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Appendix A5

Section A5.405

California Green Building Standards Code (Title 24, Part 11) · 2019 edition · updated 2026-09-12 · California

MATERIAL SOURCES

A5.405.1 Regional materials. Compared to other products in a given product category, select building materials or products for permanent installation on the project that have been harvested or manufactured in California or within 500 miles of the project site.

  1. For those materials locally manufactured, select materials manufactured using low embodied energy or those that will result in net energy savings over their useful life.

  2. Regional materials shall make up at least 10 percent, based on cost, of total materials value.

  3. If regional materials make up only part of a product, their values are calculated as percentages based on weight.

  4. Provide documentation of the origin, net projected energy savings and value of regional materials.

A5.405.2 Bio-based materials. Select bio-based building materials and products made from solid wood, engineered wood, bamboo, wool, cotton, cork, straw, natural fibers, products made from crops (soy-based, corn-based) and other bio-based materials with at least 50-percent bio-based content.

A5.405.2.1 Certified wood. Certified wood is an important component of green building strategies and the California Building Standards Commission will continue to develop a standard through the next code cycle.

A5.405.2.2 Rapidly renewable materials. Use materials made from plants harvested within a ten-year cycle for at least 2.5 percent of total materials value, based on estimated cost.

A5.405.3 Reused materials. Use salvaged, refurbished, refinished or reused materials for a minimum of 5 percent of the total value, based on estimated cost of materials on the project. Provide documentation as to the respective values.

Note: Sources of some reused materials can be found at CalRecycle. See also Appendix A5, Division A5.1, Section A5.105.1 for on-site materials reuse.

A5.405.4 Recycled content. Use materials, equivalent in performance to virgin materials with a total (combined) recycled content value (RCV) of:

Tier 1. The RCV shall not be less than 10 percent of the total material cost of the project, or use two products which meet the minimum recycled content levels in Table A5.405.4 for at least 75%, by cost, of all products in that category in the project.

Required Total RCV (dollars) = Total Material Cost (dollars) × 10 percent (Equation A5. 4-1)

Tier 2. The RCV shall not be less than 15 percent of the total material cost of the project, or use three products which meet the minimum recycled content levels in Table A5.405.4 for at least 75%, by cost, of all products in that category in the project.

Required Total RCV (dollars) = Total Material Cost (dollars) × 15 percent (Equation A5. 4-2)

For the purposes of this section, materials used as components of the structural frame shall not be used to calculate recycled content. The structural frame includes the load bearing structural elements such as wall studs, plates, sills, columns, beams, girders, joists, rafters and trusses.

Notes:

  1. Sample forms which allow user input and automatic calculation are located at www.hcd.ca.gov/ CALGreen.html and may be used to simplify documenting compliance with this section and for calculating recycled content value of materials or assembly products.

  2. Sources and recycled content of some recycled materials can be obtained from CalRecycle if not provided by the manufacturer.

A5.405.4.1 Total material cost. Total material cost is the total estimated or actual cost of materials and assembly products used in the project. The required total recycled content value for the project (in dollars) shall be determined by Equation A5.4-1 or A5.4-2.

Total material cost shall be calculated by using one of the methods specified below:

  1. Simplified method. To obtain the total cost of the project multiply the square footage of the structure by the square foot valuation established by the enforcing agency. The total material cost is 45 percent of the total cost of the project. Use Equations A5.4-3A or A5.4-3B to determine total material costs using the simplified method.

Total material costs = Project square footage × square foot valuation × 45 percent (Equation A5.4-3A)

Total estimated or actual cost of project × 45 percent (Equation A5.4-3B)

  1. Detailed method. To obtain the total cost of the project, add the estimated and/or actual costs of materials used for the project including the structure (steel, concrete, wood or masonry); the enclosure (roof, windows, doors and exterior walls); the interior walls, ceilings and finishes (gypsum board, ceiling tiles, etc.). The total estimated and/or actual costs shall not include fees, labor and installation costs, overhead, appliances, equipment, furniture or furnishings.

A5.405.4.2 Determination of total recycled content value (RCV). Total RCV may be determined either by dollars or percentage as noted below.

  1. Total recycled content value for the project (in dollars). This is the sum of the recycled content value of the materials and/or assemblies considered and shall be determined by Equation A5.4-4. The result of this calculation may be directly compared to Equations A5.4-1 and A5.4-2 to determine compliance with Tier 1 or Tier 2 prerequisites.

142 2019 CALIFORNIA GREEN BUILDING STANDARDS CODE

Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.

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Total Recycled Content Value (dollars) = (RCVM + RCVA) (Equation A5.4-4)

  1. Total recycled content value for the project (by percentage). This is expressed as a percentage of the total material cost and shall be determined by Equations A5.4-4 and A5.4-5. The result of this calculation may be directly compared for compliance with Tier 1 (10 percent) or Tier 2 (15 percent) prerequisites.

