CALGreen · California Green Building Standards Code (CALGreen)

Cool roofs, solar reflectance and heat island reduction measures

CALGreen requires nonresidential projects to use cool roofs that meet minimum **aged solar reflectance** and **thermal emittance** (or an **SRI**) based on roof slope and tier; exceptions include heavy thermal‑mass roofs and areas under building‑integrated solar, and the code provides an equation and SRI worksheet method to handle missing aged ratings.

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Last reviewed: July 6, 2026

What the code requires — plain English

The code gives three ways to reduce heat-island effect: hardscape alternatives, cool roofs, or shade trees; cool roofs are specifically regulated by § A5.106.11.2 and may be met either by minimum aged solar reflectance + thermal emittance or by meeting a minimum Solar Reflectance Index (SRI) in § A5.106.11.2.3. These cool‑roof requirements are organized for Tier 1 and Tier 2 compliance and include narrow exceptions (for heavy thermal-mass roofs and areas covered by building‑integrated PV/thermal) .

The single most important rule: pick roofing materials that meet the minimum aged solar reflectance and thermal emittance (or the minimum SRI) specified for your roof slope and tier — otherwise the assembly does not qualify as a “cool roof” under CALGreen (§ A5.106.11.2).

Requirements in detail

  • Bolded defined terms on first mention: aged solar reflectance, thermal emittance, Solar Reflectance Index (SRI), Cool Roof Rating Council (CRRC), and § A5.106.11.2 / § A5.106.11.2.3. These are the control points in the code text.

What must be demonstrated

  • Roofing materials must either:
    • Meet minimum aged solar reflectance and thermal emittance values (see Tier tables), or
    • Meet minimum SRI values calculated using the Energy Commission SRI worksheet or ASTM E1980 (the SRI alternative) as allowed in § A5.106.11.2.3.
  • If CRRC 3‑year aged test data aren’t available, the code provides a method to estimate aged reflectance from the CRRC initial value using the prescribed equation and product‑type soiling resistance (β).
  • The SRI used for compliance must be calculated with the California Energy Commission’s SRI worksheet or meet ASTM E1980, using the aged reflectance (or the calculated aged value) and a certified thermal emittance (initial or aged).

Decision table — roof slope, climate zone and minimum values

Tier Roof slope Climate zone(s) Minimum aged solar reflectance Minimum thermal emittance Minimum SRI Code Reference
Tier 1 ≤ 2:12 (low-slope) 1–16 0.63 0.75 75 § A5.106.11.2 / Table A5.106.11.2.2
Tier 1 > 2:12 (steep) 1–16 0.20 0.75 16 § A5.106.11.2 / Table A5.106.11.2.2
Tier 2 ≤ 2:12 (low-slope) 1–16 0.68 0.85 82 § A5.106.11.2.3 / Table A5.106.11.2.3
Tier 2 > 2:12 (steep) 1–16 0.28 0.85 27 § A5.106.11.2.3 / Table A5.106.11.2.3

Notes on the table:

  • The slope break is ≤ 2:12 versus > 2:12 — that threshold changes which set of minimums apply.
  • SRI is an alternative compliance path; you may use SRI instead of separate reflectance + emittance requirements as described in § A5.106.11.2.3.

How to handle missing aged CRRC ratings

  • If no CRRC aged rating exists, calculate ρ_aged using the code equation ρ_aged = 0.2 + β(ρ_initial − 0.2), where β is the soiling‑resistance factor (β = 0.65 for field‑applied coatings; 0.70 for other products) as given in § A5.106.11.2.1.

Verification

  • If documentation is missing, the enforcing agency must inspect roofing materials to confirm aged solar reflectance and thermal emittance or SRI compliance per § A5.106.11.2.4. The SRI must be calculated with the Energy Commission worksheet or ASTM E1980 methods.

Exceptions & special cases

  • The following roof areas are exempt from cool‑roof minimums (you do NOT have to meet the reflectance/emittance/SRI for these):
    • Roof constructions with a thermal mass over the roof membrane weighing at least 25 pounds per square foot (for example, heavy overburden or a substantial vegetated roof). § A5.106.11.2 Exception 1.
    • Roof areas covered by building‑integrated photovoltaic (PV) or building‑integrated solar thermal panels. § A5.106.11.2 Exception 2.
  • Tier requirements: cool‑roof values are called out for both Tier 1 and Tier 2 programs; Tier 2 requires more stringent values (see Table A5.106.11.2.3). Compliance with tier obligations is enforced by the Tier sections (e.g., § A5.601.2 / § A5.601.3).
  • The code allows supervisory entities approved by the Energy Commission to certify solar reflectance/thermal emittance values as an alternative to CRRC data. § A5.106.11.2.1 / § A5.106.11.2.2.

Common mistakes

  • Using initial solar reflectance numbers instead of aged values (or failing to apply the code’s aged‑value equation when CRRC aged ratings aren’t available). The code requires aged values or the equation in § A5.106.11.2.1.
  • Applying the low‑slope values to steep roofs (or vice versa). The ≤ 2:12 threshold matters for which minima apply.
  • Forgetting the thermal-mass or BIPV exceptions and measuring those areas for compliance unnecessarily. § A5.106.11.2 exceptions list both exemptions.
  • Using an SRI value computed without the Energy Commission’s worksheet or ASTM E1980 method; the code specifically requires the SRI calculation method in § A5.106.11.2.3.
  • Failing to retain documentation or to allow inspection: § A5.106.11.2.4 requires verification where documentation isn’t available.

