Roofs That Are Alive

If you want a unique rooftop, have you considered plants?—Yes, planted roofs.   They are becoming an embraced contender in establishing themselves as a viable roofing material in the roofing industry—and business is blooming; I mean booming!  Green roofs have a centuries-long history; and the re-popularization of green roofs emerged in Germany in the 1960’s and it has extended world-wide.
A green roof, also known as a living roof can make up part, or all, of a roof’s outside surface.  Certain types of vegetation are conducive to this type of venture, and when combined with a specialized growing medium over a waterproof membrane, the building’s structure becomes an eco-system in its own right with diverse benefits.

Benefits of Green Roofs:

1:  Water Runoff:

Green roofs are designed to comply with local regulations; and the benefits with utilizing green roofs are quite interesting.  In areas that utilize sewer-storm water systems, heavy rains can flood the wastewater systems, causing raw sewage to gush into local waterways.  Green roofs hold back significant amounts of water, 75% or more , which reduces water run-off rates and wastewater flooding issues.  The retained moisture is slowly released into the atmosphere while pollutants remain safely in the soil. 

2:  Energy Efficiency:

A phenomenon called the Urban Heat-Island Effect involves the natural tendency for building materials to absorb solar radiation and re-emit it as heat, which can translate into an unwelcomed temperature hike of 7 degrees Fahrenheit.  A live, green roof, used on Chicago’s City Hall building, has produced dramatic findings.  The city hall roof temperatures can be upwards of 80 degrees Fahrenheit cooler than traditionally-roofed buildings nearby, which translates into reducing cooling costs by a whopping 20-30%.

3:  Enhanced Insulation:

A roof’s insulation value can, also, be dramatically improved to the point where an impressive 26% reduction in air-conditioning needs during hot months and a 26% reduction in heat loss during cold months can be expected—this, according to a study conducted by Environment Canada.

4:  Increased Roof Lifespan:

Penn State University’s Green Roof Research Center reveals interesting findings which state that greening a roof can, realistically, increase a roof’s life-span by two to three times—quite remarkable.

Living Roofs—Plants Aren’t Just For Gardening, Anymore:

The environmental benefits of planted roofs can’t be debated; and these living roof coverings are taken very seriously, not only across the world, but across the entire spectrum of eco-friendly consumers from industry facilities to governmental complexes to private homes in urban and suburban settings.
More than 200 drought-tolerant species of plants are available to choose from to beautifully adorn rooftops.  Characteristics including moisture needs, depth of soil, heat tolerance, hardiness, bloom-color and foliage features are all taken into consideration to best suit the roof’s geographic location and personal preferences.
A properly-designed green-roof system can cost $15 to $20 per square foot, minus the waterproofing material.  Though these roofs are not entirely maintenance free, maintenance is minimal and would include a once-a-year fertilization application and possible weeding, depending on the roofing contractor and level of aesthetics desired.

Creating Your Own Green Roof:

Green roofs are, typically, installed on flat roofs but can be adapted for sloped roofs.  They can be “intensive” where a wide-variety of plants can be used in about 12” of soil; or they can be “extensive” where only about 3” of soil is needed for a more limited selection of plants.  As one might expect, “extensive” green roofs are more affordable and easier to maintain.
If this type roof interests you, consult with a structural engineer or architect to determine what might work best for your particular region and application.  Go Green!

Author Bio:
K. Carlson has a blast supporting ventures like Waters Custom Roofing through her writing.  She lives in Nebraska and specializes in spoiling grandchildren.