The impact of quality on building life cycle costs

Quality of design, material used and workmanship, affects the future operation, maintenance and rehabilitation costs of infrastructure; yet, the extent to which quality affects these costs has never been explicitly quantified. A review of current and past literature revealed that previous work in the area of the effect of quality upon life cycle costs is limited. This research represents a major study in this area and significantly advances the understanding of the impact of quality upon life cycle costs. The principal goal of this research was to determine the impact of quality upon building life cycle costs.

A collaborative research partnership was created, with the Canadian Department of National Defence, to study buildings on selected military bases in Eastern Canada. In total, 215 buildings, ranging from two to fifty years in age formed the database for the research. Construction, operations, maintenance, rehabilitation and demolition costs were gathered for all of the facilities and annual equivalent total costs were calculated for each building's entire service life, and for the first 20 years of its service life. Formulae and a scoring metric were developed to quantify the degree of quality in the initial building design, construction, and operations and maintenance (O&M), based on: a review of as-built drawings; historical contract data; and a quality perception survey of users and managers. The resulting design, construction and O&M quality scores were compared with building costs to determine if relationships between the variables could be modeled using statistical methods.

One of the most comprehensive building cost databases in Canada was created as a result of this research. It was proven that the better the design quality, the lower annual equivalent maintenance and rehabilitation (M&R) costs are for the first 20 years of a building's service life. Beyond this point, other factors begin to influence M&R decisions. A strong association between construction costs, construction quality and M&R costs could not be established. It was also concluded that it is difficult to associate O&M quality with individual building component service life and M&R costs due to the many factors, other than failure, which potentially influence service life. Thus, design quality is the best measure of initial quality and can be used to quantify the impact of quality upon building life cycle costs.