Title 24 · California Energy Code

Requirements for field‑fabricated, site‑built and field‑installed fenestration

Field‑fabricated windows/doors are permitted only if compliance paperwork shows the installation meets the code’s default U‑factors and SHGC (or NFRC ratings), the units are caulked and weatherstripped (with a few exceptions), and site‑built fenestration in nonresidential buildings has NA7 acceptance and a Certificate of Acceptance filed before occupancy.

Last reviewed: July 6, 2026

What the code requires — plain English

Field‑fabricated fenestration and field‑fabricated exterior doors may only be installed when the project’s compliance documentation demonstrates the installation meets the code using the applicable U‑factors and SHGC values from the default tables (Table 110.6‑A / Table A6.205.1‑A and Table 110.6‑B / Table A6.205.1‑B). Field‑fabricated assemblies must be caulked to the building and weatherstripped unless exempt. Site‑built (also called site‑built fenestration) in nonresidential buildings must be certified to the Acceptance Requirements in Reference Nonresidential Appendix NA7 and a Certificate of Acceptance submitted before occupancy. See § A6.205.1.2 and § 110.6 for the controlling requirements.

The single most important rule: Field‑fabricated fenestration and exterior doors are allowed only when the compliance documentation demonstrates conformance using the code’s default U‑factors and SHGC (or NFRC ratings where applicable), and the installed unit is sealed to limit air and water movement. § A6.205.1.2 and § 110.6.

Requirements in detail

Key defined terms (first use)

  • Field‑fabricated — a fenestration product whose frame is made at the construction site from standard dimensional lumber or other materials not previously cut/form‑made for a fenestration product. Field‑fabricated does not include site‑built fenestration. § (definition).
  • Site‑built — fenestration designed to be field‑glazed or field‑assembled from factory‑cut or factory‑formed framing and glazing (examples: storefront systems, curtain walls). § (definition).

What documentation is required

  • Compliance documentation must show the installed performance values are met using either:
    • NFRC ratings where available (NFRC 100, 200, etc.), or
    • the applicable default U‑factors and SHGC values from the code tables (Table 110.6‑A / A6.205.1‑A and Table 110.6‑B / A6.205.1‑B). § 110.6(b); § A6.205.1.2.
  • Labeling: manufactured units require a temporary label (not removed before inspection) and, if NFRC‑rated, a permanent label (or label certificate for site‑built products) per Title 24 labeling rules. § A6.205.1.1.4; § 110.6(5).
  • Site‑built acceptance: Site‑built fenestration in non‑low‑rise nonresidential buildings must be certified as meeting the Acceptance Requirements in Reference Nonresidential Appendix NA7 and a Certificate of Acceptance submitted to the enforcement agency before occupancy. § A6.205.1.1.5; § 110.6(6).

Installation / field work requirements

  • Sealing: Field‑fabricated fenestration and exterior doors shall be caulked between the fenestration product and the building and shall be weatherstripped. Exception: unframed glass doors and fire doors need not be caulked or weatherstripped. § A6.205.1.2; § 110.6(b) exception.
  • Air leakage testing: Manufactured products must meet the air infiltration limits when tested to NFRC‑400 or ASTM E283—however field‑fabricated assemblies are explicitly excepted from that manufactured‑product air leakage certification requirement; they are permitted when the documentation approach using the code default values is demonstrated. § 110.6(a)1 (exception note).

Decision‑relevant table (quick reference)

Decision item Required value/threshold What to show Code reference
Source of allowable U‑factor for field‑fabricated units Use default table values in Table 110.6‑A (or Table A6.205.1‑A for CalGreen) unless NFRC rating is used Compliance documentation showing U used § A6.205.1.2 and § 110.6(b)
Source of allowable SHGC for field‑fabricated units Use Table 110.6‑B (or Table A6.205.1‑B) or NFRC 200 values Compliance documentation showing SHGC used § A6.205.1.2 and § 110.6(b)
Sealing / weatherstripping Must be caulked and weatherstripped at frame‑to‑structure interface Inspection / installation note on field drawings; verification on commissioning/inspection § A6.205.1.2; § 110.6(b)
Site‑built fenestration (nonresidential) Must satisfy Acceptance Requirements of NA7; matching label certificate for each product installed; submit Certificate of Acceptance NA7 acceptance documentation and certificate filed with enforcement agency § A6.205.1.1.5; § 110.6(6)
Air leakage allowable for manufactured products (not field‑fabricated) 0.3 cfm/ft² of window area (typical); other door limits for specific doors; tested to NFRC‑400 or ASTM E283 at 75 Pa Manufacturer certification or independent certifier § 110.6(a)1

Where to find the default performance numbers

  • Refer to Table 110.6‑A (default U‑factors) and Table 110.6‑B (default SHGC) in the Energy Code; identical tables appear as Table A6.205.1‑A and Table A6.205.1‑B in CalGreen Appendix A6 for the health‑facility voluntary provisions. The tables list values by frame material and product type (single vs double pane, skylight, doors, etc.). § 110.6; § A6.205.1.2.

