Statistical Methods for Quality Improvement in Construction
Expert-defined terms from the Postgraduate Certificate in Quality Management in Construction course at London School of Planning and Management. Free to read, free to share, paired with a professional course.
Acceptable Quality Level refers to the maximum number of defects or deficiencies… #
This concept is closely related to total quality management, which emphasizes continuous improvement and defect prevention. In construction projects, acceptable quality levels are usually established through contractual agreements between clients and contractors. For instance, a construction contract may specify that no more than 5% of the total defects are acceptable, and any exceedance of this limit may result in penalties or deductions from the payment.
Acceptance Sampling is a statistical method used to determine whether a batch of… #
This technique is closely related to quality control and is widely used in construction projects to ensure that materials and products conform to the required specifications. Acceptance sampling plans are designed to balance the need for quality assurance with the cost and time constraints of inspection and testing. For example, a construction company may use acceptance sampling to verify that a batch of concrete blocks meets the required strength and durability standards.
Accuracy refers to the degree of closeness between the actual value and t… #
In construction projects, accuracy is critical for ensuring that buildings and structures are constructed to the specified design and dimensions. Inaccurate measurements or estimates can lead to cost overruns, delays, and safety risks. For instance, inaccurate surveying and mapping can result in errors in the placement of foundations, walls, and roofs, which can compromise the structural integrity of the building.
Action Plan is a detailed document that outlines the steps to be taken to… #
In construction projects, action plans are essential for implementing corrective actions and preventive measures to ensure that quality standards are met. Action plans should be realistic, measurable, and achievable, and should involve stakeholders and team members in the implementation and monitoring process. For example, an action plan may be developed to address a quality issue with a supplier, outlining the steps to be taken to resolve the issue and prevent future occurrences.
Activity #
Based Costing is a method of assigning costs to activities and tasks in a construction project, rather than to departments or functions. This approach is useful for identifying cost drivers and optimizing resource allocation. In construction projects, activity-based costing can help to reduce costs and improve profitability by identifying and eliminating non-value-added activities. For instance, activity-based costing may reveal that a significant portion of costs are attributed to rework and rectification activities, which can be reduced through quality improvement initiatives.
Actual Cost is the total cost incurred by a construction project, incl… #
Actual costs are critical for monitoring and controlling project expenses, and for identifying variances and trends. In construction projects, actual costs are often expressed as a percentage of the budgeted cost, and are used to track project performance and progress. For example, a construction company may use actual costs to identify areas where costs are exceeding budgeted amounts and take corrective actions to get the project back on track.
Analysis of Variance is a statistical technique used to analyze the va… #
This technique is closely related to quality control and is widely used to compare the performance of different processes, materials, or equipment. For instance, analysis of variance may be used to compare the strength of different types of concrete, or to identify the sources of variation in the dimensional accuracy of building components.
Andon is a visual signaling system used to notify production teams … #
In construction projects, andon systems can be used to improve quality and reduce defects by providing real-time feedback and alerts to production teams. For example, an andon system may be used to notify the production team of a quality issue with a batch of materials, allowing them to take immediate action to rectify the problem.
Assignable Cause is a specific cause of variation in a process or system,… #
In construction projects, assignable causes are critical to identify and address, as they can have a significant impact on quality and productivity. For instance, an assignable cause of variation in the dimensional accuracy of building components may be attributed to inadequate training of production staff, or inadequate maintenance of equipment.
Attribute Data refers to discrete data that can be categorized into di… #
In construction projects, attribute data is often used to monitor and control quality, and to identify trends and patterns. For example, attribute data may be used to track the number of defects or non-conformities in a batch of building components, or to monitor the compliance of construction activities with regulatory requirements.
Average Outgoing Quality is the average quality of products or services <… #
In construction projects, average outgoing quality is a critical metric for measuring quality performance and customer satisfaction. For instance, a construction company may use average outgoing quality to track the percentage of defect-free buildings or structures delivered to clients, and to identify areas for quality improvement.
Benchmarking is the process of comparing an organization's performance… #
In construction projects, benchmarking can be used to improve quality and productivity by identifying and adopting best practices and processes from other organizations. For example, a construction company may benchmark its quality management system against that of a best-in-class organization, and identify areas for improvement and implementation of new practices.
Brainstorming is a group #
based technique used to generate ideas and solutions to problems, often used in construction projects to improve quality and productivity. In construction projects, brainstorming can be used to identify and address quality problems, and to develop and implement new processes and practices. For instance, a brainstorming session may be held to identify the root causes of a quality problem, and to develop a plan to address and resolve the issue.
Cause #
and-Effect Diagram is a visual tool used to identify and analyze the causes of a problem or effect, often used in construction projects to improve quality and productivity. In construction projects, cause-and-effect diagrams can be used to identify and address the root causes of quality problems, and to develop and implement new processes and practices. For example, a cause-and-effect diagram may be used to identify the causes of a quality problem with a batch of building components, and to develop a plan to address and resolve the issue.
