Green Overhead: Sustainable Roofing in Chicago

By Bill McHugh
Executive Director, Chicagoland Roofing Council

Whether it’s a new project or a retrofit, sustainability often starts at the top. Nowhere are a building’s extremes more evident than the roof: this is where heat is lost in the winter and where it infiltrates in the summer; where wind and precipitation meet the building head on, challenging it structurally while also offering unique opportunities.

Those opportunities cover a wide spectrum, and it’s important to consult a professional before installing any type of environmentally conscious roof, not only to ensure that it is expertly installed, but also so that you pick the right type for your structure. Insulation can provide excellent payback, garden roofs keep excess water out of the treatment system, while photovoltaics generate electricity and reflective roofs provide lower rooftop temperatures in the summer.

For the fourth year in a row, Chicago leads the nation in square footage of installed garden roofs, with 500,000 ft2 built in the past year, according to Green Roofs for Healthy Cities. While aesthetically pleasing to the community, garden roofs also provide excellent benefits to the building owner. Since the roof system is buried under dirt, it is shielded from the damaging rays of the sun, extending the life of the roof. However, the system needs to be installed right the first time, as unburying the roof can be costly to find and fix a leak. Also, the reflectivity of the garden roof is the same as the earth—about as environmental as it can get. Most importantly, garden roofs can slow the drainage of water, relieving our sanitary and storm runoff systems. By retaining rainwater, we can keep Lake Michigan cleaner.

Another option is a reflective roof, which can tame the soaring rooftop temperatures Chicago sees in the summer. Reflective coatings, including white, grey and even gravel and ballast, have been shown to provide reflective benefits after aging, according to studies by the US Department of Energy at the Oak Ridge National Laboratory. Chicago has many reflective roofs installed throughout the area, many by Chicagoland Roofing Council (CRC) contractors using workers trained at the world’s leading roofing industry location, the Chicagoland Roofers Joint Apprenticeship Training Center. Conversely, there are reasons to have a less reflective roof; Chicago’s climate in the fall, winter and spring means a darker color may help reduce heating loads.

New technologies exist to provide energy producing devices that are either part of the roofing membrane, or separate devices used to generate electricity while absorbing the sun’s rays. Photovoltaics are the most efficient commercially available solar panel technology on the market—so efficient that on many sunny days, a building owner may be able to sell excess power back to the grid.

One of the best paybacks for a building owner is adding insulation to the roof assembly. CRC Contractors and Local 11 Roofers are uniquely qualified to provide and install roofing systems with excellent insulation values to reduce heating and cooling bills.

Be sure to have a roofing professional check building code requirements for wind and fire resistance for all these types of roof systems. As with any major purchase like roofing, ask how long the system has been in service so you are assured longevity in a large capital asset, your roof.

Whether it’s the reflective roofs at Midway Airport, the gardens atop the Chicago Cultural Center and City Hall or the many photovoltaics on projects throughout the metropolitan area, few are as experienced with installing these systems than CRC companies. For over 100 years, this union coalition has been topping buildings in Chicago and the suburbs, and they’ve led the way locally with sustainable roofing.

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