Friday, November 15, 2019
Quality Assurance in Construction Projects
Quality Assurance in Construction Projects ABSTRACT: The main aim of this research is to let readers know how useful quality assurance is and its benefit to the community. To guide construction industries on how they can assure quality in their constructions and also how building industry to can achieve minimum loses and avoid risk on site. Furthermore, to also let contractors satisfy the need of their clients. KEY WORDS: Quality assurance, implementation, improvement, effectiveness and comparison. INTRODUCTION: The main motive behind this research is to produce a reliable source to identify the need for Quality Assurance in Design (Construction). Statistics has revered that lot of problems facing construction work is due to the fact that, Quality is not assured in construction. In my point of view, quality assurance can be done if we avoid all the following problems: Poor coordination of subcontractors work, unable to supervise and verification on site, lack of communication among architects, engineer, subcontractors and material supplies, uncertain instructions and unqualified operators and also misinterpretation of drawings and specification. As a matter of fact these problems can cause frequent delay in project, financial loss in companies and loss of confidence in contractors as result of inefficient quality assurance. A project lacking all these effects could end up as indication in fig 1.1. See below how the demonstration of a good quality assurance project and non quality assured project could be. As you can see from the diagram illustration, the red line explains the stability of a construction with good quality, however it also means that, the construction will not face any problems in some years to come. Whereas, the blue line indicate how a building can be of no quality and as a matter of fact, it is possible for the building to collapse in a short period of time. I have therefore decided to research on the subject as I believe that construction industry could improve upon it performance if the above mentioned is avoided so that construction would be quality assured. Besides, since construction work is team work and all members need to contribute to its effectiveness and quality of the construction, therefore this will allow the members of the project team to identify the main objectives of quality in a project. In order to achieve this, it is better to establish a technique for modeling the relationships between the project environments, objectives, control systems and feedback in the construction process. In this case the purpose will make recommendations to clients of the construction industry and their advisers and about how to make sure projects are quality controlled and assured. PROBLEM FORMULATION Quality Assurance is one of the major areas in construction in which much attention must be drawn into. As a result of this, it is my duty to figure out how quality can be assured in the construction industry. Generally speaking, there has been complains, delayance and financial losses in construction companies due to lack of quality in the construction industry. Again, if a project lacks quality assurance, the consequences of a time overrun are always serious and hard to resolve. It also distracts a project from meeting deadlines and this brings financial losses to the users and, more often than not, it has a negative impact on the profitability of the project for the promoters. Besides the above mentioned problems, lack of quality assurance in construction is causing litigation among architects, engineers, subcontractors and material supplies since each party is blaming each other for the problems at the building site. As a matter of fact, the positive feeling and understanding of enjoying the beauty of a house is to give a full comfort and safety of the client but due to lack of quality assurance in construction, this comfort cannot be fulfilled. In addition to this, my argument will be basing on quality assurance in design and project scrutiny. METHODOLOGY: Before this research can be accomplished its main aims and objectives, the method to use will basically base on existing informations, general observation and other internet sources which will be very useful to the topic. However, this research will be limited within the information gathered on the internet, general observation and existing information from the researchers and will provide answers to the questions in the problem formulation. RESEARCH QUESTIONS: ÃÆ'ÃÅ" How can quality be assured in design ÃÆ'ÃÅ" Problems affecting construction industry as a result of lack of quality assurance. 