Cool Roofing has been in the press from time to time over the past few years, but since the California energy crisis, the topic has gained even more interest. The nation’s largest user of electricity is the federal government, and President Bush has made energy a key issue for his administration. So, it is no wonder that energy-efficient cool roofing is more popular than ever.
Many energy- related programs and initiatives are underway at all levels of our government. They involve cool roofing and have a potential impact on the metal roofing industry. While many other organizations are working in this area, the examples from the major efforts described here illustrate the magnitude and complexity of this issue.
In the spring of 2001 predictions and headlines began preparing us for brown outs, rolling black outs, rate hikes, hotel energy surcharges and energy shortages. The downturn in the economy starting last summer along with unusually cool weather helped prevent many of these predictions from coming true, but the underlying problem of high demand in peak times remains a reality. Despite the attention drawn to California, the energy problem is nationwide.
Roofing’s influence on energy needs
Roofing has a profound affect on energy usage since the roof is normally the least durable and least energy efficient component of the building envelope. Buildings in this country cost owners more than $250 billion annually in energy. With 81 million or more buildings in our country now and 38 million more projected to be built over the next 20 years, the challenge for the construction industry is how to build them smarter and more energy efficient.
The residential component also has more of an impact on air pollution than cars. According to the EPA, the average house is responsible for emitting almost twice as much CO2 (22,000 lbs) into the atmosphere than the average car. This is from natural gas, fuel oil, propane and coal burned either in the home or at the power generation plant providing the electricity.
If you think of what happens when sunlight strikes a roof, you realize how a cool roof can influence the cooling and/or heating of a building. Heating of the roof surface occurs from the solar radiation that is absorbed rather than reflected. The remaining heat in the roof can heat the air above it through convection and can pass through into the air beneath the roof through conduction. The heat that gets into the attic or air space beneath the roof can heat poorly-insulated air ducts and pass into the living space. This can impact the cooling load placed on the building’s comfort system.
Several key industry activities involve the performance of metal roofing, especially the EPA Energy Star Labeling program, the Cool Roof Rating Council, and the Oak Ridge National Laboratory metal roofing study program.
Energy Star (www.energystar.gov)
The Energy Star program provides a labeling system for products that are classified as being energy efficient. Energy Star labels can be found on computers, household appliances, and homes.
There is also an Energy Star Roof Products Labeling program. Over 160 manufacturers are listed as Energy Star labeled roof product partners, some of which are metal roofing manufacturers. The EPA’s Roofing Products program has already developed a calculator that compares the estimated energy usage in a home to others in the same area, which gives the owner an idea of how good the home is doing in terms of energy efficiency.
In the Energy Star Roofing Products program a product must meet specific reflectivity characteristics at the start and after a three-year aging period in order to carry the Energy Star label on its shipping and promotional materials.
Those thresholds are:
Steep Slope Roofing
Initial Reflectance 0.25
3-Year Reflectance 0.15
Low Slope Roofing
Initial Reflectance 0.65
3-Year Reflectance 0.50
The Energy Star program takes into account only solar reflectance, with no specification for emittance. Also, the steep slope roofing criteria allow for roofing products that some would not consider truly "cool". For example, some asphalt shingle products can meet the steep slope threshold but are not considered cool energy efficient products.
Cool Roof Rating Council
The CRRC is an organization working to develop a labeling system for qualified roof products that display the measured reflectance and emittance data in the initial condition. For age data, the CRRC is considering the use of roof panels exposed at independent weathering sites. The California Energy Commission refers to the Council as the administrative body responsible for labeling roofing materials in energy codes and regulations. The CRRC plans to have its program fully implemented by January 1, 2003 along with a directory of certified CRRC roofing products.
Although there is some confusion about what the roofing "product" is in the case of metal roofing, the prepainted metal industry has successfully defined the product as the outermost surface, which is the paint film in most cases. This is not so complicated in other roofing materials industries where the outermost surface is part of the main product, in the case of membranes, for example.
Oak Ridge National Laboratory - Metal Reflectance Study) (www.ornl.gov/roofs+walls)
The metal roofing industry and the ORNL have just completed the second year of a three-year study of the energy efficiency of metal roofing. The intent is to develop a whole-building energy model to predict energy savings as a function of roof material, using data generated from a variety of metal roofing products on the ORNL test roof. The roofing products are unpainted and painted standing seam profiles oriented in low and steep slope. An asphalt roof is used as a control in the steep slope orientation.
A calculator for the energy model is now on the ORNL website based on data from the low slope program. This was developed with metal and non-metal roofing performance data. A similar model for steep slope roofing is not yet ready. The third year of the program will be providing the necessary information for that to happen.
The big news in Congress during 2001 was the Securing America’s Future Energy (SAFE) Act, commonly referred to as the Energy Bill. Acting on Pres. Bush’s desire to keep energy a central theme of his administration, Congress collected many bills and rules and combined them into a mammoth 530-page Energy Bill. This bill has over $33 billion in tax breaks and incentives associated with it. (www.house.gov/rules/hr4.pdf)
The Bill’s section on energy conservation refers to tax credits for new home construction and renovation that involve energy-efficient improvements. The metal industry was successful in adding language that identifies metal roofing in the definition of energy-efficient component of the building envelope. The SAFE Act was approved by the House of Representatives prior to its summer 2001 recess, but as of the writing of this article, the Senate has not acted on it.
