Staying cool in the shade of a sustainable roof

By Lori Jerome, marketing manager, PABCO Roofing. 

Save money, improve comfort and build a better world with the right roof. 

There are many questions that arise when it’s time to install or replace a roof. Some considerations include what color is wanted? How will it look in the context of both the home and the neighborhood? Are there any regulations, like homeowner’s association bylaws, that need to be considered? These are all important aesthetic decisions; especially given the sizable investment of a roof.  

However, looks are not the only decisions that need to be made, material is also a huge consideration. Some materials are designed to handle certain weather conditions, such as hail. One condition that is often forgotten when it comes time to get a roof is extreme heat. But this article from PABCO Roofing highlights how cool roof technology has developed to create a smart and sustainable roof option. 

What is a cool roof? 

A cool roof is designed to reflect more sunlight and absorb less heat compared to a conventional roof. This is achieved through two key properties: high solar reflectance and high thermal emittance. High solar reflectance ensures that a significant portion of the sun’s energy is reflected away from the building, while high thermal emittance allows the roof to shed any absorbed heat efficiently. Together, these properties help reduce roof temperatures, lower the heat transferred inside the building and decrease the surrounding ambient air temperature. 

How cool roof technology works 

• Solar reflectance: This is the measure of how much sunlight a roof reflects. A high solar reflectance means the roof reflects a larger percentage of the sunlight, thereby absorbing less heat. This is crucial in reducing the overall heat load on the building. 
• Thermal emittance: This is the measure of how effectively a roof material can release absorbed heat. High thermal emittance allows the roof to cool down quickly, reducing the heat that is transferred to the building’s interior. 

These properties are combined into a single metric called the Solar Reflectance Index (SRI). The SRI value, ranging from 0 to 100, provides a comprehensive measure of the roof’s ability to stay cool in the sun. The Cool Roof Rating Council (CRRC) measures each property after the product is initially developed and again after three years of outdoor exposure. 

Benefits of cool roofs 

1. Energy efficiency: Cool roofs reduce the need for air conditioning by keeping the building cooler, leading to significant energy savings. In non-air-conditioned residential buildings, cool roofs can lower indoor temperatures by 2.2 to 5.9°F, making living spaces more comfortable. 
2. Reduced air pollution and greenhouse gas emissions: Lower energy use translates to reduced air pollution. On a larger scale, cool roofs can help reduce the formation of ground-level ozone and decrease cooling energy across cities. 
3. Improved human health and comfort: Cool roofs can alleviate health issues related to heat, such as heat exhaustion and respiratory difficulties. Studies have shown that cool roofs can significantly reduce heat-related mortality, particularly in urban areas. 

Understanding the heat island effect 

The heat island effect refers to the phenomenon where urban areas experience significantly higher temperatures than their rural surroundings. This is primarily due to human activities and the prevalence of dark, heat-absorbing surfaces like asphalt roofs and pavements. These surfaces absorb and retain heat, increasing local temperatures and exacerbating the demand for cooling energy in buildings. 

Low-income communities often bear the brunt of the heat island effect, as they are typically located in densely populated areas and concrete jungles. These communities also face higher energy costs and health risks due to increased temperatures. By adopting cool roof technology, we can help mitigate these effects, providing equitable benefits to residents by reducing ambient temperatures and improving air quality. 

According to the Cool Roof Rating Council (CRRC), increasing the reflectivity of urban surfaces can have a substantial cooling effect on the atmosphere. If widely adopted, cool roofs could offset the warming effect of 44-57 billion metric tons of emitted carbon dioxide, equivalent to more than half of the annual global CO2 emissions in 2022. This highlights the significant role cool roofs can play in combating human impact on the environment and enhancing community health. 

PABCO’s Premier Radiance® shingles 

PABCO offers products that not only improve energy efficiency through cool roof technology but also enhance the aesthetic appeal of homes. The Premier Radiance line of solar reflective shingles is designed to reflect heat-producing ultraviolet rays from the sun back into the atmosphere, reducing heat transfer into your home and keeping it cooler. 

One standout feature of PABCO's cool roof products is their unique color offering. While true black is impossible to achieve in a cool roof due to its inherent nature of absorbing all light, PABCO has developed the darkest cool roof color available on the market for asphalt shingles. This allows you to enjoy the look and feel of traditional black shingles while still benefiting from the energy-efficient properties of a cool roof. With PABCO, you truly get the best of both worlds — shingles that help improve the environment and maintain the desired aesthetic of your home. 

Available in four rich colors, Premier Radiance® shingles ensure that homeowners do not have to compromise on style for the sake of functionality. They meet the UL790 Class A Fire Resistance Standard and certain colors are equipped with Algae Defender® for added durability. Additionally, Premier Radiance® shingles come with a Limited Lifetime Warranty, providing homeowners with peace of mind and long-term protection. 

Original article source: PABCO