CHBC · California Historical Building Code
When can historic glazing and original doors be accepted in fire‑rated assemblies?
Under the California Historical Building Code **§ 8-402.3**, historic glass and original solid wood doors can be retained in interior walls required to be one‑hour fire rated only if the openings are operable and fitted with proper smoke seals and the space is protected by an automatic sprinkler system; approval is by the enforcing agency.
Last reviewed: July 6, 2026
What the code requires — 2–4 sentences
The California Historical Building Code allows historical glazing materials and solid wood unrated doors to be approved in interior walls required to have a one‑hour fire rating when two conditions are met: the openings (windows/doors) are operable and fitted with appropriate smoke seals, and the affected area is protected by an automatic sprinkler system. The controlling provision is § 8-402.3, which explicitly ties acceptance of historic glazing/doors to those two requirements and to the presence of sprinklers.
The single most important rule: historic glass and original solid‑wood doors can stay in one‑hour interior fire walls only if the openings have proper smoke‑sealing and the space is covered by an automatic sprinkler system.
Requirements in detail
Scope (what assemblies this applies to)
- Applies to interior walls required to have a one‑hour fire rating — the CHBC language is specific to one‑hour interior-rated walls. § 8-402.3 is the authority.
- The CHBC does not in § 8-402.3 itself expand or list acceptance for other wall ratings (e.g., 2‑hour fire barriers); where the CHBC is silent you must rely on the regular code or the enforcing agency.
Conditions to approve historic glazing or original doors
The historic glazing or original (solid wood, unrated) door may be accepted only when:
- the window or door is operable and provided with appropriate smoke seals, and
- the area affected (the room/compartment) is provided with an automatic sprinkler system. § 8-402.3 requires both elements as a package.
The CHBC elsewhere references sprinkler provisions and alternative compliance paths:
- § 8-402.1 and § 8-402.2 describe how automatic sprinklers may be used to satisfy fire‑resistance or one‑hour upgrade requirements and how sprinklers can be a basis for alternative acceptance. This supports the CHBC’s reliance on sprinklers in § 8-402.3.
Who decides and how approval is documented
- Approval is through the enforcing agency — the CHBC grants the enforcing agency discretion to approve “historical glazing materials and solid wood unrated doors” under the stated conditions. The code text indicates these items “may be approved” — i.e., subject to jurisdictional review and acceptance. § 8-402.3 (and other CHBC sections on existing/historical materials) frame that approval.
Decision‑relevant dimensions and values (quick reference)
| Decision dimension | Accept/require | Code reference |
|---|---|---|
| Assembly type | Interior wall required to have one‑hour fire rating | § 8-402.3 |
| Historic glazing allowed? | Yes — if operable and smoke‑sealed and space is sprinklered | § 8-402.3 |
| Solid wood (unrated) doors allowed? | Yes — under same conditions as glazing | § 8-402.3 |
| Automatic sprinkler system required? | Yes — area must be provided with sprinklers (see CHBC sprinkler sections) | § 8-402.3, see also § 8-402.1, § 8-402.2 |
| Smoke seals / gasketing | Appropriate smoke seals required on operable openings | § 8-402.3 |
| Applicability to higher‑rated fire barriers or exterior walls | Not authorized by § 8-402.3 — CHBC text is specific to one‑hour interior walls; consult regular code and enforcing agency | § 8-402.3 (silence on other ratings) |
Interaction with regular code fire‑rating glazing rules
- The CHBC provision is a preservation‑oriented alternative for qualified historical buildings; it does not rewrite all regular code glazing rules. For assemblies outside the CHBC scope (or for higher‑rated assemblies), the regular code limits such as fire‑protection/fire‑resistance glazing test and size rules continue to apply (see the California Building Code sections on glazing in rated assemblies for those specifics). Use the CHBC allowance only where the enforcing agency accepts it under § 8-402.3.
Exceptions & special cases
The CHBC text specifically ties the allowance to one‑hour interior walls; it does not state that historic glazing or unreated wood doors may be accepted in fire barriers or exterior walls requiring higher ratings. If your project involves other types of rated assemblies, you must consult the regular code or the enforcing agency for possible alternatives. § 8-402.3 does not authorize approvals beyond the one‑hour interior‑wall context.
The CHBC refers to automatic sprinkler requirements elsewhere (e.g., § 8-402.1 and § 8-402.2), which in practice means the sprinkler design/type/coverage must meet the CHBC’s accepted sprinkler provisions (see the CHBC references to Section 8-410). Where a sprinkler system is the chosen compliance method, comply with the CHBC sprinkler rules and the enforcing agency’s direction.
