Finalyear

CHAPTER ONE
1.0 INTRODUCTION
1.1 BACKGROUND OF THE STUDY
A roof is the uppermost part of a building, whose main function is to enclose the space and to protect same from the effects of weather element such as: rain, wind, sun and heat. A good roof is just an essential as a safe foundation. As a well design foundation secure the building against distributions starting from or at the bottom, similar a good roof should satisfy the following functional requirements such as durability, resistance to moisture thermal insulation and safety from fine in the deign and construction in other to afford protection to the building itself and what the building contains and power deterioration starting from the top\.l roofing materials, are exposed to the element of weather namely, wind, sunlight, rain hail, atmosphere pollution an well an temperature variation of consequently degrade over time
Different type of materials and technologies are available for building design and construction, which new materials and advanced technology are continuously being introduced into the market. All of there materials have their advantages and disadvantages, so the task of choosing the optimal option in complex and requires special method to eliminate the subjectivity of evaluation. Although, material are generally selected from the existing category of material and traditionally expert apply trial and error method use experience to choose new materials that have better performance modern architecture has given rise to different methods of roof design and construction, and hence roof types. All roofs can be broadly classified into two types on the basis of slope; flat and picture roofs. Roofs having pitched not exceeding 100 are defined as flat while for higher pitch , they are represent to an “pitched”.
The desirability for a roof over a building in a old as mankind. Modder (2012), reported that the desirability for a roof to offer protection was possible for early man’s preference to time in cares and hollow – these even when in safety might be threatened thus, cares served a natural protective cover for regulating environmental factors in the early open. Modern man late developed an artificial protective cover; the Bamboo roof and thatch roof made of direct straw and reach were the first set of there artificial roofs that came into existence. Improvement in technology has resulted in the development of asserted materials for roof construction including wood, content metal, rubber, lime stone, clay and ceramics
Roof are sunceptile to wealth effect and failure. A roof is said to have failure if it is a number longer capable of performing any of its desired functions and such failure s could be either structural of thermal. The ultimate and more easily notices types of structural or thermal. The ultimate and more early noticeable type of structural failure could be either structural or thermal failure manifest itself flow the atmosphere to the building. The performance of a roof in Manuel base on its life span and the effectiveness of it components to retain their strength, chemical and physical properties appearance and rain force to all form of failure. Most of failure occur at both connections that were either inadequately secured of the time of construction or that have since failure due to deterioration. Many roof designed often fail to take into account a number of design factors such as tolerance and factors of safety, and these coulf failure. Other factors that could causes failure in too failure in roof are the effect of wind as earlier said, fire outbreak , poor workmanship , apa poor maintenance etc.
The impact of selecting roof materials (covering) an affect the durability, functions and quality of the product because it contribute to the safety and health of the end – users (Chan and Tony, 2007).
The designer ]needs the appropriate information to compare materials with the requirement ((Van Kersteven, 2008) and they have to find all information from different source. The client want to overall cost of the construction (Mohammed and Celikl, 1998). And their houses according to their requirement and within the budget. Moreover, they demand hight quality building with life time cost effectiveness (Schale, 2007). It is true that roof covering have significant impact on the cost of a building, if properly selected (quality) may reduce the maintenance cost. It in a complex to select the suitable material for roof professional in the construction section to select the appropriate material according to the desired needs.
1.2 STATEMENT OF THE PROBLEM
There is a knowledge gap in the selection of requirement on the literia ranging from initial cost and durability to zero carbon foot prints and sustainability and cost estimation. In order to fill the gap, it require the ability to simultaneously evaluate multiple criteria in the optimization of material selction for building. Based on the fact sta6ed above, this research work seeks to evaluate the factors that influence the choice of roof covering in commercial building project. Roof covering materials is a very important components of a building. This is partly because it servers other components of the building and its occupant of the element of weather faults, roof covering material in severe, and as such, it is very important/paramount to consider certain factors in order to make good choice when selecting roof covering material.
1.3 AIM AND OBJECTIVES
The aim of this study is to evaluate the factors influencing the choice of roof covering material in commercial building. To achieve the control aim stated above, a number of objective have being set such as:
1. To identify the various types of roof covering in the construction industry.