A cool roof is one of the hottest and latest trends in energy efficient and sustainable buildings. Logically, California has been a pioneer when it comes to adopting cool roofs in warm climates in the US.

Anyhow, California’s Building Energy Efficiency Standards – Title 24, Part 6 – contains specific requirements about a cool roof that can be pretty challenging to navigate.

What Is A Cool Roof?

cool roof

Cool Roofs counteract most of the harmful effects. They are using light-reflecting coatings and materials to reflect the sun’s light and emit heat rather than letting it in.

This means that communities and individuals are directly reducing energy costs, carbon emissions, and UHI (which stands for an urban heat island.)

As you might know, on a hot day, a regular roof is definitely the hottest part of the entire house and building. Wondering why so? Because it is located closest to the sun and receives a lot of direct light!

Types Of Cool Roofs

Cool roofs can fall into one of the three following categories:

  1. Roofs made exclusively from inherently cool roofing materials.
  2. Roofs made of materials coated with some of the solar reflecting coatings.
  3. Green planted roofs.

Each one comes with a unique set of benefits. Green roofs are perhaps the best in many ways, but they are also the hardest ones to construct and maintain. Coated roofs are the easiest to install, while inherently cool roofs are relatively easy to install.

Coated Roofs


A new or existing roof can be easily transformed into a reflective one by applying a solar reflective coating over its surface. Cool coatings can be applied to several types of materials, including gravel, metal, asphalt, and other single-ply materials.

Some of the cons are that some coatings have a strong odor, require removal when the roof needs recoating, lose reflectivity over time, and hold dirt.

Inherently Cool Roofs

Those types of cool roofs are achieving the highest level of reflectance and emittance among all the others roofing materials.

As a matter of fact, roofs made of thermoplastic white vinyl can reflect even more than 80% of the sun’s rays and emit more than 2/3 of the solar radiation that would be otherwise absorbed.

For example, an asphalt roof can reflect only between 5% and 25% of solar radiation, which results in enormously big heat transfer to the interior of the building, increasing demand for air conditioning.

Some of the downsides of an inherently cool roof are: relatively difficult to install, may cause glare, and tend to be varying shades of white, making grime and dirt more visible.

Green Roofs

Green roofs are actually a thermal mass layer in charge of reducing the flow of heat into a house or building.

However, their solar reflectance varies depending on the type of the plant ( generally between 0.3 – 0.5.)

Because of the something lower reflectance, they reflect less sunlight, and logically, absorb more solar heat than other types.

How do green roofs work? They absorb heat and trap it through the greenhouse effect, and then the heat is cooled by evapotranspiration.

However, they are more expensive than other options, increase in weight load, and require a bit more roof maintenance.

How Much A Cool Roof Is Going To Cost You?

We understand that installing a cool roof sounds great. But we also know that any responsible homeowner would like to know the exact price of how much a cool roof is going to cost.

Let’s make one thing crystal clear. The rough price of a roof upgrade will greatly vary, depending on the design of your home and the material used.

According to the EPA (Environmental Protection Agency), the price of a cool roof can range from $0.75 to $3.00 per sqft. Besides that, there is an installation cost that can add up to anywhere between $1500 and $6500 (NOTE that this is for a home with a more than 1.000 square ft roof.)

Is Cool Roof Worth It?

A cool roof provides plenty of perks, which makes it worth it. A cool roof not only reduces energy usage and hence saves your money, but it also helps stabilize indoor temperatures in unconditioned spaces (e.g., bonus room, garage, etc.)

Installing a cool roof is most beneficial when it comes to a warm climate like ours in Los Angeles, where the winters are not even close cold to winters in other parts of the USA.

Benefits Of A Cool Roof

When you choose a cool roof in Los Angeles, you get to take advantage of:

Significantly Reduced Energy Consumption

Since a cool roof is in charge of deflecting more heat, you can expect reduced energy use, which is really important for Los Angeles – air conditioning is not cheap – they are a huge draw on the power supply.

According to the researcher’s data, the average residential and commercial building dedicates over 10% of its energy usage to air conditioning.

Noticeable Cost Savings

Energy savings comes hand in hand with a lower electricity bill. The best part is that a cool roof is not some advanced high-tech discovery.

It relies on the simple principle that dark colors absorb more heat than light colors.

Improved Indoor Comfort

Whether your place has AC or not, a cool roof keeps your indoor air temperatures low during the summer months.

A cooler place is way more comfortable for all occupants and protects them from heat-related illnesses.

Environmental Stewardship

A cool roof is the best option for the planet.

It has many environmental advantages, including reducing energy usage, lowers greenhouse gas emissions which further reduce air pollution, and counteract the heat island effect.

Cool roofs actually reduce the temperature in your house. Depending on the entire setting, a cool roof keeps indoor temperatures lower by 2C to 6C compared to other traditional roofs.

A cool roof uses specialized materials that reflect the vast majority of the sun’s light and emit heat rather than absorbing it in your place.

All in all, as Los Angeles is the first city that requires these types of roofs for nearly all commercial and residential buildings, you can find an excellent rebate program!

If you want to learn more, please, don’t hesitate to give us a call. We do roofing in Riverside, LA, and surrounding areas.