1.0 WHAT IS QUALITY? The term quality means different things to different people. Some takes it to be the characteristics of a product or service that bear on its ability to satisfy a need. Whilst others take it as the degree to which a product exceeds a customers requirements and expectations. On the other hand, others think it is the attainment of prescribed standards. (http://www.qualitydigest.com/html/qualitydef.html) The international Organization for standardization (ISO DIS 9000:2000), formally defines quality as the degree to which a set of inherent characteristics fulfils the requirement. In the situation of quality assurance, quality is not a statement of excellence in a comparative sense. It is just a short cut for `desired quality` that should be laid down as clearly as possible. The producer, on the other hand, attempt to attain the desired quality at an optimum cost while the customer requires confidence in the producer`s ability to deliver and firmly maintain that quality. However, quality in construction is more difficult to explain. Firstly, the product is not a mechanical unit but a piece of work with specific characteristics. An example will be building construction, the product can be a whole building or just a prefabricated component that ultimately forms part of a building. Also the need to be satisfied includes not only the client but the expectations of the community as a whole, into which the completion of the building will be integrated. The construction cost and time of delivery are also important characteristics of quality. In other words, all these things must be properly introduced in designing the building and the outcome should be expressed absolutely in drawing and specifications. Besides, in the building industries, it is a traditional practice to have different contracts for design to that of the construction with the designer taking up responsibility of supervising the construction. The quality of the finished works will be controlled by ways of inspecting and testing as construction process. For example, the quality of concrete and other materials on site is judged by samples of test and thorough inspection of the finished work is done without any exception before finial acceptance. The major aim of this à ¢Ã¢â ¬Ã
âinspectional systemà ¢Ã¢â ¬Ã of quality control is to identify the mistakes after the product has been produce. Even high strength of concrete can be defective if it is not properly compacted, cured and the potential hazard of steel corrosion will not surface until some years later. In view of this, many short comings are covered up with the existence of subsequent construction and consequently the quality of the finished works cannot be assessed by the final inspection. Unlike consumer goods, problems in building work are very difficult to replace. The client is often left with no choice than to patch up the original which is the source of recurrent troubles and huge expenditure in some years to come. Sometimes, poor workmanship is disregard to keep up with expected productivity or just labour. However, to show commitment to quality, the senior management of the companies should therefore provide enough resources on site to avoid anybody cutting corners. Furthermore, an inclusive record of in process inspection is to ensure that the intended verification is actually done. The extra efforts are managerial in nature and complementary to the functional techniques of quality control in assuring the quality of the product. 1.1 WHAT IS QUALITY ASSURANCE? Quality assurance is defined a set of procedures designed to ensure that quality standards and processes are adhered to, that the final product meets or exceeds the required technical and performance requirements. Whereas, (ISO 9001:2000) also defined Quality assurance as that part of quality management focused on providing confidence that quality requirement is fulfilled. In other words, all those planned and systematic actions necessary to provide adequate confidence that a product or service will satisfy given requirements for quality. Despite all the wealth of site experience throughout the pass years, one out of ten building contracts still leads to clients dissatisfaction and complains against contractors. Researches made by the (Building Researches Establishment) in the United Kingdom indicate that 40% of building defects occurs during the construction phase (BRE, 1982). In most cases, the defects are found to be the following: ÃÆ'ÃÅ" Inadequate supervision and verification on site. ÃÆ'ÃÅ" Misinterpretation of drawing and specification. ÃÆ'ÃÅ" Ambiguous instructions or unqualified operators. ÃÆ'ÃÅ" Use of superseded drawing and specification ÃÆ'ÃÅ" Poor coordination of subcontracted work ÃÆ'ÃÅ" Poor communication with the architects, engineer, subcontractors and material suppliers. Perhaps, due to the above mention, it is obvious that the following defects rising in construction are mostly caused by poor management and communication. In this case, it is assumed that mistakes occurring on site are usually made on site. These mistakes somehow can be traced back to the purchase of incorrect materials and failure to recover the out-dated drawings. On the other hand, the end result of site problems can be of disregard or malpractices in the head office. Obviously, quality can be achieved when such preventable mistakes are avoided in the first instance. Serious measures must be taken to minimize the risk of managerial and communication problems; this is basic concept of quality assurance. Besides, the conduct of an individual in an organization could directly or indirectly affect the quality of a finished product. Responsibility for quality can therefore stretches from the chief executive right down to the person on the job. If persistent quality is to be assured, all members in the