Historic glazing that is in areas subject to human impact (e.g., low doors, accessible sidelights) has its own CHBC consideration; § 8-812.1 permits approval subject to the enforcing agency and may require protective measures (film, guards, signage) in addition to the § 8-402.3 conditions.
Common mistakes
Assuming CHBC automatically allows any historic window or door in any rated wall. The CHBC allowance is conditional and limited to one‑hour interior walls and only with smoke seals + sprinklers — do not rely on the preservation clause without meeting both conditions and getting enforcing‑agency approval. § 8-402.3.
Forgetting that the approving authority is the local enforcing agency. The CHBC language is permissive (“may be approved”); documentation of approval and any required mitigation (e.g., specific smoke‑seal details, sprinkler coverage) should be recorded in plan review and inspection. § 8-402.3.
Overlooking other code limits for special situations (elevator enclosures, exterior fire walls, energy‑storage separations). The CHBC allowance does not automatically override regular code restrictions that are outside the cited provision’s scope. If the regular code has a stricter requirement for a particular assembly, consult the enforcing agency.
Confusing fire‑protection/fire‑resistance rated glazing requirements from the regular code with the CHBC historic‑material allowance. For example, the regular code contains specific test, labeling and size rules for fire‑rated glazing (see the California Building Code sections on glazing) — the CHBC option is an alternative only where explicitly allowed and approved by the enforcing agency.
Worked example — concrete scenario
Scenario:
- A qualified historic building has an interior corridor wall that the regular code would require to be one‑hour fire‑rated.
- That corridor wall contains an original wood‑frame 24 in × 36 in operable window with historic glass, and the original solid wood door is non‑rated.
Step‑by‑step application of CHBC:
- Identify the assembly: interior wall required to have one‑hour rating — this matches the scope of § 8-402.3.
- Verify the two CHBC conditions:
- The window and door are operable and can be fitted with appropriate smoke seals (install labeled or approved gasketing/gaskets at meeting edges as necessary). § 8-402.3 requires appropriate smoke seals.
- The corridor and the area affected are provided with an automatic sprinkler system per CHBC sprinkler provisions (the CHBC allows sprinkler‑based alternatives; see § 8-402.1 and § 8-402.2 for sprinkler use as a compliance path).
- Submit these measures to the enforcing agency for approval. If the agency concurs that the smoke seals and sprinkler coverage adequately mitigate the life safety concerns, they may approve retention of the historic glazing and the original solid wood door under § 8-402.3.
Notes on numbers: the 24 × 36 window is 864 square inches, which exceeds common regular‑code 100 sq in limits for some fire‑door vision panels and other specific CBC exceptions; however, § 8-402.3 allows the enforcing agency to approve historic glazing in the one‑hour interior wall context when the CHBC conditions are met — the local approval replaces the need to comply with the regular code’s glazing limits only to the extent the CHBC allows. Always document the jurisdiction’s approval in plan review.
Related provisions
- § 8-402.3 — Openings in fire‑rated systems (controlling provision for historic glazing/doors).
- § 8-402.1 — Exterior wall construction and use of automatic sprinkler systems to satisfy opening protection.
- § 8-402.2 — One‑hour construction exceptions when sprinklers or a life‑safety evaluation are provided.
- § 8-410 — (Referenced by § 8-402.3) CHBC sprinkler provisions — see CHBC cross‑references for sprinkler design and coverage requirements.
- § 8-812.1 — Glazing subject to human impact — CHBC guidance for protective measures for historic glazing.
- California Building Code sections on glazing and fire door/window assemblies (for regular‑code test, labeling and size rules referenced as a comparison and to be used where CHBC does not apply).
Code references
Grounded in the retrieved California Historical Building Code — click a citation to read the verbatim passage:
CHBC § 8-402 High relevance — show source text
SECTION 8-402 — FIRE-RESISTIVE CONSTRUCTION
8-402.1 Exterior wall construction. The fire-resistance requirement for existing exterior walls and existing opening protection may be satisfied when an automatic sprinkler system designed for exposure protection is installed per the CHBC. The automatic sprinklers may be installed on the exterior with at least one sprinkler located over each opening required to be protected. Additional sprinklers shall also be distributed along combustible walls under the roof lines that do not meet the fire-resistive requirement due to relationship to property lines as required by regular code. Such sprinkler systems may be connected to the domestic water supply on the supply-main side of the building shut-off valve. A shut-off valve may be installed for the sprinkler system, provided it is locked in an open position.
8-402.2 One-hour construction. Upgrading an existing qualified historical building or property to one-hour fire-resistive construction and one-hour fire-resistive corridors shall not be required regardless of construction or occupancy when one of the following is provided:
- An automatic sprinkler system throughout. See Section 8-410 for automatic sprinkler systems.
