Key Takeaways
- • The 2025 Title 24 Part 6 update took effect January 1, 2026 — low-slope roofs now need aged reflectance 0.63 and SRI ~75.
- • More project types trigger compliance — any recover affecting over 50% of roof area now qualifies as a full “alteration.”
- • CZ 10–14 (Central Valley and Inland Empire) are hit hardest with the tightest prescriptive steep-slope thresholds.
- • Cool-rated product premium runs ~$0.20–$0.50 per sqft above non-cool equivalents.
- • The performance trade-off path allows extra attic insulation (R-5 to R-10) to compensate for lower surface SRI.
In This Guide
What Changed in the 2025 Update
California's Title 24 energy code updates on a three-year cycle. The 2025 Building Energy Efficiency Standards (Part 6) took effect on January 1, 2026, and materially tightened cool-roof requirements. If your prior reference point is the 2022 cycle, four things changed:
1. Tighter Low-Slope Thresholds
Minimum aged solar reflectance raised to 0.63, thermal emittance held at 0.75, corresponding to minimum SRI ~75. Older 2022 values were lower; some previously-compliant cool membranes now require upgrade.
2. Expanded Project Triggers
Tear-off plus deck-repair projects now more reliably classify as "alterations" that require prescriptive compliance. Recover projects affecting over 50% of roof area trigger full compliance.
3. Hot-Zone Steep-Slope Tightening
Prescriptive requirements in CZ 10-14 (Central Valley, Inland Empire, Desert) now demand cool-rated products on steep-slope roofs at meaningfully tighter levels than the 2022 cycle.
4. Stricter CF Form Enforcement
Permit officials are more rigorously checking CF1R (design) and CF2R (install) forms at inspection, with fewer retroactive-approval accommodations. Document compliance on the front end, not after installation.
For a broader overview of Title 24 that is not specific to the 2025 update, see ourCalifornia Title 24 Cool Roof Guide.
Does the 2026 Update Apply to My Project?
Three factors determine whether the 2025 Title 24 cool roof requirements apply to your specific roofing project:
Factor 1: Permit Date
Projects with permits pulled on or after January 1, 2026 are subject to the 2025 update. Projects permitted under the 2022 cycle (before Jan 1, 2026) remain under the prior standards for the duration of that permit. If your roof is old enough that you are thinking about replacement, you will be permitting under the new 2025 rules.
Factor 2: Scope of Work
Full tear-off and replacement triggers full compliance. Recover (install over existing) triggers compliance when affecting over 50% of roof area. Localized repair under approximately 300 square feet usually does not trigger compliance. New construction always complies with whatever cycle is active at permit date.
Factor 3: Climate Zone
California has 16 climate zones. CZ 1 (far north coast) and CZ 16 (high Sierra) are heating-dominant and have minimal cool-roof requirements. CZ 2-15 have progressively stricter cool-roof requirements, with CZ 10-14 (Central Valley / Inland Empire / Desert) carrying the tightest prescriptive thresholds. Check your zone at energy.ca.gov or use the interactive tool below.
SRI, Aged Reflectance & Thermal Emittance Explained
The three metrics that govern Title 24 cool-roof compliance are not interchangeable, and understanding them helps you make better material choices.
Aged Solar Reflectance
The fraction of solar radiation the surface reflects rather than absorbing, measured after three years of weathering. Ranges 0 to 1 where higher is cooler. The 2026 low-slope minimum is 0.63. Initial reflectance is often 0.1 to 0.2 higher than aged reflectance because of weathering and soiling.
Thermal Emittance
The efficiency with which the surface radiates absorbed heat back to the sky. Ranges 0 to 1. Most non-metallic surfaces (asphalt, tile, membranes) have emittance around 0.85-0.90. Bare metal has emittance around 0.05-0.10, which is why metal roofs typically require a low-emissivity coating to meet the 0.75 threshold.
Solar Reflectance Index (SRI)
A composite metric combining reflectance and emittance into one number. Ranges from 0 (standard black surface) to 100 (standard white surface), with high-performing cool surfaces exceeding 100. The 2026 low-slope minimum is approximately 75, achievable via 0.63 aged reflectance + 0.75 emittance.
See a Title 24-Compliant Roof Estimate
Get an instant quote from California contractors who specify CRRC-listed cool products and handle CF1R/CF2R compliance documentation.
Interactive 2026 Title 24 Compliance Tool
Enter your project details to see whether the 2026 update applies, what SRI minimum you need, and which trade-off paths are available.
2026 Title 24 Cool Roof Compliance Checker
Check whether your California re-roof triggers the 2025 Title 24 update (effective January 1, 2026) and what minimum SRI and qualifying materials apply.
