Materials / Green (Vegetated) Roof

Green (Vegetated) Roof

single-ply

A low-slope roof assembly in which a waterproofing membrane is overlaid with drainage, growing medium, and living vegetation. Classified as extensive (shallow, low-maintenance) or intensive (deep, garden-like). The roofing family is defined by the single-ply or modified-bitumen membrane beneath the planting.

Category family
single-ply
Typical lifespan
30–50 years
Typical wind resistance
ballasted assemblies resist uplift; varies by design
Typical fire rating
Class A
Weight per square
1500–5000 lbs
Cost band
$$$$
Slope suitability
low
Typical warranty
20–30 years
Pros
  • stormwater retention and runoff reduction
  • insulation and urban heat-island mitigation
  • protects the membrane from UV, extending its life
  • habitat and amenity space
Cons
  • very heavy saturated loads require structural engineering
  • higher installed and maintenance cost
  • leak detection is more complex
Colorado notes
  • hail_performance: the growing medium and vegetation shield the membrane from hail impact
  • altitude_uv: plant selection must suit Colorado's semi-arid, high-UV climate

Sources