Chicagoland Roofing Council Green Roofs Update

By Bill McHugh, CRC Executive Director

What’s up with Green Roofs? The Chicagoland Roofing Council (CRC) is up, with a view from the top. Read on for where roofs are going in the future, and why proven methods from the past are needed to keep these new systems viable.

“Green roofs can be of the garden, reflective, ballast or photovoltaic variety,” said CRC President Rod Petrick. “The Chicagoland Roofing Council contractors understand these technologies, and know how to make these systems work.” They only work if the roof doesn’t leak. It’s not about the panels, the plants, the light colored coatings or ballast/pavers, it’s about what’s underneath that counts: the roof.

“Garden roofs are good for the city of Chicago and good for the environment, because they are good looking, let water runoff slowly and provide reflectivity,” said CRC’s Bruce Diederich. “They displace darker color roofs, and help reduce the temperature of the city by getting rid of ‘black roofs.'”

Garden roofs protect the city’s crown jewel, Lake Michigan. Chicago has a combined sewer and water drainage system. There are times when water runoff from pavement and roofs taxes the drainage system in Chicago, and water from the combined sewer and drainage system must be sent to Lake Michigan.

Garden roofs slow the water runoff from roofs by using the soil media overburden system to slow the water flow. By holding the water on the roof longer, the surface drains at the street level can drain groundwater, while letting the rooftop water slowly trickle into the drainage system.

At the CRCA Trade Show and Seminars Roofing Industry Breakfast recently, the City of Chicago’s Brad Roback estimated that, “About 2 million square feet of garden rooftops have been installed in Chicago over the past five years.” Although that seems like a large number, 2 million square feet is a very small percentage of the total roofing market in Chicago. “It’s just under 500,000 square feet per year, about the size of two or three ‘big box’ stores like Target, Wal-Mart or Jewel,” said CRC’s Petrick. Although there are some tray systems with large square footages on top of stores like Lowes and Target, the heavier, built-in-place systems are a small percentage of the total roofing market…for now.

The garden roof concept is a costly proposition, and the roof must be installed right the first time. A conventional, low slope roof costs between $3 and $7 per square foot for new construction, depending on insulation, roof membrane type and access for the workforce and materials to work. A garden roof is between two and five times the cost of a conventional roof.

“It’s important to remember that a garden roof is first and foremost about the roof,” said CRC’s Joe McDevitt. “If the roof doesn’t work right, the cost is all for naught, and the benefits of these systems will not be realized by the city and it’s residents.”

When it comes to working above grade, the professional roofing contractor has the knowledge, company safety culture as a result of their training, the correct worker’s compensation insurance, equipment and technology to get the garden roof done right the first time.

The Building and Fire Codes have been debated during the 2009/2010 code development cycle at the International Code Council, (ICC), and have one more public hearing before the code requirements are part of the 2012 Building and Fire Codes. The 2009/2010 code cycle committee hearings in Baltimore last October and November included wind, fire resistance and maintenance to be regulated by the building codes. Most importantly, it was decided that all code requirements be scoped and referenced in and from other chapters of the code to Chapter 15, Roofing.

At ICC’s Hearings, fire marshals and building officials demanded that the garden roofing industry address wind and fire resistance through the ICC’s Building and Fire Codes. Fire marshals are asking for plants to maintain moisture so they don’t burn–or be removed. They are also requiring that fire ratings of the garden portion of the roof meet the same fire spread criteria as the roof membrane itself, all for the 2012 code.

In Chicago, there are groups working collaboratively to bring the city a new building code. CRC has participated in these groups at both the city and national levels. We have provided input to the code development process for regulations that pertain to garden roofs.

CRC collaborated with the City of Chicago developing the 2009 Urban Heat Island Ordinance, and testified to the City Council Chairs of the Committees on Buildings and Environment, to support them, and the staff that worked with us, on a process that took CRC over eight years. “We had great discussions with the City over several years, to bring the professional roofing contractors’ perspective to the code development process in the City of Chicago, and we were successful with achieving important goals,” said Petrick.

The rooftop is an important feature for buildings in Chicago and worldwide. Changes we likely are to see in the future include some pretty creative things. For garden roofs, new ways to keep plants from drying out on roofs during extended periods without moisture.

Photovoltaics combine energy production and energy savings on the rooftop. “Harnessing the real estate on the roof for energy production seems like a good way to turn the roof into a productive asset,” said CRC’s Chris Adler. “Look for solar and wind power to become a point of discussion for the rooftop in the future.”

Roofing systems can be conventional and still be green. The mass, along with energy saving insulation of ballasted and gravel systems, brings value to the rooftop. For reflective systems, the Urban Heat Island Ordinance requires a reflectivity of .72 initial, or .50 after three years aging, and allows the use of ballast as well.

Building code requirements will affect the types of systems configurations on roofs and integrate people where they have not been before, at the rooftop. The code development means possibly more irrigation systems, more thought to egress requirements as people use rooftops as assembly and will need to exit in emergencies. Plus, more fire extinguishing requirements and fire department water access on the roof are all important.

This all affects design, and makes it even more important that the roofing professional be the prime contractor on the roof, directing the process and outsourcing technologies where others are more efficient or knowledgeable.

It seems that energy producing photovoltaics and wind power harnessing systems will become in demand, in addition to seating and gathering areas such as shallow ponds to make the area a true garden haven for building owners and occupants.

Through an intense knowledge of all things that take place on the roof, the professional roofing contractor has the answers at the right value and right price to get this important system installed correctly. Through an efficient and safe installation process, without ever losing focus on what makes this all really work–a functioning roof–and specialized knowledge about working at heights, the professional roofing contractor and workforce is best qualified to bring a roof that doesn’t leak, yet has an overburden system that completes the system with beauty and functionality.

The technology needed to keep roofs green already exists at the professional roofing contractor’s office, field and workforce. CRC understands the materials, has the trained workforce, and understands code requirements now for wind, water and fire resistance for excellent performance on the roof.

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