Types of Green Roofs

Water Conservation for Lawn and Landscape April 03, 2014|Print

Two basic types of green roofs are commonly constructed; extensive and intensive.

I. Extensive Green Roofs

PROS

  • Uses shallow soil medium making it lighter weight
  • Harsh conditions favor drought tolerant plants such as sedums
  • Minimal maintenance
  • Relatively low cost
  • Pre-planted modules are available for ease of installation

CONS

  • May require occasional maintenance such as weeding
  • May require additional irrigation during extended dry periods
Example of a simple extensive green roof
Photo credit: International Sustainable Solutions  Flickr CC BY-NC 2.0

II. Intensive Green Roofs

PROS

  • Uses deeper soil medium
  • Can support trees
  • Can use a large variety of plant types
  • High wildlife habitat value

CONS

  • Stronger roof structure is needed to support the weight so may not be appropriate for older buildings
  • Tend to be more expensive
  • Similar landscape maintenance to ground level landscapes
  • May require additional irrigation

Trees and shrubs growing on roof top terraces of the LDS Assembly Hall and Conference Center in Salt Lake City, Utah
Photo credit: Abel Cheung Flickr CC BY-SA 2.0


Additional Resources:

An Introduction to Green Infrastructure Practices
Green Roofs as Water-Wise Landscapes

West

Low Impact Development in Northern Nevada Green Roofs

Southeast

Florida: Green Roofs / Eco-roofs
Mississippi: Green Roofs for Southern Landscapes