A green roof, also known as a vegetated roof, is a roof that has been covered with a soil (growing medium) and vegetation.

Green roofs are effective for reducing the amount of stormwater runoff leaving a site

Consists of vegetation planted in growing media on top of a drainage layer that collects stormwater runoff and reduces the total volume of runoff through evaporation and intake from the plants

Eligible Components

  • Installation (placement of layers and planting)
  • Plant material
  • Soil media
  • Drainage system
  • Additional structural support
  • Root barrier
  • Material
  • Waterproofing
  • Insulation

Cost Share and/or Tax Credit Rates

  • Applicants, including any entity or member of the same household, will be limited to $50,000.00 in cost share
  • Permit fees are not an eligible component cost for any practice and therefore cannot receive cost-share
  • For specific amounts, contact the district office


  • Roofs must be 200 square feet or larger
  • All practices detaining and/or infiltrating runoff must be sized to treat a 1-inch rainfall volume
  • Native species or mixes that are adapted to the site conditions and intended uses are required
  • Invasive or noxious species, as identified by the DCR invasive species list, and/or the USDA noxious weed list are prohibited
  • The participant is responsible for ensuring that the proposed installation and maintenance plan meets all applicable local policies and ordinances

Green Roof Layers


Structural Strength: The structural load capacity of the roof

Access: It is important all maintenance personnel are able to access the roof. Additionally, if the roof is open to the public, measures should be included to ensure public safety

Physical Impacts: The ability of the green roof vegetation to absorb moisture, undergo evapotranspiration and survive depend upon the architectural features of the building

Longevity: Consider the longevity of all parts of the system, as well as the roof and all structural supports. The waterproofing layer of a green roof is especially important

Contact the District Office to learn more!