organization, both in the head office and on site must; have proper organization structure, clear lines of responsibility and communication and also to have good motivation. Before quality assurance can be practice, an organization has to be constituted and maintain a quality management system in its day to day operation. A quality system contains, among other things, a set documented procedure for the different processes carried out by the organization. Also implementing quality system does not replace the existing quality control function, nor does it conclude in more inspection and testing. It just ensures that, a proper type and amount of verification is performed when and where it is planned to be done. In short, quality assurance is oriented towards prevention of quality short coming. It also aims at minimizing the risk of making mistakes in the first place, therefore avoiding the necessity for rework, repair or reject. From the indication of the diagram above, less time and money is used in the 1st and 2nd phase, whereas less time and money is used in the 3rd and 4th phase due to the fact that mush time and money was used in the earlier phase. 1.2 PURPOSE OF QUALITY ASSURANCE (ISO 9001:2000) Quality assurance ensures that a product has achieved it highest standard and that its production, modification or repair (in the case of a manufacture item) has been completed in an efficient and timely manner. The purpose of quality assurance is there to provide assurance to a client that the standard of workmanship within the contractorÃâà ´s premises of the highest level of quality and that all the products leaving the industry is above a certain minimum level of specification. It should also further ensure that the company personnel, sub-contractors and key suppliers are aware of customer requirements and that they are fully met. Conformance with requirements of the detailed procedures developed in accordance with the Quality Manual has to be mandatory for all staff employed in the company. It is essential to the system that encouragement is given to each employee to develop and maintain an attitude of continuing quality improvement and customer satisfaction. [11] Also, to ensure that, the standard of productions are in order between the divisions or section and they have remain constant despite changes in personnel. 1.3 HOW TO IMPLEMENT QUALITY ASSURANCE Construction industry has been struggling with it implementation of quality assurance for many years. The cost could potentially be reduced reasonably if the industry were to hold onto the concept of quality assurance with the use of great success by the means other companies. (Construction Quality Assurance White paper.) However, various case studies and initiatives have succeeded in introducing quality assurance to the construction industry on a small scale, but as a whole, it has mostly been ignored by the industries. The construction industry is unique and therefore the application of quality assurance requires to be implemented in the industry. Some of the major steps of this process are discussed below; 1. First of all, project managers in various companies have to form a team or groups who will be dedicated for quality assurance. This team will be responsible to value and report on the evaluation regarding every part of the company. The team will be working individually having authority and freedom of work, at each point of their operation. The team has to report to the senior management of the company and keep all results in files. [9] 2. Once the team is formed, the main responsibility of the team will be to define the tasks and assign them to respective persons. Some of these responsibilities are to review the products, tools, services as per the requirements, standards and guidelines, audit project processes, suggest various methods, standards or tools to be used in the project, report the outcome of the evaluation etc. [9] 3. The team then defines the plans for the quality assurance process. In this case, it depends upon the nature of company; the details of the plans in the company might change. However, it basic plan remains common for most of the companies. Mostly the list includes quality objectives, defining the tests and verificational activities, process evaluation, defining the individual responsibility of the team members, identifying training requirements, budgeting and funding for quality control jobs, scheduling all activities, documenting and tracking etc. [9] 4. Generating the test process, checklists and related activities to explain the way quality assurance will be performed is the next step. [9] 5. The team in simple sense has to perform according to the plans made to ensure the next steps of quality assurance process. These resources can be acquired to perform the procedures, when the team starts evaluating the project. Tools required for this evaluation are identified depending on the nature of the project. Any non conformance with the standards or requirement are notified and reported to the appropriate department. The problems are then corrected and again sent for testing to the quality control team. This way, testing and correcting goes on, till the project is proven to be in conformance with the standard. [9] 6. The next step