- An approved life safety evaluation.
- Other alternative measures as approved by the enforcing agency.
8-402.3 Openings in fire-rated systems. Historical glazing materials and solid wood unrated doors in interior walls required to have one-hour fire rating may be approved when operable windows and doors are provided with appropriate smoke seals and when the area affected is provided with an automatic sprinkler system. See Section 8-410 for automatic sprinkler systems.
SECTION 8-403 — INTERIOR FINISH MATERIALS
New non-historical interior wall and ceiling finishes shall conform to the provisions of the regular code. Existing non-conforming materials used in interior walls and finishes may be surfaced with an approved fire-retardant to increase the rating of the natural finish to within reasonable proximity of the required rating. For wood lath and plaster walls, see Section 8-404.
Exception: When an automatic sprinkler system is provided throughout the building, existing finishes shall be approved.
SECTION 8-404 — WOOD LATH AND PLASTER
Wood lath and plaster walls may be considered in accordance with codes, standards and listings published prior to 1943 whereby a wood stud wall assembly with gypsum or lime plaster on hand split or sawn wooden lath obtains a one-half-hour fire-resistive rating. This rating may be increased for interior walls to as much as one hour by filling the wall with mineral fiber or glass fiber.
SECTION 8-405 — OCCUPANCY SEPARATION
See Chapter 8-3.
SECTION 8-406 — MAXIMUM FLOOR AREA
See Chapter 8-3.
SECTION 8-407 — VERTICAL SHAFTS
Vertical shafts need not be enclosed when such shafts are blocked at every floor level by the installation of not less than 2 full inches (51 mm) of solid wood or equivalent construction to prevent the initial passage of smoke and flame. Automatic sprinkler systems or other solutions may be considered on a case-by-case basis, in lieu of enclosure of vertical shafts and stairwells.
SECTION 8-408 — ROOF COVERING
Existing or original roofing materials may be repaired or reconstructed subject to the following requirements:
- The original or historical roofing system shall be detailed or modified as necessary in order to be capable of providing shelter while preserving the historical materials and appearance of the roof.
CHBC § 716.1.2.3 High relevance — show source text
Fire-resistance-rated glazing tested to ASTM E119 in accordance with Section 716.1.2.3 shall be permitted, in the maximum size tested.
b. Under the column heading “Fire-rated glazing marking door vision panel,” W refers to the fire-resistance rating of the glazing, not the frame.
c. See Section 716.1.2.2.1 and Table 716.1(1) for additional permitted markings.
d. Two doors, each with a fire protection rating of 11/2 hours, installed on opposite sides of the same opening in a fire wall, shall be deemed equivalent in fire protection rating to
one 3-hour fire door.
e. As required in Section 706.4.
f. As allowed in Section 4.6 of NFPA 221.
g. See Section 716.2.5.1.2.
h. Fire-protection-rated glazing is not permitted for fire barriers required by Section 1207 of the_California Fire Code_ to enclose energy storage systems. Fire-resistance-rated glaz-
ing assemblies tested to ASTM E119 or UL 263, as specified in Section 716.1.2.3, shall be permitted.
i. Two doors, each with a fire rating of 20 minutes, installed on opposite sides of the same opening in a fire partition, shall be deemed equivalent in fire protection rating to one
45-minute fire door.|For SI: 1 square inch = 645.2 mm.
a. Fire-resistance-rated glazing tested to ASTM E119 in accordance with Section 716.1.2.3 shall be permitted, in the maximum size tested.
b. Under the column heading “Fire-rated glazing marking door vision panel,” W refers to the fire-resistance rating of the glazing, not the frame.
c. See Section 716.1.2.2.1 and Table 716.1(1) for additional permitted markings.
d. Two doors, each with a fire protection rating of 11/2 hours, installed on opposite sides of the same opening in a fire wall, shall be deemed equivalent in fire protection rating to
one 3-hour fire door.
e. As required in Section 706.4.
f. As allowed in Section 4.6 of NFPA 221.
g. See Section 716.2.5.1.2.
h. Fire-protection-rated glazing is not permitted for fire barriers required by Section 1207 of the_California Fire Code_ to enclose energy storage systems. Fire-resistance-rated glaz-
ing assemblies tested to ASTM E119 or UL 263, as specified in Section 716.1.2.3, shall be permitted.
i. Two doors, each with a fire rating of 20 minutes, installed on opposite sides of the same opening in a fire partition, shall be deemed equivalent in fire protection rating to one
45-minute fire door.|For SI: 1 square inch = 645.2 mm.