Worked example — concrete scenario

Scenario: New nonresidential building, low‑slope roof (≤ 2:12) in Climate Zone 10, pursuing Tier 1 compliance.

  1. Identify the Tier 1 minimums for this slope/zone: aged solar reflectance 0.63 and thermal emittance 0.75 (or SRI 75) per § A5.106.11.2 / Table A5.106.11.2.2.
  2. Product selection:
    • Product A has CRRC certified initial solar reflectance = 0.80 and either (a) a CRRC 3‑year aged reflectance listed as 0.66 (certified) — that meets the 0.63 aged requirement, and thermal emittance listed at 0.78 (meets 0.75). That product complies.
    • If Product B only has an initial value (no aged CRRC), compute aged reflectance using the code equation: ρ_aged = 0.2 + β(ρ_initial − 0.2). For a factory‑applied sheet product (β = 0.70) with ρ_initial = 0.80, then ρ_aged = 0.2 + 0.70(0.80 − 0.2) = 0.2 + 0.70(0.60) = 0.2 + 0.42 = 0.62. That would not meet the Tier 1 low‑slope aged requirement of 0.63. Use the CRRC aged rating or a different product. § A5.106.11.2.1.
  3. SRI alternative: You could instead show the product has SRI ≥ 75 calculated using the Energy Commission SRI worksheet (using the aged reflectance you have or the equation‑derived aged value, and certified emittance) per § A5.106.11.2.3 and SRI‑WS guidance.
  4. Documentation: retain CRRC reports or SRI worksheet output and be prepared for inspection under § A5.106.11.2.4.

Related CALGreen provisions

  • § A5.106.11.1 — Hardscape alternatives for heat‑island reduction (light‑colored or permeable paving options).
  • § A5.106.11.2 — Cool roof general requirement and tables for Tier 1 values (see tables and exceptions).
  • § A5.106.11.2.3 — SRI alternative and SRI calculation worksheet requirement (Tier 2 table shown there).
  • § A5.106.11.2.4 — Verification of compliance (inspection where documentation is missing).
  • § A5.106.11.3 — Shade tree option; where no local ordinance exists, comply with the specified shade tree requirements.
  • § A5.601.2 and § A5.601.3 — Tier 1 and Tier 2’’s lists of required voluntary measures that call out cool‑roof compliance as a Tier prerequisite.

Code references

Grounded in the retrieved California Green Building Standards Code (CALGreen) — click a citation to read the verbatim passage:

  • CALGreen § 106.7.1 High relevance — show source text

    A5.106.7.1 Fenestration. Provide vegetative or man-made shading devices for all fenestration on east-, south- and west-facing walls.

    A5.106.7.1.1 East and west walls. Shading devices shall have 30-percent coverage to a height of 20 feet or to the top of the exterior wall, whichever is less. Calculate shade coverage on the summer solstice at 10 AM for east-facing walls and at 3 PM for west-facing walls.

    A5.106.7.1.2 South walls. Shading devices shall have 60-percent coverage to a height of 20 feet or to the top of the exterior wall, whichever is less.

    A5.106.7.2 Opaque wall areas. Use wall surfacing with minimum SRI 25 (aged), for 75 percent of opaque wall areas.

    Exception: Use of vegetated shade in Wildland-Urban Interface Areas as defined in Chapter 7A (Materials and Construction Methods for Exterior Wildfire Exposure) of the California Building Code shall meet the requirements of that chapter.

    Note: If not available from the manufacturer, aged SRI value calculations may be found at the California Energy Commis-sion’s web site at www.energy.ca.gov.

    A5.106.8 Reserved.

    A5.106.9 Reserved.

    A5.106.10 Reserved.

    A5.106.11 Reduction of heat island effect. Reduce heat islands by requiring Section A5.106.11.1 Hardscape alternatives, Section A5.106.11.2 Cool roofs, or Section A5.106.11.3 Shade trees.

    A5.106.11.1 Hardscape alternatives. Use one or a combination of strategies 1 and 2 for 50 percent of site hardscape or put 50 percent of parking underground.

    1. Use light colored materials with an initial solar reflectance value of at least 0.30 as determined in accordance with American Society for Testing and Materials (ASTM) Standards E1918 or C1549.
    2. Use open-grid pavement system or pervious or permeable pavement system.

    APPENDIX A5-8 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    APPENDIX A5 — NONRESIDENTIAL VOLUNTARY MEASURES

    A5.106.11.2 Cool roof. Use roofing materials having a minimum aged solar reflectance and thermal emittance complying with Sections A5.106.11.2.1 and A5.106.11.2.2 or a minimum aged Solar Reflectance Index (SRI) complying with Section A5.106.11.2.3 and as shown in Table A5.106.11.2.2 for Tier 1 or Table A5.106.11.2.3 for Tier 2.

    Exceptions:

    1. Roof constructions that have a thermal mass over the roof membrane, including areas of vegetated (green) roofs, weighing at least 25 pounds per square foot.
    2. Roof area covered by building integrated solar photovoltaic and building integrated solar thermal panels.

