Type I


CSI Specification: Type I (DOCX)    ----------------------------
CSI Specification: Type I (PDF)

This simplest of all green roof assemblies, is also one of the most effective. The Type I assembly includes only two components: 1) a homogenous media layer, and 2) a cushioning layer to protect the waterproofing/membrane system. The media layer performs multiple roles of absorbing moisture, supporting plant growth, and providing efficient drainage. Consequently, media selected for these assemblies is generally coarser, with a higher permeability and porosity than media used in other green roofs assemblies. Careful attention to supplying media with these proper physical properties is essential. The attraction of single media assemblies is that they offer a low cost and lightweight method of establishing a foliage cover on a green roof, making them ideal for retrofit applications. Inch for inch, single media assemblies are more effective in reducing energy costs and controlling storm water runoff than thicker and more complex assemblies. Plant selection is more critical and restricted with single media assemblies than with other types of green roofs. Irrigation is not recommended for these systems in temperate climates; however, base capillary irrigation is occasionally used. Typical assembly thicknesses range from 2.5 to 3-inches (6 to 8 cm), and Type I assemblies up to 5-inches thick are ideal for pitched roofs.

Typical Type I profile:

  • wind erosion stabilization system
  • growth/drainage media
  • slope stabilization system (for roofs pitches exceeding 2:12)
  • protection layer (mat)
  • root barrier membrane (when required)
  • waterproofing system

Data Sheet

Type I Data Sheet

Case Studies

PECO Main Office Building, Philadelphia, PA
Wal-Mart Store No. 5402, Chicago, IL