Other specific House and Senate bills provide incentives to introduce new technology to reduce energy consumption in buildings. These apply to commercial and residential construction. Two examples are H.R. 778 introduced in February 2001 and S. 207 introduced in January 2001.
At the Department of Energy, a flurry of activity is underway with programs aimed at developing sustained material construction, new technology and improved energy efficiency of the construction industry. Some of these programs include the Green Building Program, Building Envelope Technology Roadmap 2020, Million Solar Roofs Initiative, the R30/30 program and other community energy programs.
U.S. Green Building Program (www.usgbc.org)
The Green Building Program is a national effort to promote environmentally friendly construction practices, which includes sustainable building materials. Part of the program involves a certification or policing program that is performed by several agencies. For this, the DOE seems to be adopting the Leadership in Environmental & Engineering Design (LEED) certification that uses a 1-5 star range to rate the levels of "greenness" in a building.
Building Envelope Technology Roadmap 2020 (www.eren.doe.gov)
This is a cooperative effort between the DOE and industry to conduct research necessary to make buildings net producers of energy within 20 years. Research partners are being selected and projects are being slated for these research dollars at this time. The window and lighting industries are heavily involved in this initiative, but the metal industry is not yet participating.
Million Solar Roof Initiative (www.eren.doe.gov/millionroofs)
The DOE has embarked on a mission of assisting in the installation of solar systems on one million rooftops across the nation by 2010. This is another partnership between DOE, local governments and the private sector. The solar energy systems can be either thermal panels or photovoltaic roofing systems. This presents an opportunity for metal roofing with laminated photovoltaic films. Such films are already under evaluation on metal panels at the ORNL lab.
This program is an example of how ORNL can work with the DOE and industry to create an R-30 equivalent in thermal efficiency on buildings in 30 years. This is a major challenge since the typical insulation value on commercial buildings today is R-12. Some of the more advanced concepts being tested include highly efficient skylights, green (vegetative) roofs, and "electric roofs" using photovoltaic cells.
The U.S. Housing and Urban Development Agency is spearheading the Partnership for Advancing Technology in Housing (PATH) program. This involves $1.1 million of grants for energy-saving research in the area of residential construction administered by the Building and Fire Research Laboratory of the National Institute of Standards and Technology (NIST). With these types of programs underway, there is a need to ensure that improvements are actually being made in energy usage. This has spawned a new industry of home energy rating companies such as the National Home Energy & Resources Organization (NHERO) and the Residential Energy Services Network (RESNET). These groups inspect homes and compare the construction methods against model energy codes, using codes from 1992, 1993 and 1998 as baselines. From these data, the groups calculate which estimated energy-efficiency improvements can be tied to monetary benefits such as credits, special interest loans, mortgages and rebates.
Special mortgages are now becoming available to homeowners who meet certain criteria for improvements in their energy efficiency construction. Often these are tied to Energy Star Homes and are associated with Fannie Mae, GMAC mortgage and The Mortgage Bankers Association of America.
In Florida, hot roofs create hot attics. Since the return ductwork for air conditioning is often in the attic cavity, this can affect the cooling load. In fact, ducts are one of the largest sources of added cooling load requirement on homes in this state.
Florida has a renowned research organization called the Florida Solar Energy Center (www.fsec.ucf.edu), where much research on roofing has been conducted. A recent study in cooperation with Habitat for Humanity found that white painted metal roofing outperformed other traditional materials in a controlled experiment involving actual homes. The other roofing materials included dark gray shingles, white shingles, white flat tile, white tile, and terra cotta S-shaped tile. These results are being used by the state to promote the use of these white metallic roofs for energy conservation. (www.fpl.com/news)
The California Energy Commission (CEC) has created a cool roof savings program with millions of dollars available as incentives to non-residential building owners. The intent is to create an incentive to reduce electricity use by 20% by installing reflective roofing materials and roof insulation. Eligible customers receive $0.05 to $0.25 per square foot of installed roofing depending on the existing roof and ceiling insulation levels.
The initial guidelines made metal roofing ineligible for this program, with language that stated "use only non-metallic roofing materials." The CEC described metal roofs as being reflective but hot and therefore not "cool roofs". (www.consumerenergycenter.org/coolroof)
After several trade associations met with the CEC to discuss the situation with metal roofing, the CEC agreed to remove the negative language. The associations involved in this effort were the NCCA, MCA, MRA, NamZAC and the Aluminum Association. The CEC has now offered to work with the metal roofing industry to promote reflective metal roofing in California.