Exceptions & special cases

  • Unframed glass doors and fire doors are excepted from the caulking and weatherstripping requirement. § A6.205.1.2; § 110.6(b) exception.
  • Skylight exceptions: for certain small skylight areas in buildings under the nonresidential standards, the default U‑factor and SHGC may be calculated per Reference Nonresidential Appendix NA6 instead of using the table values (examples shown as exceptions in § 110.6(a)2/a3). Check Appendix NA6 when skylight area thresholds apply (see 200 sq ft threshold language in the Energy Code text). § 110.6(a)2/a3.
  • For site‑built fenestration totals beneath certain area thresholds (CalGreen references an alternate NA6 calculation when site‑built area is less than 10,000 sq ft), see § A6.205.1.1.3 and NA6.

If you need a specific numeric U‑factor or SHGC for a particular frame/product combination, use the appropriate Table 110.6‑A/110.6‑B (or Tables labeled A6.205.1‑A/B in CalGreen). Those tables are reproduced in the code text.

Common mistakes

  • Treating field‑fabricated as equivalent to manufactured: manufactured products must carry manufacturer certification and air leakage testing; field‑fabricated rely on documented default values and field sealing—requirements differ. See the definitions and § 110.6 and § A6.205.1.2.
  • Failing to submit the Certificate of Acceptance for site‑built fenestration (NA7 acceptance) before occupancy — this will hold up permit close‑out. § A6.205.1.1.5; § 110.6(6).
  • Removing the temporary label before inspection or not providing the matching label certificate for site‑built products. Label requirements are mandatory. § A6.205.1.1.4; § 110.6(5).
  • Applying NFRC values where no NFRC rating exists (instead default table values must be used) or failing to adjust default U‑factors when the product has true divided lites or narrow spacers (the tables include adjustment notes). See Table notes to Table 110.6‑A. § 110.6 (table notes).

Worked example — concrete scenario

Scenario: A contractor installs a field‑fabricated double‑pane fixed storefront window system (nonmetal frame) at a new outpatient clinic. The owner must demonstrate compliance to the enforcement agency.

Steps (with code grounding):

  1. Identify applicable default performance values: for a nonmetal, fixed, double‑pane product the default U‑factor = 0.55 (Table 110.6‑A) and an appropriate SHGC from Table 110.6‑B (pick the glazing type row that applies). Show the tables on the compliance forms. § 110.6(b); Table 110.6‑A/B.
  2. Document installation: indicate on the construction documents and compliance paperwork that the installation will use the Table values and specify sealant and weatherstripping details at the frame‑to‑structure interface. Cite § A6.205.1.2 / § 110.6(b) showing the requirement to caulk and weatherstrip.
  3. Inspection readiness: leave temporary labels or label certificates accessible for inspection per labeling rules. If the glazing is site‑built, prepare the Certificate of Acceptance per Appendix NA7. § A6.205.1.1.4; § A6.205.1.1.5; § 110.6(5–6).
  4. At final inspection, provide the compliance documentation that shows the unit used the default U‑factor/SHGC values, indicates sealing/weatherstripping was installed, and, if site‑built, supplies the NA7 Certificate of Acceptance. Inspectors will verify labels and sealing. § A6.205.1.2; § 110.6.

Result: If documentation and field sealing are verified and NA7 acceptance (for site‑built) is provided, the field‑fabricated installation is acceptable under the cited sections.

Related provisions (quick list)

  • § A6.205.1.2 — Installation of field‑fabricated fenestration and exterior doors (CalGreen Appendix A6).
  • § A6.205.1.1.4 / A6.205.1.1.5 — Labeling and fenestration acceptance requirements for site‑built (CalGreen).
  • § 110.6 — Mandatory requirements for fenestration products and exterior doors; includes Table 110.6‑A (U‑factors), Table 110.6‑B (SHGC), labeling and NA7 acceptance reference.
  • Reference Nonresidential Appendix NA7 — Acceptance Requirements for site‑built fenestration (see § 110.6(6) and the NA7 reference).
  • Reference Nonresidential Appendix NA6 — Calculation method for default values in limited skylight/site‑built area exceptions (see exceptions in § 110.6 and § A6.205.1.1.3).

Code references

Grounded in the retrieved California Energy Code — click a citation to read the verbatim passage:

  • § 205.1.1.4 High relevance — show source text

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

    APPENDIX A6.1VOLUNTARY STANDARDS FOR HEALTH FACILITIES [OSHPD 1, 2 & 4]

    A6.205.1.1.4 Labeling. Fenestration products shall:

    1. Have a temporary label (or label certificate for site- built fenestration) meeting the requirements of Section 10111(a)1 of Title 24, Part 1 not to be removed before inspection by the enforcement agency, listing the certified U factor and SHGC and certifying that the air leakage requirements of Section A6.205.1.1.1 are met for each product line; and
    2. Have a permanent label (or label certificate for site-built fenestration) meeting the requirements of Section 10111(a)2 of Title 24, Part 1 if the product is rated using NFRC procedures.

    A6.205.1.1.5 Fenestration acceptance requirements. Before an occupancy permit is granted, site-built fenestration products in other than low-rise residential buildings shall be certified as meeting the Acceptance Requirements for Code Compliance, as specified by the Reference Nonresidential Appendix NA7 of the California Energy Commission 2008 Building Energy Efficiency Standards for Residential and Nonresidential Buildings to ensure that site-built fenestration meet Standards requirements, including a matching label certificate for each product installed and be readily accessible at the project location. A Certificate of Acceptance shall be submitted to the enforcement agency that certifies that the fenestration product meets the acceptance requirements.

