You’ve undoubtedly heard the buzz about green roofs on commercial properties, and perhaps seen the impressive photos of green-roofed buildings from Chicago’s City Hall to the United States Department of Transportation Headquarters. The idea is gaining attention, but it’s not exactly brand-new – there are green roofs on U.S. government buildings in Washington, D.C. that have been in existence since the 1930s.
But would a green roof work for your commercial property? Here are a few things you need to know:
What is a Green Roof?
A green, or living roof, is essentially an installed rooftop garden that consists of a waterproof membrane, various layers of draining and insulation, and soil and plants. Though the appearance, style, and composition can vary widely, there are both extensive and intensive varieties.
Extensive green roofs are generally less accessible but also lower-maintenance, featuring shallower soil and plants like succulents and other drought-resistant varieties (or sometimes grasses or pre-vegetated mats) that require little more than rainwater in the way of watering. Intensive green roofs are more accessible and utilize more soil. The distinctions between these two affect everything from cost and labor time to structural requirements.
What are the benefits of a Green Roof for my Commercial Property?
The benefits are numerous, and both tangible and more abstract/subjective. Green roofs reduce greenhouse gases, energy and insulation needs, stormwater pollution and runoff, and flooding potential. They can increase (sometimes drastically) the lifespan of your roof, beauty and curb appeal of the property, and the availability of habitats for wildlife from birds to butterflies. In urban areas where many commercial properties exist, green roofs can also help to minimize “urban heat islands,” pockets of urban areas that collect more solar radiation and heat than those surrounding them – due in part to reduced vegetation.
In some cases, when combined with other requirements (such as water-efficient landscaping and reduced site disturbance), green roofs can also help your commercial property qualify for LEED credits.
What are the requirements for a Green Roof install?
There are structural requirements for any green roof, thus it’s imperative to consult with a structural engineer. Flat roofs, or those angled up to about 30 degrees, are usually good candidates. The structure also has to be able to support and hold the weight of a green roof, which can be substantial (about 20 lb./sq. ft.). The roof should also be in a generally sunny area. Many cities and towns have permit and other requirements for green roofs.
There are so many possibilities for commercial property green roofs! Dive deeper into the requirements and benefits with the city of Chicago’s free rooftop gardening guide, and the United States General Services Administration’s free guide exploring the “Benefits and Challenges of Green Roofs on Public and Commercial Buildings.”
Here at Bayscape we are always ready and willing to discuss your landscape installation plans! Give us a call if you think a Green Roof for your Commercial Property is a right fit for your business and employees.