Sacramento, Stockton, Modesto
Steep-slope prescriptive tightened to CZ 2-15 under the 2025 update, with stricter values in CZ 10-14.
The 2025 update lowered the tear-off + deck-repair threshold and pulled more recovers into scope.
Select what you are planning to install (or what is already on the roof).
Triggers Title 24 compliance?
Yes — 2025 update applies
Full replacement triggers Title 24 Part 6 compliance at the CF1R permit stage.
Min Aged Solar Reflectance
0.25
Min Thermal Emittance
0.75
Min SRI
23
Qualifying CRRC-Listed Materials for This Profile
- Cool-rated asphalt shingles: GAF Timberline Cool Series, Owens Corning Duration Cool Plus, CertainTeed Landmark Solaris / Solaris Platinum
- Concrete tile — most mid-to-light colors from Eagle, Boral / Westlake Royal, US Tile meet aged SR ≥ 0.20 naturally
- Clay tile — standard terracotta and lighter glazed colors are CRRC-listed
- Stone-coated metal: DECRA Cool, Boral Steel Cool Roof line
- Standing-seam metal with factory Kynar 500 cool pigment coatings (Sherwin-Williams Fluropon Cool, PPG Duranar Sunstorm)
Alternative: Insulation Trade-Off Path
CZ 10-14 steep-slope trade-off: if you keep a dark non-cool roof, you must add R-38 attic insulation plus a compliant radiant barrier, or upgrade to continuous R-10 above-deck rigid insulation. Model through CBECC-Res 2025 and document on CF1R.
Estimated Cost Premium
$0.75 – $2.00 / sqft premium typical in CZ 10-14 for cool-rated shingle vs standard dark shingle.
Values reflect the 2025 Building Energy Efficiency Standards (Title 24 Part 6) effective January 1, 2026. Compliance is documented on the CF1R (design), CF2R (installer), and CF3R (HERS rater, when required) forms at permit. Local amendments may impose stricter values — verify with your building department and the California Energy Commission.
Get Instant 2026-Compliant Quotes for Your California Roof →Prescriptive vs Performance Compliance Paths
Title 24 allows two paths to compliance. Understanding both helps you pick the material you actually want while still passing permit.
Prescriptive Path
Select a Cool Roof Rating Council (CRRC) listed product that meets the specific aged reflectance and emittance minimums for your climate zone and roof slope. This is the simpler path and is what most residential projects use. Material premium versus non-cool products typically runs $0.50-$2.00 per square foot installed.
Performance (Trade-Off) Path
Meet an overall envelope energy-performance budget through compensating measures. Common trade-offs include adding R-5 to R-10 of attic insulation above prescriptive minimum, installing a radiant barrier under the roof deck, adding above-deck continuous insulation, or improving attic ventilation. The calculation runs through a CEC-approved software package (CBECC-Res or EnergyPro) and is documented on CF1R. Expect $200-800 in Title 24 consultant fees for this path.
CF1R, CF2R, CF3R Documentation
Compliance is documented through three Certificate of Compliance forms, each with a specific timing and responsible party:
- • CF1R (Certificate of Compliance): Prepared before permit. Documents the compliance pathway (prescriptive or performance) and specifies the product. Responsible party: designer, contractor, or Title 24 consultant.
- • CF2R (Certificate of Installation): Prepared after installation. Verifies that the installed product matches the CF1R specification. Responsible party: installing contractor.
- • CF3R (Certificate of Verification): Required only for certain performance-path submittals. Completed by a third-party HERS rater who field-verifies specific measures. Responsible party: certified HERS rater.
All forms are submitted to the local building department through the permit portal. Keep copies in your permanent home records; future buyers and insurers often request them.
Stacking Title 24 Compliance with Rebates
Meeting Title 24 is code-required. Several stackable rebate programs reward exceeding the minimum or bundling with other upgrades:
- • Utility IOU rebates: PG&E, SCE, SDG&E cool-roof programs pay $0.10-$0.30 per square foot for high-SRI roofs exceeding prescriptive minimum
- • AB 888 Safe Homes Act: If your property is in an FHSZ, fire-rated + cool-rated roofs can draw from the $40K AB 888 cap
- • CoolCalifornia rebates: State-administered incentives for verified cool-roof installations
- • Local municipal programs: Cities including Los Angeles (LADWP), San Francisco, and Sacramento (SMUD) offer additional utility-side rebates
Frequently Asked Questions
Frequently Asked Questions
What changed in the 2025 Title 24 cool roof update effective 2026?
The 2025 Building Energy Efficiency Standards (Title 24 Part 6), effective January 1, 2026, tightened cool-roof performance thresholds and expanded which project types trigger compliance. Key changes: (1) Low-slope (flat or near-flat) roofs now require minimum aged solar reflectance of 0.63 and thermal emittance of 0.75, corresponding to a Solar Reflectance Index (SRI) of approximately 75. (2) Steep-slope roofs in hot climate zones (particularly CZ 10-14 covering the Central Valley and Inland Empire) require higher aged reflectance under the prescriptive path. (3) The scope threshold that triggers compliance was lowered: more tear-off and deck-repair projects now qualify as "alterations" that must meet cool-roof minimums rather than being treated as like-for-like replacements. (4) The SRI-path alternative and insulation trade-off path remain available, but calculation documentation (CF1R, CF2R, CF3R forms) is more rigorously enforced at permit time.
Does my re-roof project trigger Title 24 compliance under the 2026 rules?
Yes in most cases. Under the 2025 update, any roof replacement project that involves a full tear-off plus deck repair exceeding minor localized patches now triggers full Title 24 cool-roof compliance, regardless of whether you previously had a cool-rated surface. Recover projects (installing a new surface over an existing roof) generally trigger compliance when they affect more than 50 percent of the roof area. Like-for-like repair of a small leak or limited section replacement below roughly 300 square feet typically does not trigger compliance. Climate zone matters: CZ 1 (coastal far north) and CZ 16 (high mountain) have limited cool-roof requirements because heating loads dominate; CZ 2-15 have progressively stricter requirements as cooling loads dominate, with CZ 10-14 carrying the tightest steep-slope thresholds.
What is SRI and what level do I need for 2026 compliance?
Solar Reflectance Index (SRI) is a composite metric that combines solar reflectance (how much sunlight the surface reflects rather than absorbing) and thermal emittance (how efficiently the surface radiates absorbed heat back to the sky). It is expressed as a single number between roughly 0 and 100+ where higher is cooler. Under the 2025 Title 24 update, low-slope roofs need a minimum SRI of approximately 75, achievable via aged reflectance of 0.63 paired with emittance of 0.75. Steep-slope roofs in hot climate zones require lower SRI minimums (roughly 10-16 aged, depending on zone) because darker visible surfaces are compatible with cooling targets if the product is specifically cool-rated. The Cool Roof Rating Council (CRRC) maintains a searchable product database with tested SRI values; your contractor or product supplier references this list to select compliant materials.
How do I prove cool roof compliance for the building permit?
Title 24 compliance is documented through three forms in the CF series. (1) CF1R (Certificate of Compliance) is prepared before permit issuance by the designer or contractor and documents the intended compliance pathway (prescriptive, performance, or trade-off). (2) CF2R (Certificate of Installation) is completed by the installing contractor after the work is done, verifying that the installed product matches the CF1R specification. (3) CF3R (Certificate of Verification) is required for specific performance-path submittals and is completed by a third-party HERS (Home Energy Rating System) rater. For typical residential re-roof projects on the prescriptive path, the CF1R and CF2R are the required forms, and both are submitted to the local building department as part of permit inspection. Your CRRC-listed product specification sheet is the supporting document that ties installed material to SRI claim.
What if my chosen material does not meet SRI requirements? Can I trade off with insulation?
Yes. The 2025 Title 24 code continues to allow both the prescriptive path (hit the specific SRI minimum) and the performance / trade-off path (meet an overall energy budget through compensating measures). If your preferred roofing material does not meet the prescriptive SRI minimum, the most common trade-off is additional attic insulation. Adding R-5 to R-10 above prescriptive minimum can often compensate for a 10-15 SRI deficit on the roof surface, depending on climate zone and overall envelope performance. Radiant barriers, added attic ventilation, and above-deck continuous insulation are also trade-off options. The calculation is run through a CEC-approved compliance software package (CBECC-Res or EnergyPro) and documented on the CF1R. Your Title 24 consultant or experienced roofing contractor handles this during permit prep. Expect $200-800 in compliance documentation cost for any trade-off pathway.
Do 2026 Title 24 cool roof requirements apply to tile roofs?
Yes, with nuance. Clay and concrete tile are naturally cooler than dark asphalt because of tile geometry and color choices, but only CRRC-listed cool-rated tile products carry verified SRI values adequate for prescriptive compliance. Standard terracotta clay tile often meets steep-slope CZ 2-9 thresholds without special treatment; Spanish-color and red concrete tile in CZ 10-14 may require cool-rated pigment versions (Eagle Roofing, Boral, Westile all offer cool-rated lines). Dark charcoal and slate-gray concrete tile typically require the trade-off path in hot zones. The good news for tile is that its inherent thermal mass and ventilation under-tile airspace provide additional cooling benefit that the prescriptive SRI metric does not fully capture, which is why trade-off calculations for tile roofs tend to show strong overall envelope performance even when surface SRI is below prescriptive minimum.