    Exception: Fenestration products removed and reinstalled as part of a building alteration or addition.

    A6.205.1.2 Installation of field-fabricated fenestration and exterior doors. Field-fabricated fenestration and field-fabricated exterior doors may be installed only if the compliance documentation has demonstrated compliance for the installation using U factors from Table A6.205.1-A and SHGC values from Table A6.205.1-B. Field-fabricated fenestration and field-fabricated exterior doors shall be caulked between the fenestration products or exterior door and the building and shall be weatherstripped.

    Exception: Unframed glass doors and fire doors need not be weatherstripped or caulked.

    A6.205.2 Joints and other openings. Joints and other openings in the building envelope that are potential sources of air leakage shall be caulked, gasketed, weatherstripped or otherwise sealed to limit infiltration and exfiltration.

    A6.205.3 Insulation and roofing products.

    A6.205.3.1 Certification by manufacturers. Any insulation shall be certified by Department of Consumer Affairs, Bureau of Household Good and Services that the insulation conductive thermal performance is approved pursuant to the California Code of Regulations, Title 24, Part 12, Chapters 12-13, Article 3,“Standards for Insulating Material.”

    A6.205.3.2 Installation of urea formaldehyde foam insulation. Urea formaldehyde foam insulation may be applied or installed only if:

    1. It is installed in exterior side walls; and

    2. A four-mil-thick plastic polyethylene vapor barrier or equivalent plastic sheathing vapor barrier is installed between the urea formaldehyde foam insulation and the interior space in all applications.

  • § 205.1.2 High relevance — show source text

    A6.205.1.2 Installation of field-fabricated fenestration and exterior doors. Field-fabricated fenestration and field-fabricated exterior doors may be installed only if the compliance documentation has demonstrated compliance for the installation using U factors from Table A6.205.1-A and SHGC values from Table A6.205.1-B. Field-fabricated fenestration and field-fabricated exterior doors shall be caulked between the fenestration products or exterior door and the building and shall be weatherstripped.

    Exception: Unframed glass doors and fire doors need not be weatherstripped or caulked.

    A6.205.2 Joints and other openings. Joints and other openings in the building envelope that are potential sources of air leakage shall be caulked, gasketed, weatherstripped or otherwise sealed to limit infiltration and exfiltration.

    A6.205.3 Insulation and roofing products.

    A6.205.3.1 Certification by manufacturers. Any insulation shall be certified by Department of Consumer Affairs, Bureau of Household Good and Services that the insulation conductive thermal performance is approved pursuant to the California Code of Regulations, Title 24, Part 12, Chapters 12-13, Article 3,“Standards for Insulating Material.”

    A6.205.3.2 Installation of urea formaldehyde foam insulation. Urea formaldehyde foam insulation may be applied or installed only if:

    1. It is installed in exterior side walls; and

    2. A four-mil-thick plastic polyethylene vapor barrier or equivalent plastic sheathing vapor barrier is installed between the urea formaldehyde foam insulation and the interior space in all applications.

    A6.205.3.3 Flame spread rating. All insulating material shall be installed in compliance with the flame spread rating and smoke density requirements of the Title 24, Part 2, California Building Code.

    A6.205.3.4 Installation of insulation in existing buildings. Insulation installed in an existing attic or on an existing duct or water heater, shall comply with the applicable requirements of Subsections A6.205.3.4.1, A6.205.3.4.2 and A6.205.3.4.3 below. If a contractor installs the insulation, the contractor shall certify to the customer, in writing, that the insulation meets the applicable requirements of Subsections A6.205.3.4.1, A6.205.3.4.2 and A6.205.3.4.3 below.

    A6.205.3.4.1 Attics. If insulation is installed in the existing attic of a low-rise residential building, the R-value of the total amount of insulation (after addition of insulation to the amount, if any, already in the attic) shall be at least R-38 in climate zones 1 and 16; and R-30 in all other climate zones.

    Exception: Where the accessible space in the attic is not large enough to accommodate the required R-value, the entire accessible space shall be filled with insulation provided such installation does not violate Section 1203.2 of Title 24, Part 2, California Building Code.

  • § 204.4.6 High relevance — show source text

    A6.204.4.6 Commissioning report. The CxA shall create a complete report of commissioning process activities undertaken through the design, construction and postconstruction phases of the building project and provided to the owner.

    A6.204.6 Building orientation and shading. Locate orient and shade the building as required in Section A6.106.9.

    SECTION A6.205 [OSHPD 1 & 4]—BUILDING ENVELOPE

    A6.205.1 Fenestration products and exterior doors.

    A6.205.1.1 Certification of fenestration products and exterior doors other than field-fabricated. Any fenestration product and exterior door, other than field-fabricated fenestration products and field-fabricated exterior doors, may be installed only if the manufacturer has certified to the California Energy Commission or if an independent certifying organization approved by the Commission has certified that the product complies with all of the applicable requirements of this subsection.