is to identify the training requirement for the team members to perform the evaluation processes as specified in the quality control plan. [9] 7. The performance of the team should be monitored regularly by the project manager against the plans, schedule and budget. In case the progress of the team is not doing a good job, then corrective actions should be taken. [9] 8. The team activities and results are reviewed by the senior management of the company and their stakeholders on regular intervals. Any unsolved issue for the team procedure is taken care of by the senior management at this point of time. [9] 9. The team collects review information from various sources. Again, suggestions for improvement at any step of quality assurance process is accepted and implemented in the next session, if it satisfies the various limitations. Recommendations are accepted from any level of the company for future use. [9] 10. The team refines the total process to give it a defined structure with the teamÃâà ´s descriptions, templates and checklists. This structure can be reused as a model for future or might become an example to other companies or organizations. [9] 1.4 WHY DO WE USE QUALITY ASSURANCE IN DESIGN? In the construction industry, quality assurance is adopted in nuclear and offshore works mainly for safety and reliability reasons. The process of construction involves different types of professional and tradesman with a wide range of skills and level of education. The environments where these processes are carried out are often revealing to aggressive element, in such condition it is arguable whether the procedures can be standardized at all. On the other hand some contractors think that trying to do so merely place another layer of administration in the industry. Despite, the differences of the work handled by a construction company, the corporate procedures apply to all varying degrees. Some examples of such are tendering, procurement, document control and record keeping. Mostly, the adoption of quality assurance in the construction industry has been mainly client-led. Noting that the implementation of contract in law cannot undo any damage already done, a progressive client, when awarding a contract, tends to take into account, the contractorÃâà ´s capability to do it right at the first time down the hidden philosophy of quality assurance. Besides, there is a general movement towards making the enforcement of quality systems in a contractual requirement. Most of the government bodies that are responsible for public works and housing have begun to persist on an effective quality system as an obligatory for tendering; perhaps public utilities companies are doing the same thing. In this cases, the basis of competition for industries will move from à ¢Ã¢â ¬Ã
âpriceà ¢Ã¢â ¬Ã to the combination of à ¢Ã¢â ¬Ã
âprice and qualityà ¢Ã¢â ¬Ã , meanwhile if the contractors do not want to keep out from bidding for available work, they should then wait no longer in establishing a quality system in their companies. Such contractors will be fighting a lose battle against their competitors who have already enhanced their product through better quality assurance or quality management. More so, trying to satisfy a condition for tending or contracts may not be the best argument for practicing quality assurance, but it would have probably be the most compelling reason in the first place. However, the companies that benefit mostly from quality assurance are those who do so for the purpose of improving their own efficiency. These improvement leads to higher productivity on the on hand and client satisfaction on the other. Lets see some few constructions analyze with poor quality assurance. 1. Damage to the terrace roof surface. 2. Roof leakage through joints, bushings and so on, which lead to drenching of the thermal Insulation material and discolorations on internal surface layers. 3. Roof leakage at the eave with discolorations and flakiness on the faÃÆ'à §ade surface layer underneath. Sources: 5th semester project 2009 Moisture has caused many damages through the roof terrace covering because of different reasons. Some of which are discovered in the construction by some blemish on the faÃÆ'à §ade and inside the building. The extent to which these damages can be determined is after the construction has been exposed. Besides, the deformation of this damage depends partly on changes in the supporting substrate and partly on movement of the building structure. 2.0 ROOF 2.1 BAD WORKMANSHIP And the most common damage on roof construction is water leakage More often than not, the leakage can occur anywhere in the roof construction and also at other place then where the water from the outside normally penetrates. These leakages are caused by innumerable; another reason could be a damaged roof membrane. Above all, the roof membrane can be a reckless traffic, ice blasting and thermal movements in the roof coverings. Also there can be movement underneath the roof membrane duo to shrinkage in the thermal insulation boards. The water that comes through the openings in the roof membrane is partly absorbed by the thermal insulation boards and partly penetrates the roof covering. On terrace roofs with external thermal insulation, the thermal insulation boards make up a substrate for the roof membrane. Terrace roofs with no thermal insulation or with internal thermal insulation occur more occasionally, but when it does the concrete surface becomes the substrate for the roof Membrane. The roof membrane can consist of one or two layers. Roof membranes made of one layer are usually made of: * Thermoplastic materials (mostly PVC) * Rubber materials * Polymer modified bitumen. 