Q.
What are the basic features and limitations of IBS and what are their obstacles in implementation?
A.
Read about
Classification and Types of IBS;
Definition and Benefits of IBS;
Features and Challenges of IBS (this posting); and
Barrier to the implementation of IBS
Basic features of IBS
Closed System - which means specific product for specific use only
Warszawski (1999) stated that the production based on pre-caster's design includes designing and producing a uniform type of building or a group of building components, which can be produced with common assortments of component. Nevertheless these types of building arrangement can be justified economically only when the following circumstances are observed.
1. The size of project is large enough to allow for distribution of design and production costs over the extra cost per component incur due to the specific design.
2. The architectural design observes large repetitive element and standardisation. In respect to this, a novel prefabrication system can overcome the requirement of many standardised elements by automating the design and production process.
3. There is a sufficient demand for a typical type of building such as school so that a mass production can be obtained.
4. There is an intensive marketing strategy by pre-caster to enlighten the clients and designer the potential benefit of the system in term of economics and noneconomic aspects.
Open Building System (OBS) - which means products can be used in other designs or conditions
This system enables openness in its structure supplier where everybody can bid to produce lower price. In addition, the pre-caster and erectors will look for cooperation models that will create win-win situation for both parties. Thanoon et al (2003) added that OBS provides a high degree of design flexibility, which required a maximum coordination between the designer and pre-caster.
In spite of many advantages inherent in OBS, its adoption experiences are one of the major setbacks. For example, joint and connection problem occur when two elements from different system are fixed together. This is because similar connection technology must be observed in order to achieve greater structural performance.
The Modular Coordination - an attempt to standardize the specifies by being modular
The modular co-ordination for building component apply the basic length unit or module of M = 100 cm. This allows the designer to apply this size or its multiple in the production of building components. Although this concept seems to be easy for adoption, its application involves a great degree of coordination and adjustment in the manufacturing process and the interfacing aspects of components.
Mass Production
The investment in equipment, human resources, and facilities that related with IBS can only be considered economical when there is large quantity of production. Such volume can provides a distribution of the fixed investment charge over a large number of product units without excessively increasing their ultimate cost (CIDB Singapore, 1992).
Specialisation
Warszawski (1999) mentioned that large production output and standardisation of precast elements enables a high degree of labour specialisation with the production process. These processes can be divided into a large number of small homogenous tasks. In such working condition, workers are exposed to their work repetitiously that would pose higher productivity level.
Good Organisation
High production volume, specialisation of work, and centralisation of production requires an efficient and experiences organisation (Warszawski, 1999). A good organisation should capable of a high level of planning, organising, coordinating and controlling function with respect to production and distribution of IBS products.
Integration, Planning and Control of the Processes
In order to obtain an optimal result, Warszawski (1999) pointed out that a high degree of coordination must exist between various relevant parties such as designer, manufacture, owner and contractor. This is achieved through integrated system in which all these functions are performed under unified authority.
The design, manufacture, assembly and other related process requires a coherent structure and management from the start to the end in order to reach the goal and deliver a maximum value to the customers. A thorough planning of all activities is required especially in the early stage of projects where extra attention must be paid to design in aspect of architectural as well as engineering, planning and preparation.
Production Facility
Peng (1986) pointed out that the initial capital investment for setting up a permanent factory is depending on experience. Plant, equipment, skilled worker, management resources need to be acquired before production can be commenced. The investment can only be levelled if there is sufficient demand for the IBS products. From the other point of view, temporary casting yard or factory can be established at the project site in order to minimise the transportation costs.
Transportation
Peng (1986) found out that casting of large-panel system can reduce labour cost up to 30 percent. However, these cost savings are countered by the transportation costs. The transportation of large panels is also subject to the country‟s road department requirement. These limitations must be taken into consideration when adopting a prefabrication system.
Equipment on Site
For the purpose of erecting and assembling precast panels into their position, heavy crane is required especially for multi-storey building. It is therefore important to incorporate this additional cost when adopting a prefabrication system.
