Today’s blog post is of particular interest to building owners and facility managers, as it provides an overview of the energy-saving potential of white roofs. Other posts have examined the credibility of white roof coatings and if white roof coatings are more effective than white roof paint.
What sort of energy savings could someone see with a white roof? According to the Urban Green Council, white roofs on commercial buildings could produce 89 percent net energy savings. Likewise, the United States Department of Energy estimates a white roof on a commercial building could generate annual energy savings of up to $.20 per square foot. In 2010, an Inhabitat.com article noted if 85 percent of air-conditioned buildings in the United States had white roofs, there could annual energy savings of $735 million.
However, it should be noted energy cost savings will vary based on a building’s location as well as on local energy consumption rates. In areas with a warmer climate, energy savings could be more pronounced in the hotter seasons of the year. In one California-based study, “cool roofs” were found to generate annual net savings of almost $.50 per square foot, though other buildings than just commercial buildings were factored in.
On a national scale, the ENERGY STAR® program says if commercial and industrial buildings’ energy efficiency were improved by 10 percent, there could be $20 billion in collected savings. The ENERGY STAR® program also notes that with ENERGY STAR®-qualified cool roofs, commercial buildings have cumulative cost savings of $2.7 billion and industrial facilities over $200 million. At present, U.S. commercial and industrial buildings have combined annual energy costs of $202.2 billion, with 30 percent of energy being used inefficiently or unnecessarily.
With these studies and others in hand, it is clear white roof coatings are an attractive option because of their energy cost-saving potential. That becomes even more pronounced when considered in light of how the white roof became prominent in commercial roofing.
The White Roof, a Disruptive Force in Commercial Roofing
Our professional commercial roof contractors provide:
- Roof maintenance & repair
- Inspections & leak detection
- Energy efficient roof systems
- Complete roof replacement
- Roof life-extending solutions
When the white roof coating appeared on the scene as a way to extend a roof’s life without having to do a complete roof replacement, though, the industry began to change. Because of their ability to reflect much of the sun’s heated rays off a roof surface, energy efficiency became another category for evaluating roof performance on top of protection value and service life.
Today, white roof coatings remain a hot-button topic in the commercial roofing industry. They have been accepted as a mainstream roofing product selection. For instance, since 2010 in New York City over 1 million square feet of roofing has been coated with white coating products.
These coating products have also been shown to be a great option for long-term energy savings. According to the U.S. Department of Energy’s most recent Buildings Energy Data Book, the average annual energy expenditure per square foot of commercial floor space was $2.44 in 2010. In 2014, it is expected to be $2.27.
Studies on White Roofs’ Efficacy in Generating Energy Savings
In addition to a white roof study that spanned 50 years conducted by Lawrence Berkeley National Laboratory and more, here are a couple of other notable studies that capture the energy-saving potential of a white roof.
- In Tucson, Arizona, a 24,000-square foot building was topped by a white elastomeric roof coating. Energy consumption from one summer week before the coating was noted, along with one summer week after the coating with similar weather conditions. City personnel recorded a 50 percent reduction in energy usage as a result of the new white roof and estimated it could save $4,000 in energy costs annually. With those savings, the roof would pay for itself in just over 6 years (the roof coating cost almost $25,000 to apply) and have a 16 percent rate of return.
- In Austin, Texas, a 100,000-square foot retail store had its energy use, peak air conditioning demand, and service life compared before and after a white roof membrane was installed on it. The monitoring period of the study took place over 13 months and took note of several measures. Approximately in the eighth and ninth months of the study, the retail store’s black roof was replaced with a white roof. For the retail store’s black roof, the average daily roof surface temperature was 168°F. With the white roof, it was reduced to 126°F. Total air conditioning usage was reported to have dropped down 11 percent and peak air conditioning demand by 14 percent. The building was predicted to be capable of saving $65,000 over the roof’s service life.
Some Thoughts on the White Roof and Its Energy-Saving Potential
Some people have said white roof coatings may suffer from a “winter penalty”, or a period during the winter in which they reflect useful heat from a building and make the building use more energy for keeping its interior warm.
The Cool Roof Ratings Council offers the following answers to this notion:
- Cooling cost savings tend to greatly exceed any heating cost increases
- The sun shines on a roof at a more oblique angle in the summer than it does during the winter, meaning its energy will not come down on the roof as directly
- Snow often covers a roof during the winter, cutting down on opportunities for the sun to warm up a building anyway
For calculating one’s own energy-saving potential, the Department of Energy offers a useful calculator.
Conklin White Roof Coatings
With Choice Roof Contractor Group, building owners can get the great benefits of a white roof listed above and more. Conklin white roof coatings have excellent tensile strength and durability, and have been seen to last for 25 years or longer while other white roof coatings last 10-15 years.
They also have other attractive features:
- Great track record from being used for over 40+ years
- Exclusive non-prorated warranty coverage on all labor and material costs for up to 18 years
- Up to 15 percent annual energy savings or more
- Completely seamless and waterproof roofing protection
- Instantly ends leaks and other common roof problems when applied
- Can negate winter penalty with specialized Conklin spray polyurethane foam insulation system
- Can pay for themselves in 5-7 years with energy savings
- Formulated to resist hurricane-force winds and hail storms
- Resists dirt build-up and discoloration with greater effectiveness than other roof coatings on market
Should you be interested in learning how a Conklin white roof coating system can be good for your needs, give us a call at 800-670-5583.