Certification is the process of verifying that an organization or indi… #
In construction projects, certification can be used to ensure that construction activities are carried out by qualified and competent personnel, and that buildings and structures are designed and constructed to meet the required standards and codes. For instance, a construction company may obtain certification to a quality management standard, such as ISO 9001, to demonstrate its commitment to quality and customer satisfaction.
Checklist is a document or tool used to verify that a set of ta… #
In construction projects, checklists can be used to verify that construction activities are carried out in accordance with approved plans and specifications, and that quality control measures are in place. For example, a checklist may be used to verify that a batch of building components has been inspected and tested in accordance with quality control procedures, and that any defects or non-conformities have been identified and addressed.
Control Chart is a graphical tool used to monitor and control</… #
In construction projects, control charts can be used to identify and address quality problems, and to develop and implement new processes and practices. For instance, a control chart may be used to track the number of defects or non-conformities in a batch of building components, and to identify trends and patterns in the data.
Control Limit is the maximum or minimum value of a metric o… #
In construction projects, control limits can be used to identify and address quality problems, and to develop and implement new processes and practices. For example, a control limit may be established for the number of defects or non-conformities in a batch of building components, and any exceedance of this limit may trigger corrective actions or process improvements.
Corrective Action is an action taken to address and resolve … #
In construction projects, corrective actions can be used to identify and address the root causes of quality problems, and to develop and implement new processes and practices. For instance, a corrective action may be taken to address a quality problem with a batch of building components, such as rework or replacement of defective components.
Cost #
Benefit Analysis is a method used to evaluate the costs and benefits of a project or initiative, often used in construction projects to justify investments in quality improvement initiatives. In construction projects, cost-benefit analysis can be used to evaluate the costs and benefits of different quality control measures, and to identify the most cost-effective solutions. For example, a cost-benefit analysis may be used to evaluate the costs and benefits of implementing a new quality management system, and to identify the potential returns on investment and cost savings.
Cost of Quality is the total cost of quality #
related activities, including prevention, appraisal, and failure costs, often used in construction projects to evaluate the effectiveness of quality control measures. In construction projects, the cost of quality can be used to identify areas for improvement and optimize quality-related activities. For instance, the cost of quality may be used to evaluate the effectiveness of a quality control program, and to identify opportunities for cost reduction and quality improvement.
Customer Satisfaction is the degree to which a customer's expectations… #
In construction projects, customer satisfaction can be used to identify areas for improvement and optimize quality-related activities. For example, customer satisfaction surveys may be used to evaluate the quality of buildings or structures delivered to clients, and to identify areas for improvement and quality enhancement.
Data Collection is the process of gathering and recording data, <b… #
In construction projects, data collection can be used to identify and address quality problems, and to develop and implement new processes and practices. For instance, data collection may be used to track the number of defects or non-conformities in a batch of building components, and to identify trends and patterns in the data.
Defect is a non #
conformity or departure from the specified requirements or standards, often used in construction projects to identify and address quality problems. In construction projects, defects can be used to identify areas for improvement and optimize quality-related activities. For example, defects may be used to track the number of non-conformities in a batch of building components, and to identify root causes and corrective actions to address the issue.
Design for Manufacturability is a method used to design products or co… #
In construction projects, design for manufacturability can be used to reduce the number of defects and non-conformities, and to improve the overall quality and reliability of buildings and structures. For instance, design for manufacturability may be used to design building components for ease of assembly and installation, reducing the risk of errors and defects during construction.
Design of Experiments is a statistical technique used to design an… #
In construction projects, design of experiments can be used to identify the optimal combination of parameters and variables to achieve a specific outcome or result. For example, design of experiments may be used to identify the optimal mix of materials and proportions to achieve a specific strength and durability of concrete.
Deviation is a departure from the specified requirements or sta… #
In construction projects, deviations can be used to identify areas for improvement and optimize quality-related activities. For instance, deviations may be used to track the number of non-conformities in a batch of building components, and to identify root causes and corrective actions to address the issue.
Document Control is the process of controlling and managing docume… #
In construction projects, document control can be used to reduce the risk of errors and defects, and to improve the overall quality and reliability of buildings and structures. For example, document control may be used to manage and control design documents, specifications, and construction plans, ensuring that all stakeholders have access to the most up-to-date and accurate information.
Efficiency is the ratio of output to input , often us… #
In construction projects, efficiency can be used to identify areas for improvement and optimize quality-related activities. For instance, efficiency may be used to evaluate the productivity of construction activities, and to identify opportunities for cost reduction and quality improvement.
Failure Mode and Effects Analysis is a method used to identify and eva… #
In construction projects, failure mode and effects analysis can be used to identify and mitigate potential risks and hazards, and to improve the overall quality and safety of buildings and structures. For example, failure mode and effects analysis may be used to identify the potential failure modes and effects of a building component, and to develop mitigation strategies to reduce the risk of failure and defects.
