Preventive Maintenance vs. Reliability Centered Maintenance: Why It Matters

Reliability Centered Maintenance vs. Preventive Maintenance

Reliability-centered maintenance (RCM) and preventive maintenance (PM) are two different maintenance strategies that can be used for operating commercial buildings. The key differences between RCM and PM begin with focusing on critical equipment. RCM identifies only the necessary equipment most important for the facility’s operation, while PM typically applies to all equipment regardless of its criticality.

Set Up

When setting up your RCM program, you will apply a rigorous analysis process to identify the maintenance tasks needed to maintain critical equipment reliably and efficiently. PM typically relies on the manufacturer’s recommendations or industry best practices to determine maintenance tasks. While both are part of a scheduled maintenance routine, RCM attempts to get the most out of your labor costs while ensuring there is no critical system downtime.


RCM is a risk-based approach to maintenance, focusing on the potential consequences of equipment failure and the likelihood of failure. The RCM framework emphasizes condition-based maintenance, which involves monitoring the condition of equipment to determine when maintenance is needed. At the same time, PM relies on scheduled maintenance intervals without considering prior analysis before engaging in the activities. In contrast, PM is generally based on a fixed schedule of maintenance activities.


The RCM strategy centers on the cost-effectiveness of maintenance tasks by balancing the upfront cost against the cost of failure. The PM strategy may only sometimes consider the cost-effectiveness of maintenance tasks just because the task will need to be done using a regimented schedule to ensure you are always staying ahead of any downtime issues.

In summary, RCM and PM are two different maintenance strategies that can be used for operating commercial buildings. RCM is a more focused, analysis-based, and risk-based approach emphasizing condition-based maintenance and cost-effectiveness. At the same time, PM is a more general approach based on fixed schedules and industry best practices that avoids risk but may come at a higher premium.


  • Charles Dilley

    Vice President of Strategic Growth

    Charles helped lay the foundation for The Building People's growth from its outset through the development of the brand, marketing, growth, and business development strategy. He provides strategic management, business capture, branding and marketing, key performance measures, benchmark strategies, and strategic consulting in support of client portfolios in excess of 500 million square feet. He is an experienced project manager and business measures consultant with over a decade of experience specializing in statistical analysis, asset management, enterprise application integration, and key performance measures for private and public sector clients such as Kaiser Permanente, CenturyLink, Royal Institute of Chartered Surveyors (RICS), U.S. Government Accountability Office (GAO), and the U.S. General Services Administration (GSA). Charles holds a Masters Degree in Public Policy from George Mason University.