a. Fire-resistance-rated glazing tested to ASTM E119 in accordance with Section 716.1.2.3 shall be permitted, in the maximum size tested.
b. Under the column heading “Fire-rated glazing marking door vision panel,” W refers to the fire-resistance rating of the glazing, not the frame.
c. See Section 716.1.2.2.1 and Table 716.1(1) for additional permitted markings.
d.CHBC § 8-303.6 High relevance — show source text
8-303.6 Light and ventilation. Windows in habitable rooms shall have an area of 6 percent of the floor area, or 6 square feet (0.56 m [2] ), whichever is greater. Windows in sleeping rooms shall be openable (see Section 8-503). Residential occupancies need not be provided with electrical lighting.
8-303.7 Alteration and repair. The alteration and repair of qualified historical buildings or properties may permit the replacement, retention and extension of original materials and the continued use of original methods of construction, provided a life safety hazard is not created or continued. Alterations and repairs shall be consistent with the CHBC.
The amount of alterations and repairs is not limited, provided there is no nonhistorical increase in floor area, volume or size of the building or property.
8-303.8 Exiting. See Chapter 8-5.
6 2025 CALIFORNIA HISTORICAL BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
8-4 FIRE PROTECTION
SECTION 8-401 — PURPOSE, INTENT AND SCOPE
8-401.1 Purpose. The purpose of this chapter is to provide regulations for fire protection of qualified historical buildings or properties. The CHBC requires enforcing agencies to accept any reasonably equivalent alternatives to the regular code when dealing with qualified historical buildings or properties.
8-401.2 Intent. The intent of the CHBC is to preserve the integrity of qualified historical buildings or properties while maintaining a reasonable degree of fire protection based primarily on the life safety of the occupants and firefighting personnel.
8-401.3 Scope. This chapter shall apply when required by the provisions of Section 8-102.
SECTION 8-402 — FIRE-RESISTIVE CONSTRUCTION
8-402.1 Exterior wall construction. The fire-resistance requirement for existing exterior walls and existing opening protection may be satisfied when an automatic sprinkler system designed for exposure protection is installed per the CHBC. The automatic sprinklers may be installed on the exterior with at least one sprinkler located over each opening required to be protected. Additional sprinklers shall also be distributed along combustible walls under the roof lines that do not meet the fire-resistive requirement due to relationship to property lines as required by regular code. Such sprinkler systems may be connected to the domestic water supply on the supply-main side of the building shut-off valve. A shut-off valve may be installed for the sprinkler system, provided it is locked in an open position.
8-402.2 One-hour construction. Upgrading an existing qualified historical building or property to one-hour fire-resistive construction and one-hour fire-resistive corridors shall not be required regardless of construction or occupancy when one of the following is provided:
- An automatic sprinkler system throughout. See Section 8-410 for automatic sprinkler systems.
- An approved life safety evaluation.
- Other alternative measures as approved by the enforcing agency.
8-402.3 Openings in fire-rated systems. Historical glazing materials and solid wood unrated doors in interior walls required to have one-hour fire rating may be approved when operable windows and doors are provided with appropriate smoke seals and when the area affected is provided with an automatic sprinkler system. See Section 8-410 for automatic sprinkler systems.
SECTION 8-403 — INTERIOR FINISH MATERIALS
CHBC § 3006.3. High relevance — show source text
Exception: Elevator hoistway door openings protected in accordance with Section 3006.3.
716.2.2.2 Door assemblies in other fire partitions. Fire door assemblies required to have a minimum fire protection rating of 20 minutes where located in other fire partitions having a fire-resistance rating of 0.5 hour in accordance with Table 716.1(2) shall be tested in accordance with NFPA 252, UL 10B or UL 10C with the hose stream test.
716.2.2.3 Doors in interior exit stairways and ramps and exit passageways. Fire door assemblies in interior exit stairways and ramps and exit passageways shall have a maximum transmitted temperature rise of not more than 450°F (250°C) above ambient at the end of 30 minutes of standard fire test exposure.
Exception: The maximum transmitted temperature rise is not required in buildings equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1 or 903.3.1.2. 716.2.2.3.1 Glazing in doors. Fire-protection-rated glazing in excess of 100 square inches (0.065 m [2] ) is not permitted. Fireresistance-rated glazing in excess of 100 square inches (0.065 m [2] ) shall be permitted in fire doors. Listed fire-resistance-rated glazing in a fire door shall have a maximum transmitted temperature rise in accordance with Section 716.2.2.3 when the fire door is tested in accordance with NFPA 252, UL 10B or UL 10C.