Fishbone Diagram is a visual tool used to identify and analyze the… #
In construction projects, fishbone diagrams can be used to identify and address the root causes of quality problems, and to develop and implement new processes and practices. For instance, a fishbone diagram may be used to identify the causes of a quality problem with a batch of building components, and to develop a plan to address and resolve the issue.
Flowchart is a visual representation of a process or system … #
In construction projects, flowcharts can be used to identify and address quality problems, and to develop and implement new processes and practices. For example, a flowchart may be used to map the construction process, identifying key activities and decision points, and to develop a plan to improve the overall quality and efficiency of the process.
Histogram is a graphical representation of data , often used… #
In construction projects, histograms can be used to identify and address quality problems, and to develop and implement new processes and practices. For instance, a histogram may be used to track the number of defects or non-conformities in a batch of building components, and to identify trends and patterns in the data.
Improvement is the process of making something better or more e… #
In construction projects, improvement can be used to identify and address quality problems, and to develop and implement new processes and practices. For example, improvement may be used to develop and implement a new quality management system, or to optimize the construction process to reduce costs and improve quality.
Inspection is the process of examining or evaluating something, <b… #
In construction projects, inspection can be used to identify and address quality problems, and to develop and implement new processes and practices. For instance, inspection may be used to verify that a batch of building components meets the required specifications and standards, and to identify any non-conformities or defects that need to be addressed.
Internal Audit is an process of evaluating an organization's complianc… #
In construction projects, internal audits can be used to identify and address quality problems, and to develop and implement new processes and practices. For example, an internal audit may be used to evaluate the effectiveness of a quality management system, and to identify areas for improvement and quality enhancement.
ISO 9001 is an international standard for quality management systems</… #
In construction projects, ISO 9001 can be used to ensure that quality control measures are in place and effective, and to improve the overall quality and reliability of buildings and structures. For instance, a construction company may obtain certification to ISO 9001 to demonstrate its commitment to quality and customer satisfaction.
Just #
in-Time is a production system that aims to produce and deliver products just in time to meet customer demand, often used in construction projects to improve quality and productivity. In construction projects, just-in-time can be used to reduce the risk of errors and defects, and to improve the overall quality and reliability of buildings and structures. For example, just-in-time may be used to manage the delivery of building components, ensuring that they are delivered to the construction site just in time to meet the construction schedule.
Kaizen is a philosophy of continuous improvement , often use… #
In construction projects, kaizen can be used to identify and address quality problems, and to develop and implement new processes and practices. For instance, kaizen may be used to develop and implement a new quality management system, or to optimize the construction process to reduce costs and improve quality.
Lean Construction is a methodology that aims to minimize waste and… #
In construction projects, lean construction can be used to reduce the risk of errors and defects, and to improve the overall quality and reliability of buildings and structures. For example, lean construction may be used to streamline the construction process, eliminating non-value-added activities and reducing waste.
Maintainability is the ease with which a product or system can be… #
In construction projects, maintainability can be used to reduce the risk of errors and defects, and to improve the overall quality and reliability of buildings and structures. For instance, maintainability may be used to design building components for ease of maintenance and repair, reducing the risk of errors and defects during construction and operation.
Mean Time Between Failures is a metric used to evaluate the reliabilit… #
In construction projects, mean time between failures can be used to identify and address quality problems, and to develop and implement new processes and practices. For example, mean time between failures may be used to evaluate the reliability of building components, and to identify opportunities for quality improvement and reliability enhancement.
Metrology is the science of measurement , often used in cons… #
In construction projects, metrology can be used to identify and address quality problems, and to develop and implement new processes and practices. For instance, metrology may be used to verify that a batch of building components meets the required specifications and standards, and to identify any non-conformities or defects that need to be addressed.
Non #
Conformity is a departure from the specified requirements or standards, often used in construction projects to identify and address quality problems. In construction projects, non-conformity can be used to identify areas for improvement and optimize quality-related activities. For example, non-conformity may be used to track the number of defects or non-conformities in a batch of building components, and to identify root causes and corrective actions to address the issue.
Operational Excellence is a philosophy of achieving excellence in… #
In construction projects, operational excellence can be used to identify and address quality problems, and to develop and implement new processes and practices. For instance, operational excellence may be used to develop and implement a new quality management system, or to optimize the construction process to reduce costs and improve quality.
Pareto Analysis is a method used to identify and evaluate the most… #
In construction projects, Pareto analysis can be used to identify and address quality problems, and to develop and implement new processes and practices. For example, Pareto analysis may be used to identify the most common causes of defects or non-conformities in a batch of building components, and to develop a plan to address and resolve the issue.
PDCA Cycle is a methodology used to plan , do , check ,… #
In construction projects, the PDCA cycle can be used to identify and address quality problems, and to develop and implement new processes and practices.