CHAPTERONE
1.0 Introduction
1.1 Background to the Study
Construction estimation is an experience-based process (Elhag et al., 2005). The code of estimating practice produced by the Chartered Institute of Building (CIOB, 1997) defined estimating as “the technical process or function undertaken to assess and predict the total cost of executing an item(s) of work in a given time using all available project information and resources. Based on this definition, estimators‟ estimated cost is based on the time of construction or project duration, cost of material, method of construction etc. and estimators are aware that most of these factors can be readily estimated. The estimators in the construction team are usually the Quantity surveyors. The Quantity surveyor as an expert is employed early enough in the project so as to advice the client/Architect on the probable cost implications of the design decisions and to assist in obtaining economical and efficient design (Seeley, 1996) However, experts in construction estimation are aware of uncertainty, incompleteness and unknown circumstances of factors affecting cost of construction. As a result of various studies, several estimating techniques have been exploited and several models have been developed (Elinwa and Buba 1993; Elhag and Baussabaine, 1998;Dissanayaka and Kumaraswamy, 1999; Munns and Al-Haimus, 19992000; Ashworth, 2002;Ganiyu and Zubairu, 2010) but the limitation of these techniques and models is that they failto account for the effects of the factors that are more qualitative in nature.
2
The cost of construction in Nigeria has been reported to be high(Olatunji, 2010), and this has been attributed to several cost determinant variables.Olatunji (2010) reportedthat construction cost in Nigeria are often high and unpredictable and the pattern of the variability is not explained by inflationary indices of common goods and services but rather it is reactive to boom-and-burst shocks that are triggered by the oil price regimes. Elhaget al. (2005) identified and evaluated cost determinant variables within the UK construction industry among Quantity surveyors. Prior to the study carried out by Elhaget al. (2005), Okpala and Anekwu (1988) argued that underdeveloped economies tend to exert different influences on construction cost compared to developed economies such as the UK. This has a major impact upon critical determinants of construction tender sum. Windapo and Iyagba (2007) stated that the Nigerian construction industry need to map out efficient strategy for determining efficient determinants of construction cost in Nigeria, given the peculiar dynamics of the cost of finance.
1.2 Statement of the Problem
The identification of cost – determinant variables and evaluation of the degree of influence of these factorson construction cost estimates play an essential role in the building up of reliable cost estimates and enhance the competitive edge of quantity surveyors as well as the contracting organization. Elhaget al. (2005) identifiedand evaluated cost determinant variablesto
1.0 Introduction
1.1 Background to the Study
Construction estimation is an experience-based process (Elhag et al., 2005). The code of estimating practice produced by the Chartered Institute of Building (CIOB, 1997) defined estimating as “the technical process or function undertaken to assess and predict the total cost of executing an item(s) of work in a given time using all available project information and resources. Based on this definition, estimators‟ estimated cost is based on the time of construction or project duration, cost of material, method of construction etc. and estimators are aware that most of these factors can be readily estimated. The estimators in the construction team are usually the Quantity surveyors. The Quantity surveyor as an expert is employed early enough in the project so as to advice the client/Architect on the probable cost implications of the design decisions and to assist in obtaining economical and efficient design (Seeley, 1996) However, experts in construction estimation are aware of uncertainty, incompleteness and unknown circumstances of factors affecting cost of construction. As a result of various studies, several estimating techniques have been exploited and several models have been developed (Elinwa and Buba 1993; Elhag and Baussabaine, 1998;Dissanayaka and Kumaraswamy, 1999; Munns and Al-Haimus, 19992000; Ashworth, 2002;Ganiyu and Zubairu, 2010) but the limitation of these techniques and models is that they failto account for the effects of the factors that are more qualitative in nature.
2
The cost of construction in Nigeria has been reported to be high(Olatunji, 2010), and this has been attributed to several cost determinant variables.Olatunji (2010) reportedthat construction cost in Nigeria are often high and unpredictable and the pattern of the variability is not explained by inflationary indices of common goods and services but rather it is reactive to boom-and-burst shocks that are triggered by the oil price regimes. Elhaget al. (2005) identified and evaluated cost determinant variables within the UK construction industry among Quantity surveyors. Prior to the study carried out by Elhaget al. (2005), Okpala and Anekwu (1988) argued that underdeveloped economies tend to exert different influences on construction cost compared to developed economies such as the UK. This has a major impact upon critical determinants of construction tender sum. Windapo and Iyagba (2007) stated that the Nigerian construction industry need to map out efficient strategy for determining efficient determinants of construction cost in Nigeria, given the peculiar dynamics of the cost of finance.
1.2 Statement of the Problem
The identification of cost – determinant variables and evaluation of the degree of influence of these factorson construction cost estimates play an essential role in the building up of reliable cost estimates and enhance the competitive edge of quantity surveyors as well as the contracting organization. Elhaget al. (2005) identifiedand evaluated cost determinant variablesto