716.2.3 Fire doors. Fire doors installed within a fire door assembly shall meet the fire rating indicated in Table 716.1(2).
716.2.4 Fire door frames. Fire door frames installed as part of a fire door assembly shall meet the fire rating indicated in Table 716.1(2).
716.2.5 Glazing in fire door assemblies. Fire-rated glazing conforming to the opening protection requirements in Section 716.2.1 shall be permitted in fire door assemblies.
716.2.5.1 Size limitations. Fire-resistance-rated glazing shall comply with the size limitations in Section 716.2.5.1.1. Fireprotection-rated glazing shall comply with the size limitations of NFPA 80, and as provided in Section 716.2.5.1.2.
716.2.5.1.1 Fire-resistance-rated glazing in door assemblies in fire walls and fire barriers rated greater than 1 hour. Fire-resistance-rated glazing tested to ASTM E119 or UL 263 and NFPA 252, UL 10B or UL 10C shall be permitted in fire door assemblies located in fire walls and in fire barriers in accordance with Table 716.1(2) to the maximum size tested and in accordance with their listings.
716.2.5.1.2 Fire-protection-rated glazing in door assemblies in fire walls and fire barriers rated greater than 1 hour. Fire-protection-rated glazing shall be prohibited in fire walls and fire barriers except as provided in Sections 716.2.5.1.2.1 and 716.2.5.1.2.2.
CHBC § 716.2.5.1.2. High relevance — show source text
See Section 716.2.5.1.2.
h. Fire-protection-rated glazing is not permitted for fire barriers required by Section 1207 of the_California Fire Code_ to enclose energy storage systems. Fire-resistance-rated glaz-
ing assemblies tested to ASTM E119 or UL 263, as specified in Section 716.1.2.3, shall be permitted.
i. Two doors, each with a fire rating of 20 minutes, installed on opposite sides of the same opening in a fire partition, shall be deemed equivalent in fire protection rating to one
45-minute fire door.|For SI: 1 square inch = 645.2 mm.
a. Fire-resistance-rated glazing tested to ASTM E119 in accordance with Section 716.1.2.3 shall be permitted, in the maximum size tested.
b. Under the column heading “Fire-rated glazing marking door vision panel,” W refers to the fire-resistance rating of the glazing, not the frame.
c. See Section 716.1.2.2.1 and Table 716.1(1) for additional permitted markings.
d. Two doors, each with a fire protection rating of 11/2 hours, installed on opposite sides of the same opening in a fire wall, shall be deemed equivalent in fire protection rating to
one 3-hour fire door.
e. As required in Section 706.4.
f. As allowed in Section 4.6 of NFPA 221.
g. See Section 716.2.5.1.2.
h. Fire-protection-rated glazing is not permitted for fire barriers required by Section 1207 of the_California Fire Code_ to enclose energy storage systems. Fire-resistance-rated glaz-
ing assemblies tested to ASTM E119 or UL 263, as specified in Section 716.1.2.3, shall be permitted.
i. Two doors, each with a fire rating of 20 minutes, installed on opposite sides of the same opening in a fire partition, shall be deemed equivalent in fire protection rating to one
45-minute fire door.|For SI: 1 square inch = 645.2 mm.
a. Fire-resistance-rated glazing tested to ASTM E119 in accordance with Section 716.1.2.3 shall be permitted, in the maximum size tested.
b. Under the column heading “Fire-rated glazing marking door vision panel,” W refers to the fire-resistance rating of the glazing, not the frame.
c. See Section 716.1.2.2.1 and Table 716.1(1) for additional permitted markings.
d. Two doors, each with a fire protection rating of 11/2 hours, installed on opposite sides of the same opening in a fire wall, shall be deemed equivalent in fire protection rating to
one 3-hour fire door.
e. As required in Section 706.4.
f. As allowed in Section 4.6 of NFPA 221.
g. See Section 716.2.5.1.2.
h. Fire-protection-rated glazing is not permitted for fire barriers required by Section 1207 of the_California Fire Code_ to enclose energy storage systems. Fire-resistance-rated glaz-
ing assemblies tested to ASTM E119 or UL 263, as specified in Section 716.1.2.3, shall be permitted.
i.CHBC § 716.2.3 High relevance — show source text
716.2.3 Fire doors. Fire doors installed within a fire door assembly shall meet the fire rating indicated in Table 716.1(2).
716.2.4 Fire door frames. Fire door frames installed as part of a fire door assembly shall meet the fire rating indicated in Table 716.1(2).
716.2.5 Glazing in fire door assemblies. Fire-rated glazing conforming to the opening protection requirements in Section 716.2.1 shall be permitted in fire door assemblies.
