Cool Roof Savings Estimates for Flat Roofs in Long Beach

A flat roof takes the full force of the Southern California sun. A white, reflective membrane sends more of that heat back to the sky, which can mean less heat in the rooms below and less work for your air conditioning. As a Long Beach roofing company that installs single-ply PVC on homes and commercial buildings, we'd rather show you honest ranges than a sales pitch. Below are estimated ranges, and the assumptions behind them, so you can judge for yourself.

Estimated Cooling Savings by City and Roof Size

The cards below show estimated cooling electricity saved per year, and the estimated dollar value of that electricity, for a white PVC cool roof (we install IB Roof Systems PVC) compared with a dark roof. It assumes a low-slope roof over air-conditioned space. Each range runs from a roof with R-10 insulation (lower number) to a roof with little or no insulation, about R-4 (higher number). One roofing square is 100 square feet.

Compared With Today's Code-Minimum Cool Roof

California's Title 24 energy code already requires a cool roof on most low-slope reroofs. That means a membrane with a rated aged solar reflectance of at least 0.63, or a Solar Reflectance Index of at least 75, when a large enough share of the roof is replaced or recovered (on commercial buildings, more than half the roof or more than 2,000 square feet, whichever is less). Exceptions apply, and we confirm the rule for your project.

So on most projects the real choice is which cool roof, not cool versus dark. The white PVC we install has a CRRC-rated three-year aged solar reflectance of 0.74, above the code minimum. These cards show the estimated extra savings over a code-minimum cool roof:

The larger ranges in the first set of cards apply only when the roof being replaced really is dark, for example an older roof that predates today's code, or a project the code exempts.

The Assumptions Behind These Estimates

In plain words, these estimates assume:

• Your building: a flat or low-slope roof with air-conditioned space directly below it. Over a garage, attic, carport or storage area that isn't cooled, the savings can be close to zero.
• Insulation: from about R-10 (lower end of each range) down to R-4, or little insulation (higher end). A better-insulated roof saves less.
• Air conditioning: an older, typical-efficiency A/C system (COP 3.0). A newer, more efficient system means smaller savings.
• Heating: a gas furnace heats the building. A cool roof lets slightly more heat escape in winter, so a small winter heating cost is subtracted. We used SoCalGas residential rates of about 1.39 to 1.86 per therm (in dollars), effective October 10, 2026.
• The roofs compared: the new white PVC uses its rated three-year aged reflectance (0.74) and emittance (0.87), not brand-new values. The "dark roof" reflects 5% of sunlight. The code-minimum cool roof is aged reflectance 0.63, emittance 0.75.
• Climate: long-term average weather from ORNL stations for Long Beach and Los Angeles. Daggett (Mojave Desert) stands in for the Coachella Valley.
• Not included: demand charges, changes in A/C size, maintenance, roof dirt or ponding, shading, solar panels on the roof, and any rebates or tax effects.
• Rounding: results are rounded and shown as ranges, because no two buildings are the same.

Electricity rates used (published rates as of October 21, 2026)

How We Estimate

We use the U.S. Department of Energy / Oak Ridge National Laboratory (DOE/ORNL) Cool Roof Calculator method for low-slope roofs. The DOE/ORNL method is a public calculation method. Neither the DOE, ORNL nor any manufacturer has reviewed or endorsed these estimates.

Cool Roof Savings FAQ

How much could a cool roof save on a flat roof in Long Beach?

For a 1,000-square-foot low-slope roof over air-conditioned space in Long Beach, we estimate a white PVC cool roof could save about 520 to 1,010 kWh of cooling electricity a year compared with a dark roof. At published SCE rates as of October 21, 2026, that is est. $140–$370/yr. This is an estimate only, not a guarantee. Results vary with insulation, A/C use and efficiency, roof condition, weather, occupancy and utility rates.

Does California already require a cool roof when I replace my flat roof?

On most low-slope reroofs, yes. California's Title 24 energy code requires a roofing product with a rated aged solar reflectance of at least 0.63 (or SRI 75) when a large enough share of the roof is replaced or recovered. Exceptions apply, and we confirm the requirement for your project.

How do you estimate cool roof savings?

We use the U.S. Department of Energy / Oak Ridge National Laboratory Cool Roof Calculator method for low-slope roofs, with ORNL climate data, the membrane's rated three-year aged reflectance and emittance, an insulation range of R-4 to R-10, a typical older A/C efficiency, and published utility rates. Results are estimates based on those assumptions, not a guarantee or promise of savings, and not energy-audit, tax or financial advice.

Will a cool roof save money if the space under the roof is not air-conditioned?

Probably very little. Cool roof savings come from reduced air-conditioning use, so over an unconditioned garage, attic or storage space the estimated savings can be close to zero.

Important Notice

Get a Cool Roof Estimate for Your Building

We'll measure your roof, check the insulation and what's underneath, confirm what Title 24 requires for your project, and give you a written estimate with an estimated savings range and the assumptions behind it. BYLTup is based in Long Beach at 20960 S Brant Ave. Call (562) 414-4425 for a free estimate.

We serve flat-roof owners across Long Beach, Los Angeles County (Los Angeles, Pasadena), Orange County (Seal Beach, Huntington Beach, Costa Mesa, Newport Beach) and the Coachella Valley (Palm Springs).

See our flat roof installation and commercial roofing services. Planning solar or new gutters too? We can plan them with your roof.