The usage of IBS would reduce substantial amount of unskilled and skilled labourers that are involved directly on site. This has been proven according to Warszawski (1999) whereby a study was carried out in Israel to compare between IBS and conventional construction method in 1984. The results shows that the use of IBS has brought much saving in site labour up to 70 percent and saving on total construction cost if compared to the conventional methods. Correspondently in Singapore, the research conducted by Cheong (1997) shows that the use of fully prefabricated system provides labour saving up to 46.5 percent as compared to the conventional method. This would decrease on the dependency of foreign labour workers. However this does not affect the country workforce. The usage of IBS will open up many opportunities to the younger generations that seem to be reluctant to be involved in the construction industry.
Limitations and Obstacles
The manufacturing of industrialised process of IBS need to be studied very thoroughly so that it can meet the current local needs in terms of speed, quality and cost saving. The standardisation of the manufacturing process through the modularization of components can increase product variety without seriously affecting the production cost. The standardization of manufacturing process enables it to be accepted for the implementation of IBS.
[It is in fact like setting up a website, the whole lot of the navigation of the website is like IBS. The navigation links must be well thought-out before the site is developed. The links from one topic or page to another and sub-links within the website require careful planning and execution.
So, it is a system. Within this system, the front and the back - meaning what to come earlier and later, are supported on a platform of specific design called modular coordination which ensures usability and efficiency in technology, both hardware and software.
There are prerequisites for this modular coordination. Hence, situation not conforming to this modular coordination cannot be assimilated into the system. Example, the parts are built to a specification in the factory and transported to the construction site to be assembled. The tools and technology of the assembly require certain standards. This includes technology standards and skilled execution. In short, there are steps to take – one before another in a proper sequence. A glass panel which needs to be fitted would need holes or edges cut through the glass. These holes can only be drilled in the factory. Hence, transporting the glass with the holes wrongly placed would render the glass unable to be fitted on site.
It is both impossible and not feasible to drill the holes on site due to the immense cost of bringing the glass driller machine to site. Moreover, it might be just a few piece of glasses which requires this fitting. Thus, it is not economical to relocate the glass factory to just cater for this work. Just like building a website, there are certain steps to take to deploy the pages and later, link them together. The linkage and types of storage files, especially their formats and file sizes would very much depend on the software and hardware running the website/servers. Any of the mistake or inconsistency in this would render the website defective. Same is for IBS in this analogy.
The success of IBS would depend largely on its flawless execution, and its economics of scale. In the luxury of cheap labour, without these two key success factors, IBS would not be feasible. The poor execution would result in wastage, hence not achieving the saving which IBS is supposed to accomplish. On the same note, building a small project would not benefit much by going into the trouble of implementing IBS. Just like designing a three pages leaflet does not require the use of highly professional software like Adobe Illustrator, rather it could be well accomplished by using just Microsoft PowerPoint.
The much systemized processes, and execution of IBS may be a long learning curve for workers.
Despite the benefit of time saving, it might be cumbersome and time consuming initially for the workers to learn the rope. This may impair the other benefits of IBS like time saving, cost saving and reduction of wastage. As a whole, young and small enterprises may in fact be unsuitable for implementing IBS due to multiple learning difficulties. This includes limited staffing or lack of economics of scale to execute the more skilled construction techniques, which is the basis of IBS.]
Ref:
Kamarul Anuar Mohamad Kamar, Mustafa Alshawi and Zuhairi Abd Hamid (2009), Barriers to Industrialised Building Systems: The Case of Malaysia, paper proceedings in BuHu 9th International Postgraduate Research Conference (IPGRC 2009), The University of Salford, 29 – 30th January, 2009, Salford, United Kingdom.
Kong, Xi Haw (2009) Barriers in the implementation of industralized building system in Malaysian construction industry. Degree of Master of Science (Construction Management), UTM, available at
http://eprints.utm.my/11343/
[x] Own account.