716.2.5.1 Size limitations. Fire-resistance-rated glazing shall comply with the size limitations in Section 716.2.5.1.1. Fireprotection-rated glazing shall comply with the size limitations of NFPA 80, and as provided in Section 716.2.5.1.2.
716.2.5.1.1 Fire-resistance-rated glazing in door assemblies in fire walls and fire barriers rated greater than 1 hour. Fire-resistance-rated glazing tested to ASTM E119 or UL 263 and NFPA 252, UL 10B or UL 10C shall be permitted in fire door assemblies located in fire walls and in fire barriers in accordance with Table 716.1(2) to the maximum size tested and in accordance with their listings.
716.2.5.1.2 Fire-protection-rated glazing in door assemblies in fire walls and fire barriers rated greater than 1 hour. Fire-protection-rated glazing shall be prohibited in fire walls and fire barriers except as provided in Sections 716.2.5.1.2.1 and 716.2.5.1.2.2.
716.2.5.1.2.1 Horizontal exits. Fire-protection-rated glazing shall be permitted as vision panels in self-closing swinging fire door assemblies serving as horizontal exits in fire walls where limited to 100 square inches (0.065 m [2] ). 716.2.5.1.2.2 Fire barriers. Fire-protection-rated glazing shall be permitted in fire doors having a 1 [1] / 2 -hour fire protection rating intended for installation in fire barriers, where limited to 100 square inches (0.065 m [2] ).
2025 CALIFORNIA BUILDING CODE 7-31
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
FIRE AND SMOKE PROTECTION FEATURES
716.2.5.2 Elevator, stairway and ramp protectives. Approved fire-protection-rated glazing used in fire door assemblies in elevator, stairway and ramp enclosures shall be so located as to furnish clear vision of the passageway or approach to the elevator, stairway or ramp.
716.2.5.3 Glazing in door assemblies in corridors and smoke barriers. In a 20-minute fire door assembly, the glazing material in the door itself shall have a minimum fire-protection-rated glazing of 20 minutes and shall be exempt from the hose stream test.
CHBC § 716.1.2.3 High relevance — show source text
Fire-resistance-rated glaz-
ing assemblies tested to ASTM E119 or UL 263, as specified in Section 716.1.2.3, shall be permitted.
i. Two doors, each with a fire rating of 20 minutes, installed on opposite sides of the same opening in a fire partition, shall be deemed equivalent in fire protection rating to one
45-minute fire door.|For SI: 1 square inch = 645.2 mm.
a. Fire-resistance-rated glazing tested to ASTM E119 in accordance with Section 716.1.2.3 shall be permitted, in the maximum size tested.
b. Under the column heading “Fire-rated glazing marking door vision panel,” W refers to the fire-resistance rating of the glazing, not the frame.
c. See Section 716.1.2.2.1 and Table 716.1(1) for additional permitted markings.
d. Two doors, each with a fire protection rating of 11/2 hours, installed on opposite sides of the same opening in a fire wall, shall be deemed equivalent in fire protection rating to
one 3-hour fire door.
e. As required in Section 706.4.
f. As allowed in Section 4.6 of NFPA 221.
g. See Section 716.2.5.1.2.
h. Fire-protection-rated glazing is not permitted for fire barriers required by Section 1207 of the_California Fire Code_ to enclose energy storage systems. Fire-resistance-rated glaz-
ing assemblies tested to ASTM E119 or UL 263, as specified in Section 716.1.2.3, shall be permitted.
i. Two doors, each with a fire rating of 20 minutes, installed on opposite sides of the same opening in a fire partition, shall be deemed equivalent in fire protection rating to one
45-minute fire door.|For SI: 1 square inch = 645.2 mm.
a. Fire-resistance-rated glazing tested to ASTM E119 in accordance with Section 716.1.2.3 shall be permitted, in the maximum size tested.
b. Under the column heading “Fire-rated glazing marking door vision panel,” W refers to the fire-resistance rating of the glazing, not the frame.
c. See Section 716.1.2.2.1 and Table 716.1(1) for additional permitted markings.
d. Two doors, each with a fire protection rating of 11/2 hours, installed on opposite sides of the same opening in a fire wall, shall be deemed equivalent in fire protection rating to
one 3-hour fire door.
e. As required in Section 706.4.
f. As allowed in Section 4.6 of NFPA 221.
g. See Section 716.2.5.1.2.
h. Fire-protection-rated glazing is not permitted for fire barriers required by Section 1207 of the_California Fire Code_ to enclose energy storage systems. Fire-resistance-rated glaz-
ing assemblies tested to ASTM E119 or UL 263, as specified in Section 716.1.2.3, shall be permitted.
i. Two doors, each with a fire rating of 20 minutes, installed on opposite sides of the same opening in a fire partition, shall be deemed equivalent in fire protection rating to one
45-minute fire door.|For SI: 1 square inch = 645.2 mm.
a.CHBC § 716.3.2 High relevance — show source text
716.3.2 Performance requirements. Fire window assemblies shall be installed in the assemblies and comply with the fire protection rating specified in Table 716.1(3).
