The integration of Quality Assurance (QA) and Quality Control (QC) provides a construction project with a unified approach to assessing the achievement of the required definition of “quality” in the project work. Although QA and QC are closely connected, novel opportunities for improving construction projects can be achieved by differentiating between the two.
Quality assurance can be seen as the management of the systems and processes that help define the frameworks to avoid the creation of defects, whereas quality control is the management of the systems and processes that help verify the achievement of the required quality standard of the project through the actual inspection of the work (both completed and in progress), and the subsequent identification of any latent defects.
QA can be seen as the management of systems and processes that help a project avoid defects, whereas QC can be seen as the management of systems and processes that help identify defects. A construction project can have excellent quality assurance through comprehensive submittal reviews and clear installation instructions for all construction trades, yet still require quality control, as even properly prepared trades can make errors that only inspection can identify.
QA/QC programs on larger commercial projects are often formalized into a written plan specifying inspection frequency, documentation requirements, and escalation procedures for defects found, particularly on projects with rigorous owner or regulatory quality expectations, like healthcare or life-sciences facilities where defect tolerance is especially low given the consequences of a quality failure in that kind of building.
One useful diagnostic for unremitting quality problems in a project that appears to have a functional QA/QC program is to determine whether the QC program is repeatedly catching the same type of defects and whether new defects of the same type keep being introduced without QA ever addressing the root cause. A persistent QC program does not solve a problem; rather, it is a sign that the QA program requires more emphasis, and the frequency of QC inspections is increased.
Should QA/QC responsibility sit with the GC, a third party, or the design team? It varies by project and owner preference, and there’s no single universally correct model. Some owners prefer an independent third-party QA/QC consultant to avoid any perceived conflict of interest arising from the GC’s self-interest in approving its own work. Others rely on the design team’s inspection role and the GC’s internal QA/QC program. They claim that the combination provides sufficient independent oversight at a lower cost than using a third party.