    A6.205.1.1.1 Air leakage. Manufactured fenestration products and exterior doors shall have air infiltration rates not exceeding 0.3 cfm/ft [2] of window area, 0.3 cfm/ft [2] of door area for residential doors, 0.3 cfm/ft [2] of door area for nonresidential single doors

    APPENDIX A6.1-4 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE

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

    APPENDIX A6.1VOLUNTARY STANDARDS FOR HEALTH FACILITIES [OSHPD 1, 2 & 4]

    (swinging and sliding) and 1.0 cfm/ft [2] for nonresidential double doors (swinging), when tested according to NFRC-400 or ASTM E283 at a pressure differential of 75 pascals (or 1.57 pounds/ft [2] ), incorporated herein by reference.

    A6.205.1.1.2 U -factor. A fenestration product’s U -factor shall be rated in accordance with NFRC 100 or the applicable default U -factor set forth in Table A.5.205.1-A.

    Exception: If the fenestration product is a skylight or is site-built fenestration in a building covered by the nonresidential standards with less than 10,000 square feet of site-built fenestration, the default U- factor may be calculated as set forth in Reference Nonresidential Appendix NA6 of the California Energy Commission 2008 Building Energy Efficiency Standards for Residential and Nonresidential Buildings.

    TABLE A.5.205.1-A—DEFAULT FENESTRATION PRODUCT U-FACTORS Col2 Col3 Col4 Col5
    FRAME PRODUCT TYPE SINGLE PANE
    U-FACTOR
    DOUBLE PANE1
    U-FACTOR
    GLASS BLOCK2
    U-FACTOR
    Metal Operable 1.28 0.79 0.87
    Metal Fixed 1.19 0.71 0.72
    Metal Greenhouse/garden window 2.26 1.40 N.A.
    Metal Doors 1.25 0.77 N.
  • § 110.6 High relevance — show source text

    (b) Installation of field-fabricated fenestration and exterior doors. Field-fabricated fenestration and field-fabricated exterior doors may be installed only if the compliance documentation has demonstrated compliance for the installation using U factors from Table 110.6-A and SHGC values from Table 110.6-B. Field-fabricated fenestration and field-fabricated exterior doors shall be caulked between the fenestration products or exterior door and the building, and shall be weatherstripped.

    Exception to Section 110.6(b): Unframed glass doors and fire doors need not be weatherstripped or caulked.

    TABLE 110.6-A—DEFAULT FENESTRATION PRODUCT U-FACTORS Col2 Col3 Col4 Col5
    FRAME1,2 PRODUCT TYPE SINGLE PANE3, 4
    U-FACTOR
    DOUBLE PANE1, 3, 4
    U-FACTOR
    GLASS BLOCK2, 3
    U-FACTOR
    Metal Operable 1.28 0.79 0.87
    Metal Fixed 1.19 0.71 0.72
    Metal Greenhouse/garden window 2.26 1.40 NA
    Metal Glazed doors 1.25 0.77 NA
    Metal Skylight 1.98 1.3 NA
    Metal, thermal break Operable NA 0.66 NA
    Metal, thermal break Fixed NA 0.55 NA
    Metal, thermal break Greenhouse/garden window NA 1.12 NA
    Metal, thermal break Glazed doors NA 0.59 NA
    Metal, thermal break Skylight NA 1.11 NA
    Nonmetal Operable 0.99 0.58 0.60
    Nonmetal Fixed 1.04 0.55 0.57
    Nonmetal Greenhouse/garden window 0.99 0.53 NA
    Nonmetal Glazed doors 1.94 1.06 NA
    Nonmetal Skylight 1.47 0.84 NA
    1. For all dual-glazed fenestration products, adjust the listed_U_-factors as follows:
    a. Add 0.05 for products with dividers between panes if spacer is less than7/16 inch wide.
    b. Add 0.05 to any product with true divided lite (dividers through the panes).
    2. Translucent or transparent panels shall use glass block values when not rated by NFRC 100.
    3. Visible Transmittance (VT) shall be calculated by using Reference Nonresidential Appendix NA6.
    4. Windows with window film applied that is not rated by NFRC 100 shall use the default values from this table.
    1. For all dual-glazed fenestration products, adjust the listed_U_-factors as follows:
    a. Add 0.05 for products with dividers between panes if spacer is less than7/16 inch wide.
    b. Add 0.05 to any product with true divided lite (dividers through the panes).
    2. Translucent or transparent panels shall use glass block values when not rated by NFRC 100.
    3.
  • § 110.6 High relevance — show source text

    Exception 2 to Section 110.6(a)4: If the fenestration product is an alteration consisting of any area; replacement of glass in a skylight product in a building covered by the nonresidential standards, the default VT may be calculated as set forth in Reference Nonresidential Appendix NA6. 5. Labeling. Fenestration products and exterior doors shall: A. Have a temporary label for manufactured fenestration products and exterior doors or a label certificate when the component modeling approach (CMA) is used and for site-built fenestration meeting the requirements of Section 10-111(a)1. The temporary label shall not be removed before inspection by the enforcement agency; and B. Have a permanent label or label certificate when the component modeling approach (CMA) is used and for sitebuilt fenestration meeting the requirements of Section 10-111(a)2 if the product is rated using NFRC procedures. 6. Fenestration acceptance requirements. Before an occupancy permit is granted site-built fenestration products in other than single-family buildings shall be certified as meeting the Acceptance Requirements for Code Compliance, as specified in the Reference Nonresidential Appendix NA7 to ensure that site-built fenestration meets Standards requirements, including a matching label certificate for product(s) installed and be readily accessible at the project location. A certificate of accep

    2025 CALIFORNIA ENERGY CODE 55

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

    ALL OCCUPANCIES—MANDATORY REQUIREMENTS FOR THE MANUFACTURE, CONSTRUCTION AND INSTALLATION OF SYSTEMS, EQUIPMENT AND BUILDING COMPONENTS

    tance certifying that the fenestration product meets the acceptance requirements shall be completed, signed and submitted to the enforcement agency. Exception to Section 110.6(a): Fenestration products removed and reinstalled as part of a building alteration or addition.

    (b) Installation of field-fabricated fenestration and exterior doors. Field-fabricated fenestration and field-fabricated exterior doors may be installed only if the compliance documentation has demonstrated compliance for the installation using U factors from Table 110.6-A and SHGC values from Table 110.6-B. Field-fabricated fenestration and field-fabricated exterior doors shall be caulked between the fenestration products or exterior door and the building, and shall be weatherstripped.

    Exception to Section 110.6(b): Unframed glass doors and fire doors need not be weatherstripped or caulked.

    TABLE 110.6-A—DEFAULT FENESTRATION PRODUCT U-FACTORS Col2 Col3 Col4 Col5
    FRAME1,2 PRODUCT TYPE SINGLE PANE3, 4
    U-FACTOR
    DOUBLE PANE1, 3, 4
    U-FACTOR
    GLASS BLOCK2, 3
    U-FACTOR
    Metal Operable 1.28 0.79 0.87
    Metal Fixed 1.19 0.71 0.72
    Metal Greenhouse/garden window 2.26 1.40 NA
    Metal Glazed doors 1.25 0.77 NA
    Metal Skylight 1.98 1.3 NA
    Metal, thermal break Operable NA 0.66 NA
    Metal,
  • § 10-111 High relevance — show source text

    HORIZONTAL SLATS, when referring to a daylighting device, is a set of adjacent surfaces located directly adjacent to vertical fenestration, oriented horizontally and projecting horizontally from its interior or exterior vertical surface.

    INTEGRATED SHADING SYSTEM is a class of fenestration products including an active layer: e.g., shades, louvers, blinds or other materials permanently integrated between two or more glazing layers. The U -factor and/or SHGC and VT of the insulating glass assembly can be altered by reversibly changing the enclosed active layer.

    LIGHT SHELF is an adjacent, opaque surfaced daylighting device located at the sill of clerestory glazing, oriented horizontally and projecting horizontally from an interior or exterior vertical surface.

    MANUFACTURED or KNOCKED DOWN PRODUCT is a fenestration product constructed of materials that are factory cut or otherwise factory formed with the specific intention of being used to fabricate a fenestration product. Knocked down or partially assembled products may be sold as a fenestration product when provided with temporary and permanent labels as described in Section 10-111, or as a site-built fenestration product when not provided with temporary and permanent labels as described in Section 10-111.

    NFRC 100 is the National Fenestration Rating Council document titled “Procedure for Determining Fenestration Product U factors,” (2020) (ANSI/NFRC 100-2020).

    NFRC 200 is the National Fenestration Rating Council document titled “Procedure for Determining Fenestration Product Solar Heat Gain Coefficients and Visible Transmittance at Normal Incidence,” (2020) (ANSI/NFRC 200-2020).

    NFRC 202 is the National Fenestration Rating Council document titled “Procedures for Determining Translucent Fenestration Product Visible Transmittance at Normal Incidence,” (2020) (ANSI/NFRC 202-2020).

    NFRC 203 is the National Fenestration Rating Council document titled “Procedure for Determining Visible Transmittance of Tubular Daylighting Devices,” (2020) (ANSI/NFRC 203-2020).

    16 2025 CALIFORNIA ENERGY CODE

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

    ALL OCCUPANCIES—GENERAL PROVISIONS

    NFRC 400 is the National Fenestration Rating Council document titled “Procedure for Determining Fenestration Product Air Leakage,” (2020) (ANSI/NFRC 400-2020).

    OPERABLE SHADING DEVICE is a device at the interior or exterior of a building or integral with a fenestration product, which is capable of being operated, either manually or automatically, to adjust the amount of solar radiation admitted to the interior of the building.

    RELATIVE SOLAR HEAT GAIN COEFFICIENT (RSHGC) is the ratio of solar heat gain through a fenestration product (corrected for external shading) to the incident solar radiation. Solar heat gain includes directly transmitted solar heat and absorbed solar radiation, which is then reradiated, conducted or convected into the space.

    SITE-BUILT is fenestration designed to be field-glazed or field assembled units using specific factory cut or otherwise factory formed framing and glazing units that are manufactured with the intention of being assembled at the construction site. These include storefront systems, curtain walls and atrium roof systems.

    SKYLIGHT ROOF RATIO (SRR) is the ratio of the skylight area to the gross exterior roof area.

  • § 10-111 High relevance — show source text

    FENESTRATION AREA is the rough opening area of any fenestration product.

    FENESTRATION PRODUCT is any transparent or translucent material plus any sash, frame, mullions and dividers, in the facade of a building, including, but not limited to, windows, glazed doors, skylights, curtain walls, dynamic glazing, garden windows, glass block and glazing used in greenhouses.

    FENESTRATION REPAIR is the reconstruction or renewal for the purpose of maintenance of any fenestration product, component or system and shall not increase the preexisting energy consumption of the repaired fenestration product, component, system or equipment. Replacement of any component, system or equipment for which there are requirements in the Standards are considered an alteration (see Fenestration, alteration) and not a repair and is subject to the requirements of Part 6 of the Standards.

    FIELD-FABRICATED is a fenestration product whose frame is made at the construction site of standard dimensional lumber or other materials that were not previously cut, or otherwise formed with the specific intention of being used to fabricate a fenestration product. Field fabricated does not include site-built fenestration.

    FIN is an opaque surface, oriented vertically and projecting outward horizontally from an exterior vertical surface.

    FIN OFFSET is the horizontal distance from the edge of exposed exterior glazing at the jamb of a window to the fin.

    FIN PROJECTION is the horizontal distance, measured outward horizontally, from the surface of exposed exterior glazing at the jamb of a window to the outward edge of a fin.

    FIXED is fenestration that is not designed to be opened or closed.

    GREENHOUSE or GARDEN WINDOW is a window unit that consists of a three-dimensional, five-sided structure generally protruding from the wall in which it is installed. Operating sash may or may not be included.

    HORIZONTAL SLATS, when referring to a daylighting device, is a set of adjacent surfaces located directly adjacent to vertical fenestration, oriented horizontally and projecting horizontally from its interior or exterior vertical surface.

    INTEGRATED SHADING SYSTEM is a class of fenestration products including an active layer: e.g., shades, louvers, blinds or other materials permanently integrated between two or more glazing layers. The U -factor and/or SHGC and VT of the insulating glass assembly can be altered by reversibly changing the enclosed active layer.

    LIGHT SHELF is an adjacent, opaque surfaced daylighting device located at the sill of clerestory glazing, oriented horizontally and projecting horizontally from an interior or exterior vertical surface.

    MANUFACTURED or KNOCKED DOWN PRODUCT is a fenestration product constructed of materials that are factory cut or otherwise factory formed with the specific intention of being used to fabricate a fenestration product. Knocked down or partially assembled products may be sold as a fenestration product when provided with temporary and permanent labels as described in Section 10-111, or as a site-built fenestration product when not provided with temporary and permanent labels as described in Section 10-111.

    NFRC 100 is the National Fenestration Rating Council document titled “Procedure for Determining Fenestration Product U factors,” (2020) (ANSI/NFRC 100-2020).

    NFRC 200 is the National Fenestration Rating Council document titled “Procedure for Determining Fenestration Product Solar Heat Gain Coefficients and Visible Transmittance at Normal Incidence,” (2020) (ANSI/NFRC 200-2020).

  • California Energy Code High relevance — show source text

    CMAST (component modeling approach software tool) is an NFRC approved software that allows a user to create a fenestration product “virtually” and generate its energy-related performance ratings, including the thermal performance U -factor, solar heat gain coefficient, and visible transmittance.

    CURTAIN WALL/STOREFRONT is an external non-bearing wall intended to separate the exterior nonconditioned and interior conditioned spaces. It also consists of any combination of framing materials, fixed glazing, opaque glazing, operable windows or other in-fill materials.

    Note: Window wall is also included as part of the curtain wall/storefront fenestration category.

    DUAL-GLAZED GREENHOUSE WINDOWS is a double glass pane separated by an air or other gas space that adds conditioned volume but not conditioned floor area to a building.

    DYNAMIC GLAZING SYSTEMS are glazing systems that have the ability to reversibly change their performance properties, including U -factor, Solar Heat Gain Coefficient (SHGC) and/or Visible Transmittance (VT) between well-defined end points. These may include, but are not limited to, chromogenic glazing systems and integrated shading systems (defined below). Dynamic Glazing systems do not include internally mounted or externally mounted shading devices that attach to the window framing/glazing that may or may not be removable.

    FENESTRATION ALTERATION is any change to an existing building’s exterior fenestration product that is not a repair (see “fenestration repair”) that: i. Replaces existing fenestration in an existing wall or roof with no net area added; or ii. Replaces existing fenestration and adds new net area in the existing wall or roof; or iii. Adds a new window that increases the net fenestration area to an existing wall or roof.

    FENESTRATION AREA is the rough opening area of any fenestration product.

    FENESTRATION PRODUCT is any transparent or translucent material plus any sash, frame, mullions and dividers, in the facade of a building, including, but not limited to, windows, glazed doors, skylights, curtain walls, dynamic glazing, garden windows, glass block and glazing used in greenhouses.

    FENESTRATION REPAIR is the reconstruction or renewal for the purpose of maintenance of any fenestration product, component or system and shall not increase the preexisting energy consumption of the repaired fenestration product, component, system or equipment. Replacement of any component, system or equipment for which there are requirements in the Standards are considered an alteration (see Fenestration, alteration) and not a repair and is subject to the requirements of Part 6 of the Standards.

    FIELD-FABRICATED is a fenestration product whose frame is made at the construction site of standard dimensional lumber or other materials that were not previously cut, or otherwise formed with the specific intention of being used to fabricate a fenestration product. Field fabricated does not include site-built fenestration.

    FIN is an opaque surface, oriented vertically and projecting outward horizontally from an exterior vertical surface.

    FIN OFFSET is the horizontal distance from the edge of exposed exterior glazing at the jamb of a window to the fin.

    FIN PROJECTION is the horizontal distance, measured outward horizontally, from the surface of exposed exterior glazing at the jamb of a window to the outward edge of a fin.

    FIXED is fenestration that is not designed to be opened or closed.

  • § 106.11. High relevance — show source text

    **Locate orient and shade the building as
    required in Section A6.106.11.||||| |SECTION A6.205 Building Envelope||||| |A6.205.1 Fenestration products and exterior doors.
    A6.205.1.1 Certification of fenestration products and exterior door other than field-
    fabricated.||||| |A6.205.1.2 Installation of field-fabricated fenestration and exterior doors.||||| |A6.205.2 Joints and other openings.||||| |A6.205.3 Installation and roofing products.|||||

    2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A6.1-37

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

    APPENDIX A6.1VOLUNTARY STANDARDS FOR HEALTH FACILITIES [OSHPD 1, 2 & 4]

    NONRESIDENTIAL OCCUPANCIES APPLICATION CHECKLIST [OSHPD 1, 2 and 4] continued

    FEATURE OR MEASURE COMPLIANCE LEVELS Col3 Col4 NOTES
    FEATURE OR MEASURE Mandatory
    CALGreen
    VOLUNTARY
    CALGreen
    VOLUNTARY
    CALGreen
    VOLUNTARY
    CALGreen
    FEATURE OR MEASURE Mandatory
    CALGreen
    Tier 1 Tier 2 Tier 2
    SECTION A6.207 HVAC Design, Equipment and Installation
    A6.207.1 Space-conditioning equipment certification by manufacturers.
    A6.207.1.1 Efficiency.
    A6.207.1.2 Controls for heat pumps with supplementary electric resistance heaters.
    A6.207.1.3 Thermostats.
    A6.207.1.4 Gas-and oil-fired furnace standby loss controls.








    A6.207.2 Space conditioning systems.
    A6.207.2.1 Supply air temperature reset controls.
    A6.207.2.2 Electric resistance heating.
    A6.207.2.3 Heat rejection systems.
    A6.207.2.4 Hydronic system measures.
    A6.207.2.5 Air distribution system duct leakage sealing.
    **A6.207.2.6 Variable air volume control for single zone systems.
  • § 204.4.3. High relevance — show source text

    **A commissioning plan describing how the project will be
    commissioned shall be started during the design phase of the building project and shall
    include as a minimum items listed in Section A6.204.4.3.
    A6.204.4.4 Functional performance testingshall demonstrate the correct installation and
    operation of each component, system and system-to-system interface in accordance with
    the approved plans and specifications.
    **A6.204.4.5 Post construction documentation and training.**A systems manual and
    systems operations training are required.
    **A6.204.4.5.1 Systems manual.**The systems manual shall be delivered to the building
    owner and facilities operator and shall include the items listed in Section A6.204.4.5.1.
    A6.204.4.5.2 Systems operations training. The training of the appropriate maintenance
    staff for each equipment type and/or system shall include as a minimum items listed in
    Section A6.204.4.5.2.
    **A6.204.4.6 Commissioning report.**A complete report of commissioning process activities
    undertaken through the design, construction and postconstruction phases of the building
    project shall be completed and provided to the owner.||







    |







    || |**A6.204.6 Building orientation and shading.**Locate orient and shade the building as
    required in Section A6.106.11.||||| |SECTION A6.205 Building Envelope||||| |A6.205.1 Fenestration products and exterior doors.
    A6.205.1.1 Certification of fenestration products and exterior door other than field-
    fabricated.||||| |A6.205.1.2 Installation of field-fabricated fenestration and exterior doors.||||| |A6.205.2 Joints and other openings.||||| |A6.205.3 Installation and roofing products.|||||

    2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A6.1-37

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

    APPENDIX A6.1VOLUNTARY STANDARDS FOR HEALTH FACILITIES [OSHPD 1, 2 & 4]

    NONRESIDENTIAL OCCUPANCIES APPLICATION CHECKLIST [OSHPD 1, 2 and 4] continued

  • § 0.69 High relevance — show source text

    A.| |Metal, thermal break|Fixed|Clear|N.A.|0.69|N.A.| |Metal, thermal break|Operable|Tinted|N.A.|0.53|N.A.| |Metal, thermal break|Fixed|Tinted|N.A.|0.57|N.A.| |Nonmetal|Operable|Clear|0.74|0.65|0.70| |Nonmetal|Fixed|Clear|0.76|0.67|0.67| |Nonmetal|Operable|Tinted|0.60|0.53|N.A.| |Nonmetal|Fixed|Tinted|0.63|0.55|N.A.| |N.A. = Not applicable.
    1. Translucent or transparent panels shall use glass block values.|N.A. = Not applicable.
    1. Translucent or transparent panels shall use glass block values.|N.A. = Not applicable.
    1. Translucent or transparent panels shall use glass block values.|N.A. = Not applicable.
    1. Translucent or transparent panels shall use glass block values.|N.A. = Not applicable.
    1. Translucent or transparent panels shall use glass block values.|N.A. = Not applicable.
    1. Translucent or transparent panels shall use glass block values.|

    2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A6.1-5

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

    APPENDIX A6.1VOLUNTARY STANDARDS FOR HEALTH FACILITIES [OSHPD 1, 2 & 4]

    A6.205.1.1.4 Labeling. Fenestration products shall:

    1. Have a temporary label (or label certificate for site- built fenestration) meeting the requirements of Section 10111(a)1 of Title 24, Part 1 not to be removed before inspection by the enforcement agency, listing the certified U factor and SHGC and certifying that the air leakage requirements of Section A6.205.1.1.1 are met for each product line; and
    2. Have a permanent label (or label certificate for site-built fenestration) meeting the requirements of Section 10111(a)2 of Title 24, Part 1 if the product is rated using NFRC procedures.

    A6.205.1.1.5 Fenestration acceptance requirements. Before an occupancy permit is granted, site-built fenestration products in other than low-rise residential buildings shall be certified as meeting the Acceptance Requirements for Code Compliance, as specified by the Reference Nonresidential Appendix NA7 of the California Energy Commission 2008 Building Energy Efficiency Standards for Residential and Nonresidential Buildings to ensure that site-built fenestration meet Standards requirements, including a matching label certificate for each product installed and be readily accessible at the project location. A Certificate of Acceptance shall be submitted to the enforcement agency that certifies that the fenestration product meets the acceptance requirements.

    Exception: Fenestration products removed and reinstalled as part of a building alteration or addition.

  • § 0.3 High relevance — show source text
    1. Air leakage. Manufactured fenestration products and exterior doors shall have air infiltration rates not exceeding 0.3 cfm/ft [2] of window area, 0.3 cfm/ft [2] of door area for residential doors, 0.3 cfm/ft [2] of door area for nonresidential single doors (swinging and sliding), and 1.0 cfm/ft [2] for nonresidential double doors (swinging), when tested according to NFRC400 or ASTM E283 at a pressure differential of 75 pascals (or 1.57 pounds/ft [2] ), incorporated herein by reference.

    NOTES TO SECTION 110.6(a)1: Pet doors must meet 0.3 cfm/ft [2] when tested according to ASTM E283 at 75 pascals (or 1.57 pounds per square foot).

    AAMA/WDMA/CSA 101/I.S.2/A440-2011 specification is equivalent to ASTM E283 at a pressure differential of 75 pascals (or 1.57 pounds per square foot) and satisfies the air leakage certification requirements of this section.

    Exception to Section 110.6(a)1: Field-fabricated fenestration and field-fabricated exterior doors.

    1. U -factor. The fenestration product and exterior door’s U -factor shall be rated in accordance with NFRC 100, or use the applicable default U -factor set forth in Table 110.6-A.

    Exception 1 to Section 110.6(a)2: If the fenestration product is a skylight in a building covered by the nonresidential standards with less than 200 square feet of skylight area, the default U -factor may be calculated as set forth in Reference Nonresidential Appendix NA6.

    Exception 2 to Section 110.6(a)2: If the fenestration product is an alteration consisting of any area replacement of glass in a skylight product in a building covered by the nonresidential standards, the default U -factor may be calculated as set forth in Reference Nonresidential Appendix NA6. 3. Solar heat gain coefficient SHGC. The fenestration product’s SHGC shall be rated in accordance with NFRC 200, or use the applicable default SHGC set forth in Table 110.6-B.

    Exception 1 to Section 110.6(a)3: If the fenestration product is a skylight in a building covered by the nonresidential standards with less than 200 square feet of skylight area, the default SHGC may be calculated as set forth in Reference Nonresidential Appendix NA6.

    Exception 2 to Section 110.6(a)3: If the fenestration product is an alteration consisting of any area replacement of glass in a skylight product in a building covered by the nonresidential standards, the default SHGC may be calculated as set forth in Reference Nonresidential Appendix NA6. 4. Visible transmittance (VT). The fenestration product’s VT shall be rated in accordance with NFRC 200 or ASTM E972. For tubular daylighting devices VT shall be rated using NFRC 203.

Frequently asked questions

Who decides whether a fenestration product is “field‑fabricated” or “site‑built”?

The code definition determines the classification: field‑fabricated is framed on site from non‑preformed pieces; site‑built is assembled on site from factory‑cut/formed components (e.g., curtain walls, storefronts). See the keyword definitions in the Energy Code.

Do field‑fabricated windows need NFRC ratings?

No. Field‑fabricated assemblies are accepted when compliance documentation demonstrates conformity using the code’s default U‑factor and SHGC tables (or NFRC values if provided). Use the default tables when NFRC ratings are unavailable. § A6.205.1.2; § 110.6.

Is weatherstripping always required?

Yes for field‑fabricated fenestration and exterior doors, except for unframed glass doors and fire doors, which are exempt from the caulking/weatherstripping requirement. § A6.205.1.2; § 110.6(b) exception.

What paperwork must be on site for site‑built fenestration?

A matching label certificate for each installed product and a completed Certificate of Acceptance showing conformance with Reference Appendix NA7 must be readily accessible and submitted to the enforcement agency prior to occupancy. § A6.205.1.1.5; § 110.6(6).

If I apply window film in the field, can I use NFRC values?

If window film is not rated by NFRC, the code directs use of default table values for windows with applied film (see Table notes). Check Table 110.6‑A/B notes for the specific guidance.

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