Total Recycled Content Value (percent) =

[Total Recycled Content Value (dollars) ÷ Total Material Cost (dollars)] × 100

(Equation A5.4-5)

A5.405.4.3 Determination of recycled content value of materials (RCVM). The recycled content value of each material (RCVM) is calculated by multiplying the cost of material, as defined by the recycled content. See Equations A5.4-6 and A5.4-7.

RCVM (dollars) = Material cost (dollars) × RCM (percent) (Equation A5.4-6)

RCM (percent) = Postconsumer content percentage + ( 1 /2) Preconsumer content percentage (Equation A5.4-7)

Notes:

  1. If the postconsumer and preconsumer recycled content is provided in pounds, Equation A5.4-7 may be used, but the final result (in pounds) must be multiplied by 100 to show RCM as a percentage.

  2. If the manufacturer does not separately identify the pre-consumer and post-consumer recycled content of a material but reports it as a total single percentage, the total amount shall be considered preconsumer recycled material.

A5.405.4.4 Determination of recycled content value of assemblies – (RCVA). Recycled content value of assemblies is calculated by multiplying the total cost of assembly by the total recycled content of the assembly (RCA), and shall be determined by Equation A5.4-8.

RCVA (dollars) = Assembly cost (dollars) × Total RCA (percent) (Equation A5.4-8)

If not provided by the manufacturer, Total RCA (percent) is the sum (Σ) of the Proportional Recycled Content (PRCM) of each material in the assembly. RCA shall be determined by Equation A4.4-9.

RCA = Σ PRCM (Equation A5.4-9)

PRCM of each material may be calculated by one of two methods using the following formulas:

Method 1: Recycled content (Postconsumer and Preconsumer) of each material provided in percentages

PRCM (percent) = Weight of material (percent) × RCM (percent) (Equation A5.4-10)

Weight of material (percent) =

[Weight of material (lbs) ÷ Weight of assembly (lbs)] × 100 (Equation A5.4-11)

NONRESIDENTIAL VOLUNTARY MEASURES

RCM (percent) = Postconsumer content percentage + ( 1 /2) Preconsumer content percentage (See Equation A5.4-7)

Method 2: Recycled content (Postconsumer and Preconsumer) provided in pounds

PRCM (percent) = [RCM (lbs) Weight of material (lbs)] × 100 (Equation A5.4-12)

RCM (lbs) = Postconsumer content (lbs) + ( 1 /2) Preconsumer content (lbs) (Equation A5.4-13)

Note: If the manufacturer does not separately identify the pre-consumer and post-consumer recycled content of a material but reports it as a total single percentage, the total amount shall be considered preconsumer recycled material.

A5.405.4.5 Alternate method for concrete. When Supplementary Cementitious Materials (SCMs), such as fly ash or ground blast furnace slag cement, are used in concrete, an alternate method of calculating and reporting recycled content in concrete products shall be permitted. When determining the recycled content value, the percent recycled content shall be multiplied by the cost of the cementitious materials only, not the total cost of the concrete.

TABLE A5.405.4 MINIMUM RECYCLED CONTENT LEVELS

MATERIAL/
PRODUCT TYPE
MINIMUM
TOTAL RECYCLED
CONTENT
MINIMUM
POST-CONSUMER
RECYCLED
CONTENT
Insulation, fiberglass 30% 30%
Insulation, cellulose 75% 75%
Exterior Paint, latex 50% 50%
Carpet, nylon 10% 10%
Compost 80% 80%
Mulch 80% 80%
Acoustical ceiling panels 60%
Drywall, gypsum 4% 4%
Aggregate base 80% 80%

A5.405.5 Cement and concrete. Use cement and concrete made with recycled products and complying with the following sections.

A5.405.5.1 Cement. Cement shall comply with one of the following standards:

  1. Portland cement shall meet ASTM C150, Standard Specification for Portland Cement.

  2. Blended cement shall meet ASTM C595, Standard Specification for Blended Hydraulic Cement or ASTM C1157, Standard Performance Specification for Hydraulic Cement.

  3. Other Hydraulic Cements shall meet ASTM C1157, Standard Performance Specification for Hydraulic Cement.

Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.

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NONRESIDENTIAL VOLUNTARY MEASURES

A5.405.5.2 Concrete. Unless otherwise directed by the Engineer of Record, use concrete manufactured with cementitious materials in accordance with Sections A5.405.5.2.1 and A5.405.5.2.1.1, as approved by the enforcing agency.

A5.405.5.2.1 Supplementary cementitious materials (SCM). Use concrete made with one or more supplementary cementitious materials (SCM) conforming to the following standards:

  1. Fly ash conforming to ASTM C618, Specifica- tion for Coal Fly Ash and Raw or Calcined Natu- ral Pozzolan for Use in Concrete.

  2. Slag cement (GGBFS) conforming to ASTM C989, Specification for Use in Concrete and Mortars.

  3. Silica fume conforming to ASTM C1240, Speci- fication for Silica Fume Used in Cementitious Mixtures.

  4. Natural pozzolan conforming to ASTM C618, Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete.

  5. Blended supplementary cementitious materials conforming to ASTM C1697, Standard Specification for Blended Supplementary Cementitious Materials. The amount of each SCM in the blend will be used separately in calculating Equation A5.4-1. If Class C fly ash is used in the blend, it will be considered to be “SL” for the purposes of satisfying the equation.

  6. Ultra-fine fly ash (UFFA) conforming to ASTM C618, Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete and the following chemical and physical require

  7. Metakaolin conforming to ASTM C618, Specifi- cation for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete, the fol- lowing chemical and physical requirements:

Chemical Requirements Percent
Silicon Dioxide (SiO2) + Aluminum
Oxide (Al2O3)
92.0 min.
Calcium Oxide (CaO) 1.0 max.
Sulfur Trioxide (SO3) 1.0 max.
Loss on ignition 1.2 max.
Available Alkalies (as Na2O) equivalent 1.0 max.
Physical Requirements Percent
Particle size distribution
Less than 45 microns
95
Strength Activity Index with portland
cement
7 days
28 days
100 (minimum
% of control)
100 (minimum
% of control)

ments:

Chemical Requirements Percent
Sulfur Trioxide (SO3) 1.5 max.
Loss on ignition 1.2 max.
Available Alkalies (as Na2O) equivalent 1.5 max.
Physical Requirements Percent
Particle size distribution
Less than 3.5 microns
Less than 9.0 microns
50
90
Strength Activity Index with portland
cement
7 days
28 days
95 (minimum
% of control)
110 (minimum
% of control)
Expansion at 16 days when testing job
materials in conformance with
ASTM C1567*
0.10 max.
  • In the test mix, cement shall be replaced with at least 12% UFFA by weight.
  1. Other materials with comparable or superior environmental benefits, as approved by the Engineer of Record and enforcing authority.

A5.405.5.2.1.1 Mix design equation. Use any combination of one or more SCM, satisfying Equation A5.4-14. When ASTM C595 or ASTM C1157 cement is used, the amount of SCM in these cements shall be used in calculating Equation A5.4-14.

Exception: Minimums in mix designs approved by the Engineer of Record may be lower where high early strength is needed for concrete products or to meet an accelerated project schedule.

F/ 25 + SL/ 50 + UF /12 ≥1 (Equation A5.4-14)

where:

F = Fly ash, natural pozzolan or other approved

SCM as a percent of total cementitious material for concrete on the project.

SL = GGBFS, as a percent of total cementitious

material for concrete on the project.

UF = Silica fume, metakaolin or UFFA, as a percent

of total cementitious material for concrete on the project.

A5.405.5.3 Additional means of compliance. Any of the following measures shall be permitted to be employed for the production of cement or concrete, depending on their availability and suitability, in conjunction with Section A5.405.5.2.

A5.405.5.3.1 Cement. The following measures shall be permitted to be used in the manufacture of cement.

A5.405.5.3.1.1 Alternative fuels. The use of alternative fuels where permitted by state or local air quality standards.

144 2019 CALIFORNIA GREEN BUILDING STANDARDS CODE

Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.

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A5.405.5.3.1.2 Alternative power. Alternate electric power generated at the cement plant and/or green power purchased from the utility meeting the requirements of Section A5.211.

A5.405.5.3.2 Concrete. The following measures shall be permitted to be used in the manufacture of concrete.

A5.405.5.3.2.1 Alternative energy. Renewable or alternative energy meeting the requirements of Section A5.211.

A5.405.5.3.2.2 Recycled aggregates. Concrete made with one or more of the following materials:

  1. Blast furnace slag as a lightweight aggregate in unreinforced concrete.

  2. Recycled concrete that meets grading requirements of ASTM C33, Standard Specification for Concrete Aggregates.

  3. Other materials with comparable or superior environmental benefits, as approved by the engineer and enforcing authority.

A5.405.5.3.2.3 Mixing water. Water recycled by the local water purveyor or water reclaimed from manufacturing processes and conforming to ASTM C1602, Standard Specification for Mixing Water Used in the Production of Hydraulic Cement Concrete.

A5.405.5.3.2.4 High strength concrete. Concrete elements designed to reduce their total size compared to standard 3,000 psi concrete, thereby reducing the total volume of cement, aggregate and water used on the project, as approved by the Engineer of Record.

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