ENERGY STAR has historically used specific energy-performance criteria for roofing products, particularly for solar reflectance and the ability of a roof surface to maintain that reflectance over time. However, an important point for commercial property owners is that the ENERGY STAR Roof Products specification was sunset on June 1, 2022. Therefore, property owners should not assume that a newly purchased roofing product can currently receive an ENERGY STAR label under the former roof-product program.
What Were the ENERGY STAR Roofing Criteria?
Under the most recent roof-product specification, Version 2.3, ENERGY STAR evaluated roofing products based primarily on solar reflectance and reliability.
For low-slope roof products, the specification required an initial solar reflectance of at least 0.65 and maintenance of solar reflectance of at least 0.50 three years after installation under normal conditions.
For steep-slope roof products, the requirements were lower because of differences in roof applications and product types. The specification required an initial solar reflectance of at least 0.25 and maintenance of at least 0.15 three years after installation under normal conditions.
The specification also included reliability requirements related to manufacturer warranties. ENERGY STAR-qualified products were required to have warranties for material and manufacturing defects that were comparable to the manufacturer’s warranties for similar non-ENERGY STAR products.
Why Is Solar Reflectance Important?
Solar reflectance measures how much incoming solar energy a roof surface reflects. A roof with higher solar reflectance generally absorbs less solar energy and can remain cooler under sunlight.
ENERGY STAR’s cool-roof guidance explains that a cool roof can reduce heat transferred into a building by reflecting sunlight and by emitting absorbed heat as infrared radiation. An effective cool roof generally combines high solar reflectance with high thermal emittance.
For commercial buildings in hot climates such as Florida, these characteristics can be important when evaluating reflective roof coatings, single-ply membranes, metal roofing, and other roof systems.
Did ENERGY STAR Require Thermal Emittance?
The former ENERGY STAR roof-product criteria focused primarily on solar reflectance and its maintenance, rather than establishing a simple thermal-emittance threshold comparable to the solar-reflectance requirements.
That does not mean thermal emittance is unimportant. It remains an important characteristic when evaluating cool-roof performance. A roof surface that reflects sunlight and efficiently releases absorbed heat can have favorable thermal characteristics.
What Roofing Products Were Covered?
The historical ENERGY STAR specification addressed both low-slope and steep-slope roofing products. Examples included single-ply membranes, built-up roofing, modified bitumen, spray polyurethane foam, roof coatings, metal panels, shingles, tile, slate, and other qualifying roof products.
For commercial properties, the low-slope category was particularly relevant because it included many roofing systems commonly used on commercial buildings.
What Should Property Owners Look for Today?
Because the ENERGY STAR Roof Products program has been discontinued, owners should avoid specifying a roof solely because a contractor describes it as “ENERGY STAR roofing.”
Instead, evaluate current and independently documented performance characteristics, including:
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Solar reflectance
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Aged or maintained solar reflectance
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Thermal emittance
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Applicable CRRC ratings
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Roof-system compatibility
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Insulation and assembly design
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Manufacturer requirements
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Warranty provisions
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Local building-code requirements
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Expected service life and maintenance needs
The Cool Roof Rating Council (CRRC) can provide standardized ratings that help compare solar reflectance and thermal emittance characteristics of roofing products.
Does an ENERGY STAR Rating Mean the Roof Is Better?
Not necessarily. ENERGY STAR criteria addressed specific energy-performance characteristics; they did not guarantee that a roofing system was appropriate for every building or climate.
A commercial roof still needs to provide appropriate waterproofing, wind resistance, drainage, durability, and compatibility with the existing structure. A highly reflective product may be unsuitable if the existing roof assembly is too deteriorated for restoration, for example.
Bottom Line
The former ENERGY STAR Roof Products program established criteria primarily around initial solar reflectance, maintenance of solar reflectance, and product reliability. For low-slope products, the Version 2.3 specification required at least 0.65 initial solar reflectance and 0.50 after three years; steep-slope products had lower thresholds.
However, the ENERGY STAR Roof Products specification was sunset in 2022, so today’s commercial roofing decisions should not rely on ENERGY STAR roof-product certification as a current purchasing standard.
Shieldline Roofing can help commercial property owners evaluate reflective roof coatings, restoration systems, and replacement roofing options using current product data, roof-condition information, applicable code requirements, and the building’s long-term performance objectives.
Related Questions
- What is thermal emittance and why does it matter as much as reflectance?
- How is “cool roof” performance measured and verified?
- How do you calculate energy savings from a reflective roof in Florida?
- What is a whole-building energy model and how is the roof input?
- Is white EPDM a viable cool roof option in Florida?
Commercial Roof Coatings & Restoration