2.2 BENEFITS OF QUALITY ASSURANCE Quality Assurance has become basic part of most of the construction industries. Every construction industries nowadays face tough competition and hence it is essential for them to provide goods or services of high quality at low cost to their clients. Different systems are implemented in construction firms to improve upon the quality of the companies. Besides this does not only helps to satisfy the client requirements but also helps in reducing costs and increasing profits of the firms. Most of the construction industries understand the importance and necessity of maintaining good quality to survive in today market and that are laying even greater emphasis on their QA systems. The first benefit is that, it helps in understanding the wants and expectations of the client. It thus aids the industries to focus on its processes to satisfy those needs and expectations, so as to keep it client happy and satisfied. For e.g. construction companies that offer good quality of buildings to their clients get lots of contracts from the community benefit from it. They can also over shadow their competitors and enjoy good sales and profits. Secondly, quality assurance has increased the effectiveness of the construction industries. It requires that, the construction industries gives proper training to their employees so that they can understand their jobs better as well as get trained on the new technology to work and perform better. The entire construction industry works in a predefined fashion with the aid of these procedures. It helps the employees in knowing and understanding their roles and responsibilities. They also make the employees understand the different inter linkages within the departments. Thus, the employees understand the importance of teamwork in improving the quality of products and thus improve the brand value of the company. Moreover, the quality assurance improves the flow of work within the companies. It helps to identify the problem areas within the companies very early. There are regular inspections and audits that pin point the problem areas of the companies. Not only the problems of the company, but also the low quality and other problems of the vendors are highlighted during these performance inspections. The aim of these systems is to continuously improve the entire quality of the companies, so as to attain high productivity while maintaining good quality. Last but not the least, quality assurance help all the departments to work efficiently. There are fewer lags in the manufacturing of the products and as a result the construction companies benefits from a short cycle time. For e.g. if proper quality systems are implemented in a prefabricated company, it will benefit from fast and good production to its buyers. There are many big names in for instants the Danish companies that claim to serve their customers in a very short time. Such companies benefit tremendously from increased sales and clients satisfaction. In short, quality assurance is essential for companies in order to get a strong foothold in the market. These systems help the companies to work effectively, which then reduces the operational costs of the construction companies. Also, it helps to infuse confidence in the employees though training and role clarity. All this helps the construction companies to serve their clients better every day. 3.0 HOW TO DO QUALITY ASSURANCE IN DESIGN Design in itself has four phases before a project can be completed. These phases include: PRELIMINARY BRIEF OUTLINE PROPOSAL PHASE SCHEME DESIGN PHASE DETAIL DESIGN ONE PHASE DETAIL DESIGN TWO PHASE A project needs to go through all these phases before it becomes a complete one and legally accepted. Quality has to be ensured step by step as well. 3.1 QUALITY ASSURANCE IN THE PRELIMINARY BRIEF In as much as, this project is a renovation project it still has the basis for drafting the client preliminary brief. (The Constricting ArchitectÃâà ´s Manual) Preliminary brief is the sum total of the clientÃâà ´s visions and wishes / needs for a building. In most cases the clients idea should be put on paper which should comprise as follows: the client has to make the architect aware of the reason of the building; the function, location, rooms, space etc. Because the clients mostly have different backgrounds and experience with the construction projects, the brief should be presented in forms. Besides it is somehow necessary for the architect to assist or explain to the client some important informations in the project. Minutes of the conversation between the client and the consultants should be taking into consideration. These minutes can be used as basis for drafting the preliminary brief. The preliminary brief should be drafted in such a way that not only the consultants can use it but every one concern with the project, so as it can also be used as the basis for the project. 