    A5.106.11.2.1 Solar reflectance. Roofing materials shall have a minimum aged solar reflectance equal to or greater than the values specified in Table A5.106.11.2.2 for Tier 1 and Table A5.106.11.2.3 for Tier 2.

  • CALGreen § 106.11.2 High relevance — show source text

    APPENDIX A5-8 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    APPENDIX A5 — NONRESIDENTIAL VOLUNTARY MEASURES

    A5.106.11.2 Cool roof. Use roofing materials having a minimum aged solar reflectance and thermal emittance complying with Sections A5.106.11.2.1 and A5.106.11.2.2 or a minimum aged Solar Reflectance Index (SRI) complying with Section A5.106.11.2.3 and as shown in Table A5.106.11.2.2 for Tier 1 or Table A5.106.11.2.3 for Tier 2.

    Exceptions:

    1. Roof constructions that have a thermal mass over the roof membrane, including areas of vegetated (green) roofs, weighing at least 25 pounds per square foot.
    2. Roof area covered by building integrated solar photovoltaic and building integrated solar thermal panels.

    A5.106.11.2.1 Solar reflectance. Roofing materials shall have a minimum aged solar reflectance equal to or greater than the values specified in Table A5.106.11.2.2 for Tier 1 and Table A5.106.11.2.3 for Tier 2.

    If Cool Roof Rating Council (CRRC) testing for aged reflectance is not available for any roofing products, the aged value shall be determined using the CRRC certified initial value using the equation ρ aged = [0.2 + ß [ρ initial – 0.2], where ρ initial = the initial solar reflectance and soiling resistance, ß, listed by product type in Table A5.106.11.2.1.

    Solar reflectance may also be certified by other supervisory entities approved by the Energy Commission pursuant to Title 24, Part 1, California Administrative Code.

    TABLE A5.106.11.2.1—VALUES OF SOILING RESISTANCE, ß, BY PRODUCT TYPE Col2 Col3
    PRODUCT TYPE CRRC PRODUCT CATEGORY ß
    Field-applied coating Field-applied coating 0.65
    Other Not a field-applied coating 0.70

    A5.106.11.2.2 Thermal emittance. Roofing materials shall have a CRRC initial or aged thermal emittance as determined in accordance with ASTM E408 or C1371 equal to or greater than those specified in Table A5.106.11.2.2 for Tier 1 and Table A5.106.11.2.3 for Tier 2.

    Thermal emittance may also be certified by other supervisory entities approved by the Energy Commission pursuant to Title 24, Part 1, California Administrative Code.

    TABLE A5.106.11.2.2 [BSC]—TIER 1 Col2 Col3 Col4 Col5
    ROOF SLOPE CLIMATE ZONE MINIMUM AGED SOLAR REFLECTANCE THERMAL EMITTANCE SRI
    ≤ 2:12 1–16 0.63 0.75 75
    > 2:12 1–16 0.20 0.75 16
  • CALGreen § 106.2.3 High relevance — show source text

    A4.106.2.3 Topsoil protection. Topsoil shall be protected or saved for reuse as specified in this section.

    Tier 1. Displaced topsoil shall be stockpiled for reuse in a designated area and covered or protected from erosion.

    Note: Protection from erosion includes covering with tarps, straw, mulch, chipped wood, vegetative cover or other means acceptable to the enforcing agency to protect the topsoil for later use.

    Tier 2. The construction area shall be identified and delineated by fencing or flagging to limit construction activity to the construction area. Heavy equipment or vehicle traffic and material storage outside the construction area shall be limited to areas that are planned to be paved.

    A4.106.3 Landscape design. Postconstruction landscape designs shall accomplish one or more of the following:

    1. Areas disrupted during construction are restored to be consistent with native vegetation species and patterns.
    2. Utilize at least 75 percent native California or drought tolerant plant and tree species appropriate for the climate zone region.

    A4.106.4 Water permeable surfaces. Permeable paving is utilized for the parking, walking or patio surfaces in compliance with the following.

    Tier 1. Not less than 20 percent of the total parking, walking or patio surfaces shall be permeable.

    APPENDIX A4-4 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE

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    APPENDIX A4 — RESIDENTIAL VOLUNTARY MEASURES

    Tier 2. Not less than 30 percent of the total parking, walking or patio surfaces shall be permeable.

    Exceptions:

    1. The primary driveway, primary entry walkway and entry porch or landing shall not be included when calculating the area required to be a permeable surface.
    2. Required accessible routes for persons with disabilities as required by California Code of Regulations, Title 24, Part 2, Chapter 11A and/or Chapter 11B as applicable.

    A4.106.5 Cool roof for reduction of heat island effect. Roofing materials for Tier 1 and Tier 2 buildings shall comply with this section:

    Exceptions:

    1. Roof constructions that have a thermal mass over the roof membrane including areas of vegetated (green) roofs, weighing at least 25 pounds per square foot.
    2. Roof areas covered by building integrated solar photovoltaic panels and building integrated solar thermal panels.

