The main aim of this research work is to compare the factors affecting cost of industrialized building and conventional building system in Nigeria. The research method used in collecting data was through the use of questionnaire administered to construction professionals in Nigerian construction industry. Seventy questionnaires were administered and fifty five were returned with response rate of 73%. The instrument used in analyzing data collected was relative importance index (RI!) to rank the factors affecting the two systems in Nigeria. From the analysis it was discovered that the major factors affecting cost of industrialized building and conventional building system in Nigeria were unstable government policy, inadequate manufacturing facilities, high cost of overhead, availability of expertise, scope of work, suitable construction environment, bureaucracy, materials waste, high cost of construction, availability of land with relative importance index of 0.82, 0.8, 0.79, 0.78, 0.77, 0.76 respectively. It was recommended that government should help in reducing the cost of building components, materials, plants and equipment and they should also set an example of patronizing the industrialized building system just as conventional building system and they should not be too strict in policy making. In conclusion the major factors affecting cost of industrialized building and conventional building system in Nigeria were unstable government policy, inadequate manufacturing facilities, high cost of overhead, availability of expertise, scope of work, suitable construction environment, high cost of construction, availability of land respectively.
1.1 Background of the study
Construction system is undergoing a translational change from a construction industry employing conventional construction to a more modernized and advanced system. Like a pre-fabricated component system, steel framing system, block work and mould system and timber framing system in all such system is known as industrialized building system (IBS).In this new technique of construction in order to increase the productivity of construction and improve quality of work. The system can be used good construction, equipment, materials and better project planning. This study is present and defined actual difference between conventional and industrialized building system, which can provide the necessary information on the building cost comparison between the two systems. This study also addresses the building cost comparison, more advantages and effective in between the two systems. Such provides the details building cost indicates which of the two are cheaper.
Conventional building method is defined as components of the building that are pre-fabricated on site through the processes or timber/plywood formwork installation, steel reinforcement and cast institute. Conventional building is mostly built of reinforced concrete frames. The traditional construction method uses wooden formwork. It is much more costly for construction which includes labour, raw material, transportation and low speed of construction time.
Industrialized building system is an advancement of the new construction technology in the Nigerian construction industry of today. It is an alternative of construction that can change many aspects in building construction. The industrialized building system is a construction system that is built using prefabricated components and 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. It is also can be interpreted as a system which components is manufactured in factory and then installed on site based on the size and dimension of the component required. Furthermore, systems in which concrete components prefabricated at site or in factory are assemble to form the structure with minimum in situ concrete.
Currently, the industrialized building and conventional building system in Nigeria has gradually widely used as a modern method of construction. As an example, the industrialized building system (IBS) and conventional building system has been applied in several projects such as Coca-Cola industry in FCT Abuja, Benue brewery industry in Benue state and Benue Cement Company in Yandev Gboko Federal Housing Authority Lugbe, Mass Housing Construction FCT Abuja, and residential building in FCT Abuja etc. The implementation of industrialized building system (IBS) and conventional building system in Nigeria is reducing the entrance of foreign labour and to expedite the progress of the construction.
The common types of industrialized building system which are generally used in construction are pre-cast concrete framing, panel and box systems, steel formwork system, steel framing system, prefabricated timber framing system, and block work system.
Industrialized building system (IBS) has proven that it can contribute many advantages in construction project. The industrialized building system (IBS) can reduce the number of unskilled and foreign workers on site. The presence of them can increase cost and wastage in construction industry.
1.2 Statement of the Problem
ABDULAZIZ (2002) stated that the cost of industrialized building system for medium and most low rise housing has been higher than that of traditional /conventional built dwelling though the shells were erected more quickly. Hence there is higher cost in industrialized building compared with conventional buildings it becomes comparative that the factor affecting the two building system must be accessed to proffer solution for the cost of industrialized building and conventional building system.
1.3 The need for the research
The need for this research is to critically compare and accessed the factors which directly or indirectly affect the cost of industrialized building system, and conventional building system and see if they could be controlled or avoided completely.
1.4 Aim and Objective
This research aims at assessing the factors affecting the cost of industrialized building and conventional building system and to identify ways in which these factors can be controlled.
1.5 Scope and Limitation of the Study
The scope of this project work is based on the comparative assessment of factors affecting cost of industrialized building and conventional building system in Nigeria.
It has not been possible to conduct this research nationwide due to the limited time but the research only carried out in Federal capital territory Abuja and Benue state.