3.2 QUALITY ASSURANCE IN THE OUTLINE PROPOSAL PHASE This is a phase where materials for construction have to be taken into consideration, analysis of where to place each room as long as design is concerned to fit regulations and demands. In redesigning such a construction, the materials to be used must critically be taken into consideration. As to how and where to place for example the bathroom and the material to use in order to get a better construction and as a matter of fact it life span. As seen in the figà ¢Ã¢â ¬Ã ¦.the materials to use in the walls around the bathroom has be water proofed in order not to soaks with water. Sound and fire also has to be taken into consideration which also make construction meet the demands in law. 3.2.1 Budget ÃÆ'ÃÅ" To have a successful preconstruction phase, it is important to have an accurate first budget. The key to an accurate first budget is communication of expectations by all team members. This will lead the dialog among the team members, asking the right questions to clearly establish the scope of the project. This includes identifying phasing plans, finishes, systems, equipment and responsibilities of the owner, consultants, proprietary items and long lead items that might impact the project cost, schedule and quality. ÃÆ'ÃÅ" Preliminary detailed cost estimating and budget development must be performed at schematic design, design development and construction document phases. At each milestone design and budget must be evaluated against the master project budget for conformance with the established program price. Corrective action, if required, should be reviewed at each stage to keep the project on target. ÃÆ'ÃÅ" Contractors perform detailed independent checks of estimates with subcontractors pricing prior to competitive bidding to the subcontractor base. This is essential to ensuring accurate numbers in the variable mountain market. ÃÆ'ÃÅ" Value engineering must be done early in the process. When utilized at this stage, it is not cost cutting, but rather a process that balances the Owners goals of meeting quality, budget and schedule objectives. ÃÆ'ÃÅ" A Team if possible must be formed to provide quality assurance, constructability and multi-disciplined peer reviews to improve document quality and ultimately achieve lower base bids and reduce change order exposure. ÃÆ'ÃÅ" Proceeding to the issuance of bid documents, the bidding requirements must be established and clearly communicated to all bidders. A compiled à ¢Ã¢â ¬ÃÅ"bid book must be made in addition to the plans and specifications that helps to clarify how they intend to build the project, as well as clarifying the role of each subcontractor. This eliminates doubling up on or missing a scope. ÃÆ'ÃÅ" Contractors uses an extensive select list of qualified subcontractors and suppliers who in a position to respond to the needs of the project. 3.2.2 Schedule ÃÆ'ÃÅ" A project schedule should be developed and validated to maximize construction efficiencies and optimize owners program requirements. ÃÆ'ÃÅ" Schedules must be validated at each step in the design. ÃÆ'ÃÅ" Subcontractors must be asked for input in the schedules early on to ensure an accurate, achievable schedule. 3.2.3 Design Intent ÃÆ'ÃÅ" Evaluation reviews are performed in the design phase. Assemblies and systems are evaluated for ease of construction so they are not later discovered to be difficult or even impossible to build. The evaluation reviews can help avoid cost increases and schedule delays during construction. The Teams experience in construction should allow productive reviews and analysis of the proposed design to identify these items. ÃÆ'ÃÅ" Submittal requirements and timing must also be identified in a submittal log so that the design intent can be properly validated. ÃÆ'ÃÅ" Contractors must compare the merits of various design ideas at the preconstruction stage, including a cost analysis, life cycle analysis, schedule impact analysis and an overall quality comparison. This will give the Owner the information needed to decide which design best meets the needs of the project. 3.2.4 Workmanship ÃÆ'ÃÅ" Quality levels must be determined and incorporated in the Project Mission Statement. ÃÆ'ÃÅ" Drawings and specifications are reviewed with subcontractors and designers to identify potential conflicts, which may affect constructability and quality. 3.3 QUALITY ASSURANCE IN THE SCHEME DESIGN PHASE These stage shows where critical problems in the construction can be solved before it actually get to the detail design phase ÃÆ'ÃÅ" There must be a focus on constantly scrutinizing for value adding ideas to best meet the owners objectives. ÃÆ'ÃÅ" Contractors work to find creative solutions to problems during construction in an effort to minimize cost, schedule or quality impacts. ÃÆ'ÃÅ" Contractors provide a review of the proposed changes, with regards to cost, schedule, design, constructability and quality implications as part of the role in the change order management process during construction. ÃÆ'ÃÅ" The contractor meets all contractual schedules. This eliminates additional costs for owners due to schedule delays.
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