Explore New Green Roofing Resources for Commercial Buildings

Explore New Green Roofing Resources for Commercial Buildings

Green roofing is changing the way commercial building owners and design professionals think about the roof. A green roof can help manage stormwater, moderate rooftop temperatures, protect the underlying roof system and bring nature back into dense urban environments. Johns Manville’s new Green Roofing Solutions for Commercial Buildings page brings together information and technical resources to help design professionals navigate the design and installation of commercial green roofing systems.

What Is a Green Roof?

A green roof incorporates vegetation and engineered growing systems installed above the roof membrane. Green roofing can be a strategic investment for sustainable commercial development, helping support environmental goals or code requirements while providing a solution for stormwater retention and management.

Green roof systems generally fall into three categories:

• Extensive: Lightweight systems with a shallow substrate layer, typically 3 to 5 inches, supporting low-growing vegetation such as mosses, sedums and grasses.
• Semi-intensive: Systems with approximately 6 to 12 inches of growing media, which can support grasses, herbs and small shrubs.
• Intensive/Amenity: Systems with growing media 12 inches or deeper, capable of supporting larger shrubs, trees and full-scale gardens.

Growing media can be installed using tray systems, which use modular trays, or layered systems, which incorporate drainage and protection layers over the primary waterproofing membrane.

What Is a Blue Roof?

Low-slope blue roofing systems are intended to temporarily retain or slow the release of stormwater from the roof surface. These systems can help reduce the risk of urban flooding and ease the burden on municipal stormwater infrastructure. Blue roofs may also incorporate vegetative and solar components.

Both Green and Blue roofs’ performance depends on the building’s structure, drainage capacity and design intent, requiring specialized design and input from design, engineering and trade professionals.

Technical Resources for Green Roofing Systems

Green roofs require considerations beyond standard roof construction. The JM Green Roofing Reference Guide outlines specific technical considerations for Single Ply and SBS roofing systems, including information related to decks, insulation, cover boards, membranes, attachment, leak detection and flashing.

The new JM green roofing page also provides flashing details and three-part specs for multiple green roof configurations, along with reference resources to help your design professional support project planning and installation. JM works with Columbia Green Technologies (CGT) and GreenRise Technologies (GRT) to provide single source options for commercial green roofing projects.

More Resources for Sustainable Commercial Roofing

Green roofing is one of several strategies that can support broader building sustainability goals. JM offers additional resources covering Environmental Product Declarations (EPDs), energy-efficient roofing, cool roofs and photovoltaic systems to help project teams explore sustainable commercial roofing solutions. Explore the JM Commercial Roofing Sustainability Resources page to learn more.