The objective of this study is to propose an approach that assists facility managers in obtaining the needed information to establish a proactive roof maintenance plan. Two main methodologies are used in this research. The first approach, Historical Maintenance Data Analysis (HMDA), investigates and pinpoints the root cause of roof leaks by thoroughly collecting and analyzing roof maintenance records. HMDA hypothesizes that a mathematical model can be developed to reveal relationships between potential roof leak causes and leak incidences. The second approach, Roof Service Life Prediction (RSLP), investigates the applicability of the Factor Method in roof maintenance. The use of RSLP for leak predictions is based on the assumption that the first-time leak has a linear relationship with the estimated service life (ESL) of the roof. This research demonstrates that roof maintenance records can be used to predict and identify major factors that are likely causes of roof leaks in a mathematical causal model. Roof leaks are not totally random events and can be predicted. In this study, three parameters (Age, Workmanship, and Roof Repair) have a significant impact on the roof leaks probability within the first three years of a roof life. A unit change of workmanship and roofs age increases the odds of a roof leak. On the other hand, changes in roof repair decrease the odds of a roof leak. The Factor Method performed in the RSLP confirms the existence of a relationship between the ESL and the first-time leak. The correlations discovered are positive and significant to highly significant. The extents of correlation are found to be low to medium. The finding also illustrates a relatively simple and useful factor method technique that can be applied to the roof maintenance decision-making process. The estimated service life of a roof provides a reasonable estimation of a maintenance-free period. When ESL information is used in conjunction with knowledge obtained from HMDA, the new synthesis of knowledge will expand the facility maintenance professionals ability to develop and schedule a proactive roof maintenance plan.