How is a roof made "cool" by a reflective roof coating?
You can covert just about any roof in Chicago into a "cool" roof through having a reflective roof coating applied to it. You can achieve this at any time over the course of the existing roof's life. The coatings may be applied to existing and new dark-colored roofs. ENERGY STAR defines a reflective roof as one with properties of at least 50% emissivity and 65% reflectivity after 3 years of aging. Solar energy is reflected back into space to keep the surface of the roof cooler. During the heat of summer, a "black" roof gets very hot, and the solar energy gets absorbed by the building. When a reflective coating is installed it reduces heat transfer to the structure and the surface temperature of the roof. It defends against water penetration as well.
What benefits does a reflective roof coating provide?
Roof Consultants and Architects can specific a sustainable, green and simple solution that will save facility managers and building owners money and make installation for contractors easy. It can also contribute to, satisfy or meet LEED, Title 24 as well as other green rating system requirements.
Since the reflective roof coating protects and cools the surface of the roof, it:
- Reduces the temperature by 6-9 degrees inside the building it is covering
- Reduces the temperature of the roof surface by as much as 50%
- Increases the insulation's effective "R" value
- Increases the roof mounted HVAC units' efficiency
- Saves on the building's air conditioning cost
- Reduces overall energy costs for the building owner through reducing the level of "peak electrical demand"
- Creates an environment that is more comfortable in where where no air conditioning is available
- Slows down the premature aging process of a roof that is the result of UV degradation and high surface temperatures
- Results in overall reduced roof life-cycle expenses
- Reduces risk of heat-related deaths and respiratory health risks, particularly in "Heat Island" areas
- Provides clients with a cost-effective method to meet their roofing needs.
It is an environmentally friendly ("green") solution since it:
- Reduces landfill materials - 10% of all landfill waste at least is comprised of roofing materials
- Both the utility supplier and building owner save energy
- Reduces CO2 emissions which results in the building having a reduced carbon footprint
- Minimizes the building's overall environmental burden
Is it a good investment to apply a reflective roof coating?
Yes, it is an excellent investment to apply a reflective roof coating. If in certain situations installation costs are slightly higher for a reflective roof coating (which may vary), the long-term benefits that are provided will easily still offer a very good return on investment, through providing:
- Extended roof life, with the roof substrate being protected from destructive UV by better durability-coatings.
- Reduced maintenance cost over the roof's life, and coating also are a water-resistant barrier, which is an added bonus
- Improved budget management given that the roof's life extension is predictable (opportunity for re-coating the roof instead of replacing it)
- Installation risks are reduced
- Minimal disruption for occupants, operations during the application process, construction process, and money is saved in other areas besides the application and in roofing materials
- A more comfortable and desirable work environment within the building
- Opportunities for rebates, tax savings and energy credits
- Coatings are considered to be a "restoration" instead of a new roofing system installation. Therefore, usually they can be expensed within the same fiscal year that they are applied rather the amortizing the cost over the roof's life (the way that a new membrane installation is done). For some building owners that can be a big tax benefit. Check with either your CFO or CPA on how to apply this information properly to your roof.
Will I need to have the reflective roof coating installed by a special contractor?
The reflective roof coating should be applied by an experienced roofing contractor. Although the coating might look like a regular architectural coating, long-term performance and successful application does require proper preparation, as well as repair of damaged areas or leaks, and ultimately the proper selection of the right coating system and primer.