the IBS Roadmap 2003-2010. This is a master plan to facilitate the transformation the Malaysian construction sector was formulated with inputs from industry and endorsed by the Cabinet back in October 2003. Known as the “Industrialised Building System (IBS) Roadmap 2003-2010”, the master plan is based on the 5-M Strategy (Manpower, Materials-Components-Machines, Management-Processes-Methods, Monetary economic and financial and Marketing promotion) with the aim of having an industrialised construction industry as well as achieving Open Building by the year 2010. The transformation of the construction sector is crucial in ensuring the successful achievement of Vision 2020.
The objectives of IBS Roadmap’s 2003-2010 are:-
To reduce the percentages of foreign workers from the current stage is 75% to 55% in 2005, 25% for 2007 and 15% for 2009.
Increasing the percentages of using IBS for the Government Building Project from the 30% to 50% for 2006 and 70% for 2008.
To increasing the quality, productivity, safety and competitiveness in the construction sector.
To reduce the total percentages of foreign workers especially involved in wet trades.
Using modular co-ordination (MC) based on MS 1064 through Undang-undang Kecil Bangunan Seragam (UKBS).
Based on the IBS Roadmap 2003-2010, positive impacts from the fundamental proposal and new government incentives are:-
The industry will choose IBS which guarantees better quality, productivity and safety.
The enforcement of using Modular Coordination (MC) through Uniform Building By Laws (UBBL) will encourage standardization and increase the usage of IBS components. It also encourages participation from manufacturers and assemblers, especially Bumiputera, to go through the market, therefore reducing the price of IBS components. MC will facilitate open industrialization.
Selection program based on IBS standard components will ensure that low quality products are not marketed in the country and this will prevents the dumping of foreign IBS products in Malaysia.
By reducing wet trades through IBS, the dependency on foreign workers will also reduce, thus gaining the billions of Ringgit currently being transferred out by the foreign workers to their home countries and reducing inherent social problems involving these foreign workers.
2.10 IBS Content Scoring System (IBS Score)
As a regulatory requirements such as “minimum percentage of using IBS in government building projects” and encouragements such as “CIDB Levy exemptions for a minimum percentage IBS are using” have been put forward, a system for IBS content assessment is needed.
The IBS Content Scoring System (IBS Score) is a systematic and structured assessment system that can be used to measure the usage of Industrialised Building Systems (IBS) in a consistent way. The IBS Scoring System emphasizes on the following attributes:
The use of prefabricated and precast components.
Off site production of components.
The use standardised components.
Repeatability.
Design using Modular Coordination concept.
The maximum of IBS Score for a building is 100 points. The IBS Score is made up of 3 parts, which are:-
Part (1)
Structural Systems which to contribute maximum 50 points from the overall project.
Part (2)
Wall Systems, the maximum score for this part is 20 points.
Part (3)
Other Simplified Construction Solutions, which is contributing maximum 30 points from the overall project.
Table 3: 3 Parts of IBS Score
Each part on the IBS Scoring was having their own rules and regulation to calculate the points. For example: under Part (1): Structural System, the points are awarded for various types of structural system used such as precast concrete beams and columns, steel, and prefabricated timber. For the Part (2): Wall Systems, the points are awarded based on various types of wall systems used such as precast concrete panel, glass, dry partition and block work. For the Part (3): Other Simplified Construction Solutions, the points are awarded based on usage of other simplified construction solution for example standard components based on MS 1064, standardized grids, other 3D prefabricated components (prefabricated toilets, and staircases). IBS Score calculation only considers the superstructure elements of a building and sub-structure works are not taken into account in the calculation.
Higher IBS Score is reflections of a more reduction of site labour requirement, lower wastage at site, provide cleaner environment, better quality control, neater and safer construction sites, faster project completion as well as lower total construction costs. The detail information about IBS Score, methods of calculating IBS Score as well as sample calculation are included in Manual for IBS Content Scoring System (IBS Score) published by CIDB.
According to IBS INFO by CIDB (April to Jun 2010), increasing of quality components in the construction industry from time to time are responsibility by the IBS Central. Based on the IBS Central 2010 survey, total all production from industry has 122. While the total number of components under IBS products are 287. In addition, the precast concrete systems are more famous or useful within this 3 months and total number of components under IBS products are 97.
Table 4: Production and IBS products (2010)
Chart 1: Production and IBS products (2010)
In 2010, the IBS Central has received the total amount 217 consultants are registered under CIDB. Based on the table 5 below, the total amounts of the Engineers are higher than other is 131 people, while the Architect is 48 people and Quantity Surveyor is 38 people. All of the 217 consultants will be list in the Orange Book and publications by the IBS Central. This listing of consultants has been taking training conducted by CIDB and the three modules in the training such as IBS01, IBS02, and IBS03.
Table 5: Total Consultants are registered under CIDB (2010)
Chart 2: Total Consultants are registered under CIDB (2010)
For the total number of IBS Contractors in 2010 is 678 and all of the Contractors must taking the courses offered by CIDB. The courses offer by the CIDB is B01 (Building and Industrial Precast concrete Work), B02 (Building and Industrial Steel Structure Work), and B19 (Special Framework). The popular of the each course for Contractor are list in table 6 below: