Green roofs are growing in urban and suburban areas and it’s not just a passing fad. They’re here to stay, and for good reason. Not only do they look better than a traditional roof, they provide many environmental, functional and budgetary benefits. Take a moment and learn the many advantages green roofs offer.
Smart Storm Water Management
Green roofs moderate the flow rate storm water, reducing stormwater runoff so less water is directed into storm drains and sewer systems. The plant material used for green roofs absorbs stormwater, releasing back into the air through condensation and filtering the heavy metals in rainwater.
Typically, green roofs intercept between 15 and 90% of rooftop runoff depending on the type of growing medium and plant cover.
Better Roof Durability
Think of a green roof as a shield for your roofing material. It makes sense when you consider that the lifespan of a roof is determined by the materials used to construct and those materials' ability to withstand UV light, the contraction and expansion that naturally occurs with temperature changes and damage by wind or storms. By installing a green roof over your roofing system, you're protecting it from the elements.
Summer and Winter Insulation
During the hotter months, green roofs offer insulation against the heat. This is because green roofs release moisture as part of the natural evaporation and transpiration that occurs with the roof's plant medium. Think of it like a large "swamp cooler" pad draped across the roof, easing the heat and helping reduce AC costs. During colder months, green roofs absorb heat from the air, keeping the building warmer and helping to lower heating costs.
Urban Heat Island Mitigation
Developed cities have their own climate and it's generally warmer than the less developed surrounding areas. This is called the urban heat island effect. Green roofs help mitigate this effect with their inherent evapo-transpiration capacity. In other words, the natural processes that take place in the roof's plant material offer a cooling effect on the ambient outdoor temperatures. In combination with tree- and plant-filled landscaping, a green roof can greatly help reduce urban island effect, making today's increasingly hotter summers more bearable for all.
With every new building and development, we're eliminating our natural environment and with it go plant and animal life, as well as the soil matrix, essential to the overall health of the environment. By planting a green roof, you're enabling beneficial animals and insects to do their jobs, pollinating food crops, controlling pest populations, dispersing seeds or just making our day more wonderful with their presence. Carefully selected plant material for your green roof can help recreate lost natural environments and support biodiversity.
Effective Sound Insulation
Green roofs are good sound insulators. The growing medium on a green roof reduces lower sound frequencies, while the plants block higher frequencies. Taken in tandem, these elements help create a more peaceful environment for all who work or live in the building.
Enhanced Urban Aesthetics
Green roofs are beautiful architecturally. They hide less attractive rooftops, antennae and HVAC elements and offer a visual respite from the hard surfaces of urban life. Green roofs also instill the feeling of calm that comes with surrounding one's self with nature.
Good Long-Term Value
It's true—green roofs require a large investment in the beginning, but over time green roofs are more cost efficient than most other roofing alternatives. Green roofs can last up to 50 years and offer up to 50% in savings for heating and cooling as opposed to traditional roofing systems. Property values can also be favorably impacted for buildings with green roofs.
So, yes, green roofs are great for the environment but the benefits they offer can extend far beyond just that.