716.3.2.1 Interior fire window assemblies. Fire-protection-rated glazing used in fire window assemblies located in fire partitions and fire barriers shall be limited to use in assemblies with a maximum fire-resistance rating of 1 hour in accordance with this section.
716.3.2.1.1 Where [3] / 4 -hour-fire-protection window assemblies permitted. Fire-protection-rated glazing requiring 45minute opening protection in accordance with Table 716.1(3) shall be limited to fire partitions designed in accordance with Section 708 and fire barriers utilized in the applications set forth in Sections 707.3.6, 707.3.7 and 707.3.9 where the fire-resistance rating does not exceed 1 hour. Fire-resistance-rated glazing assemblies tested in accordance with ASTM E119 or UL 263 shall not be subject to the limitations of this section.
716.3.2.1.1.1 Energy storage system separation. Fire-protection-rated glazing is not permitted for use in fire window assemblies in fire barriers required by Section 1207 of the California Fire Code to enclose energy storage systems.
716.3.2.1.2 Area limitations. The total area of the glazing in fire-protection-rated window assemblies shall not exceed 25 percent of the area of a common wall with any room.
2025 CALIFORNIA BUILDING CODE 7-33
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
FIRE AND SMOKE PROTECTION FEATURES
716.3.2.1.3 Where [1] / 3 -hour-fire-protection window assemblies permitted. Fire-protection-rated glazing shall be permitted in window assemblies tested to NFPA 257 or UL 9 in fire partitions requiring [1] / 3 -hour opening protection in accordance with Table 716.1(3).
716.3.3 Fire window frames. Fire window frames installed with a fire window assembly shall meet the fire-protection rating indicated in Table 716.1(3).
716.3.3.1 Window mullions. Metal mullions that exceed a nominal height of 12 feet (3658 mm) shall be protected with materials to afford the same fire-resistance rating as required for the wall construction in which the protective is located.
716.3.4 Fire-protection-rated glazing. Glazing in fire window assemblies shall be fire protection rated in accordance with this section and Table 716.1(3). Fire-protection-rated glazing in fire window assemblies shall be tested in accordance with and shall meet the acceptance criteria of NFPA 257 or UL 9. Openings in nonfire-resistance-rated exterior wall assemblies that require protection in accordance with Section 705.3, 705.9, 705.9.5 or 705.9.6 shall have a fire protection rating of not less than [3] / 4 hour. Fire-protection-rated glazing in [1] / 2 -hour fire-resistance-rated partitions is permitted to have a 20-minute fire protection rating.
716.3.4.1 Glass and glazing. Glazing in fire window assemblies shall be fire-protection-rated glazing installed in accordance with and complying with the size limitations set forth in NFPA 80.
CHBC § 716.3.2.1.3 High relevance — show source text
716.3.2.1.3 Where [1] / 3 -hour-fire-protection window assemblies permitted. Fire-protection-rated glazing shall be permitted in window assemblies tested to NFPA 257 or UL 9 in fire partitions requiring [1] / 3 -hour opening protection in accordance with Table 716.1(3).
716.3.3 Fire window frames. Fire window frames installed with a fire window assembly shall meet the fire-protection rating indicated in Table 716.1(3).
716.3.3.1 Window mullions. Metal mullions that exceed a nominal height of 12 feet (3658 mm) shall be protected with materials to afford the same fire-resistance rating as required for the wall construction in which the protective is located.
716.3.4 Fire-protection-rated glazing. Glazing in fire window assemblies shall be fire protection rated in accordance with this section and Table 716.1(3). Fire-protection-rated glazing in fire window assemblies shall be tested in accordance with and shall meet the acceptance criteria of NFPA 257 or UL 9. Openings in nonfire-resistance-rated exterior wall assemblies that require protection in accordance with Section 705.3, 705.9, 705.9.5 or 705.9.6 shall have a fire protection rating of not less than [3] / 4 hour. Fire-protection-rated glazing in [1] / 2 -hour fire-resistance-rated partitions is permitted to have a 20-minute fire protection rating.
716.3.4.1 Glass and glazing. Glazing in fire window assemblies shall be fire-protection-rated glazing installed in accordance with and complying with the size limitations set forth in NFPA 80.