    A4.106.5.1 Solar reflectance. Roofing materials shall have a minimum 3-year aged solar reflectance equal to or greater than the values specified in Tables A4.106.5.1(1) and A4.106.5.1(3) for Tier 1 and Tables A4.106.5.1(2) and A4.105.5.1(4) for Tier 2.

    If CRRC testing for aged solar reflectance is not available for any roofing products, the aged value shall be determined using the Cool Roof Rating Council (CRRC) certified initial value using the equation ρ aged = [0.2 + β[ρ initial -0.2], where ρ initial = the initial Solar Reflectance and soiling resistance, β, is listed by product type in Table A4.106.5.1.

    Solar reflectance may also be certified by other supervisory entities approved by the Energy Commission pursuant to Title 24, Part 1, Section 10-113.

  • CALGreen § 405.4 High relevance — show source text
    1. From Division A5.4,

    a. Comply with recycled content of 10 percent of materials based on estimated total cost, or use two products from Table A5.405.4 for at least 75 percent by cost in Section A5.405.4. b. Comply with the 65-percent reduction in construction and demolition waste in Section A5.408.3.1. c. Comply with one elective measure selected from this division.

    1. From Division A5.5,

    a. Comply with resilient flooring systems for 90 percent of resilient flooring in Section A5.504.4.7. b. Comply with thermal insulation meeting 2009 CHPS low-emitting materials list in Section A5.504.4.8. c. Comply with one elective measure selected from this division. 6. Comply with one additional elective measure selected from any division.

    1 Cool roof is required for compliance with Tiers 1 and 2 and may be used to meet energy standards in Part 6, exceed energy standards and to mitigate heat island effect.

    A5.601.3 CALGreen Tier 2.

    A5.601.3.1 Prerequisites. To achieve CALGreen tier status, a project must meet all of the mandatory measures in Chapter 5 and, in addition, meet the provisions of this section.

    A5.601.3.2 Energy performance. For the purposes of mandatory energy efficiency standards in this code, the California Energy Commission will continue to adopt mandatory standards.

    A5.601.3.3 Tier 2. Comply with the energy efficiency requirements in Section A5.203.1.1 and Section A5.203.1.2.2.

    A5.601.3.4 Voluntary measures for Tier 2. In addition to the provisions of Sections A5.601.3.1 and A5.601.3.3 above, compliance with the following voluntary measures from Appendix A5 is required for Tier 2:

    1. From Division A5.1, a. Comply with the designated parking requirements for fuel efficient vehicles for a minimum of 50 percent of parking capacity per Section A5.106.5.1. b. Electric vehicle (EV) charging [N] and Table A5.106.5.3.2 with footnotes. c. Comply with thermal emittance, solar reflectance or SRI values for cool roofs in Section A5.106.11.2 and Table A5.106.11.2.3. [1]

    d. Comply with three elective measures selected from this division.

    APPENDIX A5-42 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    APPENDIX A5 — NONRESIDENTIAL VOLUNTARY MEASURES

    1. From Division A5.2 comply with TWO of the following:

    2. Outdoor lighting as described in A5.203.1.1.1.

    3. Service water heating in restaurants as described in A5.203.1.1.2.

    4. Warehouse Dock Seal Doors A5.203.1.1.3.

    5. Daylight Design Power Adjustments 5.203.1.1.4.

    6. Exhaust Air Heat Recovery A5.203.1.1.5.

    7. From Division A5.3,

  • CALGreen § 106.5 High relevance — show source text

    Exceptions:

    1. The primary driveway, primary entry walkway and entry porch or landing shall not be included when calculating the area required to be a permeable surface.
    2. Required accessible routes for persons with disabilities as required by California Code of Regulations, Title 24, Part 2, Chapter 11A and/or Chapter 11B as applicable.

    A4.106.5 Cool roof for reduction of heat island effect. Roofing materials for Tier 1 and Tier 2 buildings shall comply with this section:

    Exceptions:

    1. Roof constructions that have a thermal mass over the roof membrane including areas of vegetated (green) roofs, weighing at least 25 pounds per square foot.
    2. Roof areas covered by building integrated solar photovoltaic panels and building integrated solar thermal panels.

    A4.106.5.1 Solar reflectance. Roofing materials shall have a minimum 3-year aged solar reflectance equal to or greater than the values specified in Tables A4.106.5.1(1) and A4.106.5.1(3) for Tier 1 and Tables A4.106.5.1(2) and A4.105.5.1(4) for Tier 2.

    If CRRC testing for aged solar reflectance is not available for any roofing products, the aged value shall be determined using the Cool Roof Rating Council (CRRC) certified initial value using the equation ρ aged = [0.2 + β[ρ initial -0.2], where ρ initial = the initial Solar Reflectance and soiling resistance, β, is listed by product type in Table A4.106.5.1.

    Solar reflectance may also be certified by other supervisory entities approved by the Energy Commission pursuant to Title 24, Part 1, Section 10-113.

    TABLE A4.106.5.1—VALUES OF SOILING RESISTANCE (ß) BY PRODUCT TYPE Col2 Col3
    PRODUCT TYPE CCRC PRODUCT CATEGORY ß
    Field-applied coating Field-applied coating 0.65
    Other Not a field-applied coating 0.70

    A4.106.5.2 Thermal emittance. Roofing materials shall have a CRRC initial or aged thermal emittance equal to or greater than those specified in Tables A4.106.5.1(1) and A4.106.5.1(3) for Tier 1 and Tables A4.106.5.1(2) and A4.106.5.1(4) for Tier 2.

    Thermal emittance may also be certified by other supervisory entities approved by the Energy Commission pursuant to Title 24, Part 1, California Administrative Code.

    A4.106.5.3 Solar reflectance index alternative. Solar Reflectance Index (SRI) equal to or greater than the values specified in Tables A4.106.5.1(1) and A4.106.5.1(3) for Tier 1 and Tables A4.106.5.1(2) and A4.106.5.1(4) for Tier 2 may be used as an alternative to compliance with the 3-year aged solar reflectance values and thermal emittance.

  • CALGreen § 106.5.4 High relevance — show source text

    APPENDIX A4 — RESIDENTIAL VOLUNTARY MEASURES

    A4.106.5.4 Verification. Inspection shall be conducted to ensure roofing materials meet cool roof aged solar reflectance and thermal emittance or SRI values.

    A4.106.6 Vegetated roof. Install a vegetated roof for at least 50 percent of the roof area. Vegetated roofs shall comply with requirements for roof gardens and landscaped roofs in the California Building Code, Chapter 15 and Chapter 16.

    A4.106.7 Reduction of heat island effect for nonroof areas. Reduce nonroof heat islands for 50 percent of sidewalks, patios, driveways or other paved areas by using one or more of the methods listed.

    1. Trees or other plantings to provide shade and that mature within 15 years of planting. Trees should be native or adaptive to the region and climate zones and noninvasive; hardy and resistant to drought, insects and disease; easy to maintain (no frequent shedding of twigs, branches, unwanted fruit or seed pods); and suitable in mature size and environmental requirements for the site. Tree selection and placement should consider location and size of areas to be shaded, location of utilities, views from the structure, distance to sidewalks and foundations, overhangs onto adjacent properties and streets; other infrastructure and adjacent to landscaping. In addition, shading shall not cast a shadow, as specified, on any neighboring solar collectors pursuant to Public Resources Code Section 25981, et seq. (Solar Shade Control Act).
    2. Use high albedo materials with an initial solar reflectance value of at least 0.30 as determined in accordance with American Society for Testing and Materials (ASTM) Standards E1918 or C1549.
    3. Use open grid pavement system or pervious or permeable pavement system.
    4. Locate 50 percent of parking underground or use multilevel parking.
    5. Other methods of reducing heat island effects acceptable to the enforcing agency.

    Note: Local agencies may have ordinances requiring mitigation of heat island effects through building or parking lot shading, tree plantings, landscaping, use of pervious pavements and other approved methods.

    A4.106.8 Electric vehicle (EV) charging for new construction. New construction shall comply with Section A4.106.8.1 or A4.106.8.2, to facilitate the installation and use of EV ready spaces. Electric vehicle supply equipment (EVSE) shall comply with the California Electrical Code .

    A4.106.8.1 New one- and two-family dwellings and townhouses with attached private garages.

    Tier 1 and Tier 2. For each dwelling unit, a dedicated 208/240-volt branch circuit shall be installed in the raceway required by Section 4.106.4.1. The branch circuit and associated overcurrent protective device shall be rated at 40 amperes minimum. Other electrical components, including a receptacle or blank cover, related to this section shall be installed in accordance with the California Electrical Code.

    A4.106.8.1.1 Identification. The service panel or subpanel circuit directory shall identify the overcurrent protective device designated for future EV charging purposes as “EV READY” in accordance with the California Electrical Code. The receptacle or blank cover shall be identified as “EV READY.”

    A4.106.8.2 New multifamily dwellings, hotels and motels. New multifamily dwellings, hotels and motels shall meet the following requirements.

  • CALGreen § 601.2.4 High relevance — show source text

    A5.601.2.4 Voluntary measures for Tier 1. In addition to the provisions of Sections A5.601.2.1 and A5.601.2.3 above, compliance with the following voluntary measures from Appendix A5 is required for Tier 1:

    1. From Division A5.1, a. Comply with the designated parking requirements for high-efficiency vehicles for a minimum of 35 percent of parking capacity per Section A5.106.5.1. b. Electric vehicle (EV) charging [N] and Table A5.106.5.3.1 w/ footnotes. c. Comply with thermal emittance, solar reflectance or SRI values for cool roofs in Section A5.106.11.2 and Table A5.106.11.2.2. [1]

    d. Comply with one elective measure selected from this division. 2. From Division A5.2 comply with ONE of the following:

    1. Outdoor lighting as described in A5.203.1.1.1.

    2. Service water heating in restaurants as described in A5.203.1.1.2.

    3. Warehouse Dock Seal Doors A5.203.1.1.3.

    4. Daylight Design Power Adjustments 5.203.1.1.4.

    5. Exhaust Air Heat Recovery A5.203.1.1.5.

    6. From Division A5.3,

    a. Comply with the 12-percent reduction for indoor potable water use in Section A5.303.2.3.1. b. Comply with one elective measure selected from this division.

