Despite the rapid expansion of green roof installations in the United States, little empirical evidence exists regarding their long-term persistence or post-installation management. This study evaluates post-installation outcomes for 46 green roofs across ten southeastern U.S. states using a structured survey and publicly available records. Roofs were classified by status (managed, abandoned, removed, mid-refurbishment, or unknown) and management intensity. Associations with ownership change, building type, and Leadership in Energy and Environmental Design (LEED) certification status were examined using Fisher’s Exact Tests and logistic regression. Only 47.8% of roofs were actively managed at the time of data collection, while 45.7% had been abandoned or removed. Ownership change was significantly associated with roof failure (Fisher’s Exact Test, p = 0.001), with no managed roofs experiencing post-installation ownership turnover. In contrast, LEED certification status was not associated with either roof persistence or management intensity. These findings indicate that institutional continuity and sustained management play a critical role in determining long-term green roof outcomes and suggest that installation-based incentives may overestimate the number of functioning green roofs. By shifting evaluation beyond ecological performance metrics alone, this study highlights governance and institutional stability as central factors shaping roof longevity.
Wishart et al. (Fri,) studied this question.