Gov. Pataki signed the first-of-its-kind law that involves state income tax incentives for owners and tenants of buildings constructed using green building principles. Green roofing is included in this legislation, but the definition does not include metal roofing. The legislation for the tax incentives is in the challenge stage. The NCCA and the MCA have submitted a position paper requesting that metal roofing, due to its ecological and energy-efficient properties, be included in the definition of green roofing. (www.dec.state.ny.us)
Two programs are under way promoting energy-efficient construction. The Atlanta Cool Community is working toward eliminating the heat island effect which involves using more reflective building materials. Another program, the Earth Craft House concept (www.earthcrafthouse.com), is a green building program offered by a select group of Atlanta home builders specially trained to build cost-effective high-performance homes that are good for the environment. They promote lower utility bills, healthier indoor air, greater durability, lower maintenance and greater comfort.
A 2001 energy-saving model home program sponsored by the state utility company features a metal roof. The program’s goal is to show how to construct an innovative high-efficiency home in a northern climate that can be heated for $300 or less per year. The model home also features pre-painted galvanized steel siding. (www.mnpower.com/energyhome)
The cool community program, first established by the DOE and later taken over by the EPA, has clearly set the standard for communities to work together with local governments to encourage the use of more reflective building materials and more trees in urban areas. Cool communities exist in Tucson, Atlanta, Houston, Sacramento, Salt Lake City, Baton Rouge, Miami and Oklahoma City.
In Frisco, Texas the local government adopted the Energy Star construction program and made it law. The "Green Building Ordinance" was created for new home construction. It includes a $500/day fine if the new construction does not meet the minimum energy-efficiency ratings. The ratings are based on analysis of the plans, inspection of insulation and ducts, and blower door/duct pressurization testing.
In Chicago, the first large-scale residential use of green roofing will be installed on the parking facility of a 17-story downtown condominium. This will be a 9,000-square-foot roof covered with a thin layer of sod, perennial gardens and ornamental trees. A similar roof is on the Chicago City Hall.
A cool roof program was stared in 1999 to cope with a heat wave that swept the city that summer causing the deaths of several elderly residents. Rather than simply providing fans to low income housing, the city, the Energy Coordinating Agency of Philadelphia, the U.S. Department of Health and Human Services, and Rohm & Haas Company added reflective roofing to a large section of row homes in the city. This resulted in the savings of energy and lives.
The DOE is working with local communities on building energy programs in a variety of states stretching across the country from New Jersey to Washington state.
INDUSTRY EDUCATIONAL PROGRAMS
With the growing interest in energy and how it can be conserved by the construction industry, more conferences, workshops, expositions and seminars on this subject are appearing.
The fourth annual Energy Conference in Kansas City in 2001 was the nation’s premier gathering of energy managers who are learning about new ways to reduce energy consumption in products, equipment and buildings. The conference was sponsored by the Federal Energy Management Program, the U.S. Department of Energy, the U.S. Department of Defense, and the U.S. General Services Administration. Attendees included federal, state and military energy and property managers, municipal energy managers, school facility managers, environmental specialists, architects, engineers and contractors. The Energy 2002 Conference will be held in Palm Springs, Calif. in June (www.energy2002.ee.doe.gov). The metal roofing industry is taking steps now to present papers on reflective metal roofing and to exhibit at the Energy 2002 Conference and Expo. A first-of-its-kind conference on New Roofs for a New Century had been scheduled in New York City for October 2001 but was postponed after the September 11 terrorist attacks. It is now scheduled for April 1-2, 2002 in New York City. Organized by the Environmental Business Association of New York and the Pratt Institute Center for Community and Environmental Development, it will focus on new roofing technology that has energy and environmental impact (www.eba-nys.org). Once again, the metal roofing industry is attempting to put metal roofing on the agenda for this conference.
"Strategies in Solar-Electric Building," held in September 2001, was the first conference devoted to solar electric building technology (www.strategies-u.com). The topics presented several opportunities for metal roofing including photovoltaic laminations that are already being tested on metal SSR panels at the ORNL test facility.
In Atlanta, the Greenprints 2002 Conference will be held during February. This is the Southeast’s premier conference on sustainable design and construction. Attendees include professionals in community design, urban ecology, clean energy and high-performance building.
Editor’s note: The NAHB Research Center and the National Association of Homebuilders will host the fourth annual National Green Building Conference, March 24-26, 2002, in Seattle, Wash.
The area of cool roofing is growing in popularity and activity at all levels of our government and our country. The impact that these activities will have on metal roofing are significant, provided the metal roofing industry is positioned to benefit from them.
We need to remain alert to all opportunities where pre-painted metal roofing could be included in energy-efficiency related or environmental programs promoting energy conservation and/or sustainable building materials.
Scott Kriner is a developmental engineer in the Commercial Division of Bethlehem Steel Corporation and has more than 20 years of domestic and international experience in the hot dip coated sheet industry. He is a member of the Board of Directors for the National Coil Coating Association, chairman of the Prepainted Metal Roofing Task Force, a member of the Metal Construction Association and co-chair of its Cool Roof Task Force, a member of the Galvalume Producers of North America, and a representative to the Cool Roof Rating Council.
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