Based on Whole Building Design Guide, Cool metal roofing is a family of sustainable, energy efficient roofing products comprised of unpainted metal, prepainted metal, and granular-coated metal. It is available in a wide variety of finishes, colors, textures, and profiles, for steep-slope and low-slope applications. Cool metal roofing products are part of an interdependent system of exterior roofing surfaces, substrates, underlayments, configurations, ventilation, and insulation.
With proper design, cool metal roofing systems save energy by reducing a building’s cooling and/or heating load. Many metal roof systems are reflective, easily vented, and lend themselves well to insulated roof systems to help reduce heat gain into a building. Many products are also formed in ways that stop heat transfer through conduction by allowing only minimal contact between the metal and the underlying structure.
What is a Cool Roof?
A cool roof, based on ABC Metal Roofing, reflects and emits the sun’s heat back to the sky instead of absorbing and conducting it to the building below. “Coolness” is measured by two properties, solar reflectance and thermal emittance. Both properties are measured from 0 to 1 and the higher the value, the “cooler” the roof.
Cool Metal Roofing Explained
ATAS International enumerated some important points about cool metal roofing:
1. Cool Pigment Paint – Coatings: Cool pigment paint reflects infrared radiation, allowing the color to appear the same while keeping the material cooler. This helps in reducing the urban heat island effect, and many of our colors qualify for LEED Heat Island Credits.
2. Solar Ready – Standing Seam Metal Roofs are the best selection for crystalline PVs because, unlike other materials, metal offers the longest service life. When installing a crystalline system that typically is warranted for 25 years of power generation, a building owner is going to want a roofing substrate that has a greater life expectancy than that of the solar panels
3. Above Sheathing Ventilation (ASV) – This cool roof installation method creates an air space between a roofing panel and the deck.
Benefits of Cool Metal Roofing
There are many benefits of owning a cool metal roof according to Cool Metal Roofing. Here are just a few to consider:
- Energy Efficiency
- Low Life-Cycle Costs and Durable
- Fire and Wind Resistant
Energy Savings with Cool Metal Roofing
More and more, homeowners are seeking out energy-saving building materials for their renovations and new homes, products that not only secure and improve structures but also provide long-term cost-cutting on energy bills while promoting environmental and economic sustainability in the greater community.
Among the array of possible upgrades, Metal Roofing said that the “cool metal roofing” easily answers this consumer demand offering a solid, attractive roofing solution available in multiple colors, textures, and profiles, for steep-slope and low-slope applications, that can save your household up to 40% of its annual energy costs, depending on your geographical region.
Thousands of homeowners are turning to cool metal roofing as an innovative way to enhance the value and beauty of their homes. Your home is probably your biggest investment so improving and maintaining it should be a top priority.
According to Classic Metal Roofing Systems, Many roofing options, though, only restore the value that was lost from having an aged roof on the home. They do little or nothing to provide lasting additional value. The benefits of metal roofing, though, provide increased value that stays with your home instead of diminishing over time. Chief among those benefits is energy efficiency.
Cool roof performance is a function of two radiative properties: Solar Reflectance and Infrared Emittance.
Solar reflectance is defined by the Cool Roof Rating Council (CRRC) as, “The ratio of the reflected flux to the incident flux”. In other words, the number reported for solar reflectance for a roof product is a decimal number less than one that represents the fraction of light reflected off the roof. For example: “high” reflectance materials, such as white painted metal roofing, have values of around 0.70 (a.k.a. 70%). That is, only 30% of the light from the sun is retained by the roof.
Infrared emittance is defined by CRRC as, “The ratio of the radiant heat flux emitted by a sample to that emitted by a black body radiator at the same temperature”. In plain terms, emittance is a decimal number less than one that represents the fraction of heat that is re-radiated from a material to its surroundings – See more at: