ABSTRACT

Cost estimating is a key activity in quantity surveying profession and in contractor's organisation. The research work is to investigate into current cost estimation practices of contractors in Akwa Ibom state. The objectives were to identify the techniques used in cost estimating by the construction contractors, identify the causes of inaccuracy in construction contractors cost estimates and determine cost estimating risks influencing construction project estimates. Relevant literature on current cost estimating practices of construction contractors were reviewed and an exploratory field survey was undertaken to examine the objectives of the study. A total of 159 questionnaires were distributed to construction contractors, of which 127 completed questionnaires were returned, representing a 81.41% response rate. The data obtained from field survey was analysed using mean item score. The study shows that group decision making, expert judgment and reserve analysis are the most frequently used technique of construction cost estimating employed by contractor. The major causes of inaccuracy in cost estimating are unforeseen change in prices of materials, Lack of experience on similar project and instability of market condition. The result also shows that the major risk factors in construction cost estimating include variations in labour productivity data, estimator’s deficiency and error in design and specification. The study recommends that construction contractors and estimators should ensure that a frequent market survey are done for material and labour before estimating is done.

TABLE OF CONTENT

Title page        …        …        …        …        …        …        …        …        …        i

Approval Page            …        …        …        …        …        …        …        …        …        ii

Certification    …        …        …        …        …        …        …        …        …        iii

Dedication      …        …        …        …        …        …        …        …        …        iv

Acknowledgement      …        …        …        …        …        …        …        …        v

Abstract          …        …        …        …        …        …        …        …        …        vi

Table of Content         …        …        …        …        …        …        …        …        vii

List of Table    …        …        …        …        …        …        …        …        …        xi

CHAPTER ONE:  INTRODUCTION

1.1       Background to the Study       …        …        …        …        …        …        1

1.2       Statement of Problem                        …        …        …        …        …        …        2

1.3       Research Question     …        …        …        …        …        …        …        3

1.4       Aims and Objectives   …        …        …        …        …        …        …        4

1.5       Significance of the Study       …        …        …        …        …        …        4

1.6       Scope of Study           …        …        …        …        …        …        …        5

CHAPTER TWO: LITERATURE REVIEW

2.1       Definition of Cost Estimating            …        …        …        …        …        …        6

2.2       Scope of Cost Estimating      …        …        …        …        …        …        8

2.3       Purpose of Cost Estimating   …        …        …        …        …        …        9

2.4       Types of Estimate       …        …        …        …        …        …        …        9

2.4.1    The Approximate Estimates    …        …        …        …        …        …        10

2.4.2    Detailed Estimates      …        …        …        …        …        …        …        10

2.5       Qualities of a good cost estimate        …        …        …        …        …        11

2.5.1    Estimator skill …        …        …        …        …        …        …        …        13

2.5.2    Estimator Responsibility         …        …        …        …        …        …        14

2.6       Cost Estimation Techniques for Project         …        …        …        …        14

2.6.1    Expert Judgment         …        …        …        …        …        …        …        15

2.6.2    Parametric Estimate    …        …        …        …        …        …        …        15

2.6.3    Analogous Estimate    …        …        …        …        …        …        …        16

2.6.4    Three Point Estimating           …        …        …        …        …        …        16

2.6.5    Bottom-up Estimating            …        …        …        …        …        …        …        17

2.6.6    Reserve Analysis         …        …        …        …        …        …        …        17

2.6.7    Vendor Bid Analysis  …        …        …        …        …        …        …        18

2.6.8    Project Management Estimating Software     …        …        …        …        18

2.6.9    Cost of Quality (COQ)           …        …        …        …        …        …        19

2.6.10  Group Decision making Techniques  …        …        …        …        …        19

2.7       Accuracy of Cost Estimates   …        …        …        …        …        …        19

2.8       Factors Affecting the Accuracy of Cost Estimating  …        …        …        20

2.8.1    Error in Judgment       …        …        …        …        …        …        …        20

2.8.2    Insufficient Time for estimating         …        …        …        …        …        21

2.8.3    Lack of Experience on similar project            …        …        …        …        21

2.8.4    Unforeseen change in prices of materials       …        …        …        …        21

2.8.5    Instability of Market condition           …        …        …        …        …        21

2.8.6    Design Complexity     …        …        …        …        …        …        …        22

2.8.7    Assumptions/guess work        …        …        …        …        …        …        22

2.8.8    Lack of Historical Data from similar project  …        …        …        …        22

2.8.9    Incomplete project scope Definition   …        …        …        …        …        22

2.8.10  Incomplete Design and Specification …        …        …        …        …        23

2.8.11  Unavailability of Design Information …        …        …        …        …        23

2.9       Risk Factors in Construction Estimates          …        …        …        …        23

2.10     Cost Estimate Risk     …        …        …        …        …        …        …        26

2.11     Sources of Risk in Construction Projects       …        …        …        …        26

2.12     Summary of Review   …        …        …        …        …        …        …        27

CHAPTER THREE: RESEARCH METHODOLOGY

3.1       Research Strategy       …        …        …        …        …        …        …        28

3.2       Research Design         …        …        …        …        …        …        …        28

3.3       Area of the Study       …        …        …        …        …        …        …        29

3.4       Population of the Study         …        …        …        …        …        …        29

3.5       Sample Size and Sampling Techniques          …        …        …        …        30

3.6       Data Collection Method        …        …        …        …        …        …        30

3.6.1    Questionnaire …        …        …        …        …        …        …        …        31

3.7       Method of data analysis         …        …        …        …        …        …        31

3.7.1    Mean Score Index       …        …        …        …        …        …        …        31

CHAPTER FOUR: DATA ANALYSIS AND INTERPRETATIONS

4.1       Questionnaire distribution Analysis    …        …        …        …        …        33

4.2       Respondents Characteristics   …        …        …        …        …        …        33

4.3       Presentation and Analysis of Questionnaire   …        …        …        …        36

4.4       Summary of Findings …        …        …