Marshall logo                                  Marshall Roofing and Sheet Metal Co., Inc.

More on Green Roofing

Marriott Boston

Renaissance Marriott Boston Waterfront Hotel
Boston, Massachusetts

The Components of a Green Roof
Factors Affecting the Hardiness of a Green Roof

The Components of a Green Roof

  1. Roofing Membrane
    Can be fluid (like hot rubberized asphalt, BUR) or single ply; EPDM, PVC, TPO or modified bitumen.
  1. Insulation
    Typically extruded polystyrene. NOTE: insulation goes beneath a fluid membrane application and above a single ply membrane.
  1. Drainage System
    A light-weight board with long-term stability and a filter fabric that allows water to pass through it will preventing fine soil to pass through it.
  1. Moisture Retention Mat
    This prevents storm water runoff by evening the flow of water of the roofing system.
  1. Root Barrier
    This protects the roofing system from vegetative root penetration.
  1. Soil or Engineered Planting Media with these characteristics.
    Resists decomposition
    Excellent aeration
    Water holding capacity
    Bulk density
    Plant support
    Nutrient supply
    Doesn’t clog filtration system
  1. Vegetation
    Depending on the intensive or extensive nature of the green roof.


Sedum is a plant genus representing about 400-600 species of leaf succulents, found throughout the northern hemisphere, varying from annual groundcovers to shrubs. The plants have water-storing leaves. Many sedums are extensively cultivated as garden plants, due to their interesting and attractive appearance and hardiness. The various species differ in their requirements; some are cold-hardy but do not tolerate heat, some require heat but do not tolerate cold. They are preferred to grass for green roofs.

  • 500 different varieties
  • Very resilient
  • Drought tolerant
  • Sedum species for various areas of the country
  • Grown in separate blocks, suppliers don’t mix cells.
  • Shipped in flats (i.e., 24 – 3” plugs to a flat or 72 – 1” plugs to a flat-- Some roofs are planted from plugs propagated off site.) Green Grid Trays, the latest development, can be designed to go directly to the roof membrane
  • Trimming can be used to “seed” the media

Factors Affecting the Hardiness of a Green Roof

  • Heat radiating from building warms the root
  • Soil depth
  • Roof orientation
  • Moisture level in soil
  • Wind
  • Reflected light/heat
  • How well established the roof is


Marshall only installs green roof systems that are fully warranteed.

Back to Green Roofing arrow


© 2007, Marshall Roofing and Sheet Metal Co., Inc. All Rights Reserved.
131 1/2 Lynnfield St., P.O. Box 3279, Peabody, MA 01960   Phone: (978) 548-6000   Fax: (978) 5148-4993  E-mail:
Services  Representative Projects  Corporate Profile  Preventive Maintenance  Client List  Safety  Affiliations  Contact Us  Home