    1. From Division A5.4,

    a. Comply with recycled content of 10 percent of materials based on estimated total cost, or use two products from Table A5.405.4 for at least 75 percent by cost in Section A5.405.4. b. Comply with the 65-percent reduction in construction and demolition waste in Section A5.408.3.1. c. Comply with one elective measure selected from this division.

    1. From Division A5.5,

    a. Comply with resilient flooring systems for 90 percent of resilient flooring in Section A5.504.4.7. b. Comply with thermal insulation meeting 2009 CHPS low-emitting materials list in Section A5.504.4.8. c. Comply with one elective measure selected from this division. 6. Comply with one additional elective measure selected from any division.

    1 Cool roof is required for compliance with Tiers 1 and 2 and may be used to meet energy standards in Part 6, exceed energy standards and to mitigate heat island effect.

    A5.601.3 CALGreen Tier 2.

    A5.601.3.1 Prerequisites. To achieve CALGreen tier status, a project must meet all of the mandatory measures in Chapter 5 and, in addition, meet the provisions of this section.

    A5.601.3.2 Energy performance. For the purposes of mandatory energy efficiency standards in this code, the California Energy Commission will continue to adopt mandatory standards.

    A5.601.3.3 Tier 2. Comply with the energy efficiency requirements in Section A5.203.1.1 and Section A5.203.1.2.2.

  • CALGreen § 601.3.4 High relevance — show source text

    A5.601.3.4 Voluntary measures for Tier 2. In addition to the provisions of Sections A5.601.3.1 and A5.601.3.3 above, compliance with the following voluntary measures from Appendix A5 is required for Tier 2:

    1. From Division A5.1, a. Comply with the designated parking requirements for fuel efficient vehicles for a minimum of 50 percent of parking capacity per Section A5.106.5.1. b. Electric vehicle (EV) charging [N] and Table A5.106.5.3.2 with footnotes. c. Comply with thermal emittance, solar reflectance or SRI values for cool roofs in Section A5.106.11.2 and Table A5.106.11.2.3. [1]

    d. Comply with three elective measures selected from this division.

    APPENDIX A5-42 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    APPENDIX A5 — NONRESIDENTIAL VOLUNTARY MEASURES

    1. From Division A5.2 comply with TWO of the following:

    2. Outdoor lighting as described in A5.203.1.1.1.

    3. Service water heating in restaurants as described in A5.203.1.1.2.

    4. Warehouse Dock Seal Doors A5.203.1.1.3.

    5. Daylight Design Power Adjustments 5.203.1.1.4.

    6. Exhaust Air Heat Recovery A5.203.1.1.5.

    7. From Division A5.3,

    a. Comply with the 20-percent reduction for indoor potable water use in Section A5.303.2.3.2. b. Comply with three elective measures selected from this division.

    1. From Division A5.4,

    a. Comply with recycled content of 15 percent of materials based on estimated total cost, or use two products from Table A5.405.4 for at least 75 percent by cost in Section A5.405.4.1. b. Comply with the 80-percent reduction in construction and demolition waste in Section A5.408.3.1. c. Comply with three elective measures selected from this division.

    1. From Division A5.5,

    a. Comply with resilient flooring systems for 100 percent of resilient flooring in Section A5.504.4.7.1. Exception: Allowance may be permitted in Tier 2 for up to 5-percent specialty purpose flooring. b. Comply with thermal insulation meeting 2009 CHPS low-emitting materials list and no added formaldehyde in Section A5.504.4.8.1.

    c. Comply with three elective measures selected from this division. 6. Comply with three additional elective measures selected from any division.

    1 Cool roof is required for compliance with Tiers 1 and 2 and may be used to meet energy standards in Part 6, exceed energy standards and to mitigate heat island effect.

    A5.601.4 Compliance verification. Compliance with Section A5.601.2 or A5.601.3 shall be as required in Chapter 7 of this code. Compliance documentation shall be made part of the project record as required in Section 5.410.2 or 5.410.3.

    2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A5-43

  • CALGreen § 110.8 High relevance — show source text

    I. Roofs. Replacements of the exterior surface of existing roofs, including adding a new surface layer on top of the existing exterior surface, shall meet the requirements of Section 110.8 and the applicable requirements of Subsections i and ii where more than 50 percent of the roof is being replaced. i. Steep-sloped roofs. Steep-sloped roofs shall meet the following: New roofing products in Climate Zones 4 and 8 through 15 shall have a minimum aged solar reflectance of 0.20 and a minimum thermal emittance of 0.75, or a minimum SRI of 16. Exception 1 to Section 150.2(b)1Ii: The following shall be considered equivalent to Subsection i: a. Buildings with ceiling assemblies with a U -factor lower than or equal to 0.025 or that are insulated with at least R-38 ceiling insulation; or b. Buildings with a radiant barrier in the attic, where the radiant barrier is not installed directly above spaced sheathing, meeting the requirements of Section 150.1(c)2; or c. In Climate Zones 2, 4, 9, 10, 12 and 14, buildings that have no ducts in the attic; or d. Buildings with R-2 or greater continuous insulation above or below the roof deck. Exception 2 to Section 150.2(b)1Ii: Roof area covered by building integrated photovoltaic panels or building integrated solar thermal panels is not required to meet minimum requirements for aged solar reflectance, thermal emittance or SRI.

    Exception 3 to Section 150.2(b)1Ii: Roof constructions with a weight of at least 25 lb/ft [2] are not required to comply with the minimum requirements for aged solar reflectance and thermal emittance, or SRI. ii. Low-sloped roofs. Low-sloped roofs shall meet the following: a. New roofing products in Climate Zones 4 and 6 through 15 shall have an aged solar reflectance equal to or greater than 0.63 and a thermal emittance equal or greater than 0.75, or a minimum SRI of 75. Exception 1 to Section 150.2(b)1Iiia: The aged solar reflectance can be met by using insulation at the roof deck specified in Table 150.2-E.

    TABLE 150.2-E—AGED SOLAR REFLECTANCE INSULATION TRADE-OFF TABLE Col2 Col3
    MINIMUM AGED
    SOLAR REFLECTANCE    		 ROOF DECK CONTINUOUS INSULATION
    R-VALUE (Climate Zones 6–7)    		 ROOF DECK CONTINUOUS INSULATION
    R-VALUE (Climate Zones 2, 4 and 8–15)
    0.60 2 16
    0.55 4 18
    0.50 6 20
    0.45 8 22
    No requirement 10 24

    Exception 2 to Section 150.2(b)1Iiia: Roof area covered by building integrated photovoltaic panels or building integrated solar thermal panels is not required to meet the minimum requirements for aged solar reflectance, thermal emittance or SRI.

  • CALGreen § 106.5.1 High relevance — show source text

    SRI values used to comply with this section shall be calculated using the Solar Reflectance Index (SRI) Calculation Worksheet (SRI-WS) developed by the California Energy Commission or in compliance with ASTM E1980-01 as specified in the 2022 California Energy Code. Solar reflectance values used in the SRI-WS shall be based on the aged reflectance value of the roofing product or the equation in Section A4.106.5.1 if the CRRC certified aged solar reflectance are not available. Certified thermal emittance used in the SRI-WS may be either the initial value or the aged value listed by the CRRC.

    Solar reflectance and thermal emittance may also be certified by other supervisory entities approved by the Commission pursuant to Title 24, Part 1, California Administrative Code.

    Note: The Solar Reflectance Index Calculation Worksheet (SRI-WS) is available by contacting the Energy Standards Hotline at 1-800-772-3300, website at www.energy.ca.gov or by email at Title24@energy.ca.gov.

    TABLE A4.106.5.1(1)—TIER 1 – LOW-RISE RESIDENTIAL Col2 Col3 Col4 Col5
    ROOF SLOPE CLIMATE ZONE MINIMUM 3-YEAR AGED SOLAR
    REFLECTANCE    		 THERMAL EMITTANCE SRI
    ≤ 2:12 13 & 15 0.63 0.75 75
    > 2:12 10 – 15 0.20 0.75 16
    TABLE A4.106.5.1(2)—TIER 2 – LOW-RISE RESIDENTIAL Col2 Col3 Col4 Col5
    ROOF SLOPE CLIMATE ZONE MINIMUM 3-YEAR AGED SOLAR
    REFLECTANCE    		 THERMAL EMITTANCE SRI
    ≤ 2:12 2, 4, 6 – 15 0.65 0.85 78
    > 2:12 2, 4, 6 – 15 0.23 0.85 20

    2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A4-5

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    TABLE A4.106.5.1(3)—TIER 1 – HIGH-RISE RESIDENTIAL BUILDINGS, HOTELS AND MOTELS Col2 Col3 Col4 Col5
    ROOF SLOPE CLIMATE ZONE MINIMUM 3-YEAR AGED SOLAR
    REFLECTANCE    		 THERMAL EMITTANCE SRI
    ≤ 2:12 9, 10, 11, 13, 14, 15 0.55 0.75 64
    > 2:12 2 – 15 0.20 0.75 16
  • CALGreen § 106.5.1 High relevance — show source text
    TABLE A4.106.5.1(2)—TIER 2 – LOW-RISE RESIDENTIAL Col2 Col3 Col4 Col5
    ROOF SLOPE CLIMATE ZONE MINIMUM 3-YEAR AGED SOLAR
    REFLECTANCE    		 THERMAL EMITTANCE SRI
    ≤ 2:12 2, 4, 6 – 15 0.65 0.85 78
    > 2:12 2, 4, 6 – 15 0.23 0.85 20

    2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A4-5

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    TABLE A4.106.5.1(3)—TIER 1 – HIGH-RISE RESIDENTIAL BUILDINGS, HOTELS AND MOTELS Col2 Col3 Col4 Col5
    ROOF SLOPE CLIMATE ZONE MINIMUM 3-YEAR AGED SOLAR
    REFLECTANCE    		 THERMAL EMITTANCE SRI
    ≤ 2:12 9, 10, 11, 13, 14, 15 0.55 0.75 64
    > 2:12 2 – 15 0.20 0.75 16
    TABLE A4.106.5.1(4)—TIER 2 – HIGH-RISE RESIDENTIAL BUILDINGS, HOTELS AND MOTELS Col2 Col3 Col4 Col5
    ROOF SLOPE CLIMATE ZONE MINIMUM 3-YEAR AGED SOLAR
    REFLECTANCE    		 THERMAL EMITTANCE SRI
    ≤ 2:12 2 – 15 0.65 0.75 78
    > 2:12 2 – 15 0.23 0.75 20

    APPENDIX A4 — RESIDENTIAL VOLUNTARY MEASURES

    A4.106.5.4 Verification. Inspection shall be conducted to ensure roofing materials meet cool roof aged solar reflectance and thermal emittance or SRI values.

