A green roof is defined as a “a contained 'green space' on top of a human-made structure below, above or at grade.” In other words, a green roof is vegetation planted on top of a building's current roofing system. Every green roof is unique in its design, objectives, and performance results. Until it becomes more cost effective and/or there are more incentives and government programs, green roofs remain about two to five times as expensive to install and maintain as most other types of roofs, with its installation cost ranging from $10 - 26 per square foot. Nonetheless, green roofs remain the "coolest" roofs in energy-efficiency and in appearance. At this time, they are best suited for owner-occupied buildings, corporate headquarters, government buildings, and city showcase buildings.
Despite the additional costs, green roofs provide multiple benefits to both the building owner and the environment. Some of these benefits include:
A tray system with its own "weeping" irrigation system
- Aesthetically pleasing roofing
- Diversion of waste to landfills
- Reduction of urban heating island effects
- Less energy usage to heat and cool buildings(most energy efficient roof out there)
- Improvement of air quality
- Creation of local jobs
- Reduction of storm water and run-off
- Improvement of water quality
- Reduction of noise pollution
The future of green roofing systems is continuously evolving. The field of green roofing has already seen some major changes in the last few years including lighter tray systems, innovations in system design, improvements in irrigation systems, and improved soil and plant composition.