Restoring a Living Roof
A green roof’s health depends on understanding how it changes over time. At 500 Kendall Street, declining vegetation prompted a comprehensive remediation plan to restore plant coverage and support long-term performance.

Approximately 1,400 square feet of the existing roof had become bare, while vegetation across the remaining area had declined by an estimated 30–40%. Recover replenished the roof with a substantial layer of engineered growing media and added sedum plugs extensively across the existing green roof. This approach helped address bare areas while allowing established vegetation to continue growing up through the new media, contributing to faster, more complete coverage.

The planting strategy also created an opportunity to increase biodiversity. Although sedum remained the primary vegetation, Recover incorporated a biodiverse pollinator mix with low-growing meadow flowers to introduce additional flowering species and provide more variety within the plant community.

Irrigation was another important part of the remediation. While sedum is well suited to green roof conditions, extended periods of summer heat can put plants under stress. The addition of sprinklers provided supplemental water when needed to help vegetation establish and sustain coverage through hotter months. Watering is kept to a minimum, with irrigation serving as an important tool for supporting plant health when conditions require it.

Finally, pavers were installed along an established pedestrian desire path to create a more defined route for workers crossing the roof. By directing foot traffic onto a durable surface, the path helped reduce trampling of the surrounding vegetation and supported more consistent plant coverage.

Together, these measures addressed several factors affecting the roof’s condition: growing media, vegetation density, plant diversity, water availability, and foot traffic. The project demonstrates how thoughtful remediation can help restore a struggling green roof while improving the conditions needed for healthy, resilient plant communities over time.