    A4.106.6 Vegetated roof. Install a vegetated roof for at least 50 percent of the roof area. Vegetated roofs shall comply with requirements for roof gardens and landscaped roofs in the California Building Code, Chapter 15 and Chapter 16.

    A4.106.7 Reduction of heat island effect for nonroof areas. Reduce nonroof heat islands for 50 percent of sidewalks, patios, driveways or other paved areas by using one or more of the methods listed.

    1. Trees or other plantings to provide shade and that mature within 15 years of planting. Trees should be native or adaptive to the region and climate zones and noninvasive; hardy and resistant to drought, insects and disease; easy to maintain (no frequent shedding of twigs, branches, unwanted fruit or seed pods); and suitable in mature size and environmental requirements for the site.
  • CALGreen § 106.11.2.3 High relevance — show source text

    A5.106.11.2.3 Solar reflectance index alternative. Solar Reflectance Index (SRI) equal to or greater than the values specified in Table A5.106.11.2.2 for Tier 1 and Table A5.106.11.2.3 for Tier 2 may be used as an alternative to compliance with the aged solar reflectance values and thermal emittance.

    SRI values used to comply with this section shall be calculated using the Solar Reflectance Index (SRI) Calculation Worksheet (SRI-WS) developed by the California Energy Commission or in compliance with ASTM E1980-11 as specified in the California Energy Code, Section 110.8(i)3. Solar reflectance values used in the SRI-WS shall be based on the aged reflectance value of the roofing product or the equation in section A5.106.11.2.1 if the CRRC certified aged solar reflectance are not available. Certified Thermal emittance used in the SRI-WS may be either the initial value or the aged value listed by the CRRC.

    Solar reflectance and thermal emittance may also be certified by other supervisory entities approved by the Commission pursuant to Title 24, Part 1, California Administrative Code.

    Note: The Solar Reflectance Index Calculation Worksheet (SRI-WS) is available by contacting the Energy Standard Hotline at 1-800-772-3300, website at www.energy.ca.gov or by email at Title24@ energy.state.ca.us.

    TABLE A5.106.11.2.3 [BSC]—TIER 2 Col2 Col3 Col4 Col5
    ROOF SLOPE CLIMATE ZONE MINIMUM AGED SOLAR REFLECTANCE THERMAL EMITTANCE SRI
    ≤ 2:12 1–16 0.68 0.85 82
    > 2:12 1–16 0.28 0.85 27

    A5.106.11.2.4 Verification of compliance. If no documentation is available, an inspection shall be conducted to ensure roofing materials meet cool roof aged solar reflectance and thermal emittance or SRI values.

    A5.106.11.3 Shade trees. In the absence of a local shade tree ordinance, comply with mandatory Section 5.106.12 Shade trees.

    2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A5-9

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    APPENDIX A5 — NONRESIDENTIAL VOLUNTARY MEASURES

    SECTION A5.107—BIRD-FRIENDLY BUILDING DESIGN

    A5.107 Bird-friendly building design. A newly constructed building, or an alteration of an existing building that includes the addition or replacement of 50 percent or more of the exterior glazing, shall comply with the bird-friendly building design elements and features in Sections A5.107.1 through A5.107.3 of the California Energy Code and the fire hazard severity zone regulations in Chapter 7A of the California Building Code.

    Exception: Alteration to the glazing in historical buildings per the California Historical Building Code .

Frequently asked questions

What is an "aged" solar reflectance and why does CALGreen require it?

Aged solar reflectance is the reflectance value of a roofing product after weathering/soiling (not the initial, brand‑new value). CALGreen requires aged values (or the specified aged estimate equation) because on‑roof performance after exposure is what affects heat‑island and cooling loads (§ A5.106.11.2.1).

Can I use SRI instead of separate reflectance and emittance numbers?

Yes. The code allows using a Solar Reflectance Index (SRI) that meets the table values calculated with the Energy Commission’s SRI worksheet or ASTM E1980 as an alternative per § A5.106.11.2.3.

Are roof areas under solar panels exempt?

Yes. Roof areas covered by building‑integrated photovoltaic or solar thermal panels are listed as exceptions and are not required to meet the cool‑roof minima per § A5.106.11.2 Exception 2.

What if CRRC aged test data don’t exist for my product?

Use the code’s equation to estimate ρ_aged from the CRRC initial value using the product‑type β factor (0.65 for field‑applied coatings; 0.70 for others) in § A5.106.11.2.1.

Does the slope of the roof matter?

Yes. Values differ for low‑slope (≤ 2:12) and steep (> 2:12) roofs — be sure to use the correct row in the applicable table (§ A5.106.11.2 / § A5.106.11.2.3).

Who inspects/verifies compliance?

The enforcing agency inspects where documentation is not available; the code also requires retaining documentation (CRRC reports or SRI worksheet outputs) for verification per § A5.106.11.2.4.

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