716.3.5 Labeled protective assemblies. Glazing in fire window assemblies shall be labeled by an approved agency. The labels shall comply with NFPA 80 and Section 716.3.5.2.
716.3.5.1 Fire window frames. Fire window frames shall be approved for the intended application.
716.3.5.2 Labeling requirements. Fire-protection-rated glazing shall bear a label or other identification showing the name of the manufacturer, the test standard and information required in Section 716.1.2.2.2 and Table 716.1(3) that shall be issued by an approved agency and permanently identified on the glazing.
716.3.6 Installation. Fire window assemblies shall be installed in accordance with the provisions of this section.
716.3.6.1 Closure. Fire-protection-rated glazing shall be in the fixed position or be automatic-closing and shall be installed in labeled frames.
716.4 Fire protective curtain assembly. Approved fire protective curtain assemblies shall be constructed of any materials or assembly of component materials tested without hose stream in accordance with UL 10D, and shall comply with the Sections 716.4.1 through 716.4.3.
716.4.1 Label. Fire protective curtain assemblies used as opening protectives in fire-rated walls and smoke partitions shall be labeled in accordance with Section 716.2.9.
716.4.2 Smoke and draft control. Fire protective curtain assemblies used to protect openings where smoke and draft control assemblies are required shall comply with Section 716.2.1.4.
716.4.3 Installation. Fire protective curtain assemblies shall be installed in accordance with NFPA 80.
SECTION 717—DUCTS AND AIR TRANSFER OPENINGS
CHBC § 716.2.5.1.2 High relevance — show source text
716.2.5.1.2 Fire-protection-rated glazing in door assemblies in fire walls and fire barriers rated greater than 1 hour. Fire-protection-rated glazing shall be prohibited in fire walls and fire barriers except as provided in Sections 716.2.5.1.2.1 and 716.2.5.1.2.2.
716.2.5.1.2.1 Horizontal exits. Fire-protection-rated glazing shall be permitted as vision panels in self-closing swinging fire door assemblies serving as horizontal exits in fire walls where limited to 100 square inches (0.065 m [2] ). 716.2.5.1.2.2 Fire barriers. Fire-protection-rated glazing shall be permitted in fire doors having a 1 [1] / 2 -hour fire protection rating intended for installation in fire barriers, where limited to 100 square inches (0.065 m [2] ).
2025 CALIFORNIA BUILDING CODE 7-31
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
FIRE AND SMOKE PROTECTION FEATURES
716.2.5.2 Elevator, stairway and ramp protectives. Approved fire-protection-rated glazing used in fire door assemblies in elevator, stairway and ramp enclosures shall be so located as to furnish clear vision of the passageway or approach to the elevator, stairway or ramp.
716.2.5.3 Glazing in door assemblies in corridors and smoke barriers. In a 20-minute fire door assembly, the glazing material in the door itself shall have a minimum fire-protection-rated glazing of 20 minutes and shall be exempt from the hose stream test.
716.2.5.4 Fire door frames with transom lights and sidelights. Fire-protection-rated glazing shall be permitted in door frames with transom lights, sidelights or both, where a [3] / 4 -hour fire protection rating or less is required and in 2-hour fire-resistance-rated exterior walls in accordance with Table 716.1(2). Fire door frames with transom lights, sidelights or both, installed with fire-resistance-rated glazing tested as an assembly in accordance with ASTM E119 or UL 263 shall be permitted where a fire protection rating exceeding [3] / 4 hour is required in accordance with Table 716.1(2).
716.2.5.4.1 Energy storage system separation. Fire-protection-rated glazing shall not be permitted in fire door frames with transom lights and sidelights in fire barriers required by Section 1207 of the California Fire Code to enclose energy storage systems.
716.2.6 Fire door hardware and closers. Fire door hardware and closers shall be installed on fire door assemblies in accordance with the requirements of this section.
716.2.6.1 Door closing. Fire doors shall be latching and self- or automatic-closing in accordance with this section.
Exceptions:
- Fire doors located in common walls separating dwelling units or sleeping units in Group R-1 shall be permitted without automatic- or self-closing devices.
- The elevator car doors and the associated elevator hoistway doors at the floor level designated for recall in accordance with Section 3003.2 shall be permitted to remain open during Phase I emergency recall operation.
- Fire doors required solely for compliance with ICC 500 shall not be required to be self-closing or automatic-closing.
CHBC § 8-812.1 High relevance — show source text
8-812.1 Glazing subject to human impact. Historical glazing material located in areas subject to human impact may be approved subject to the concurrence of the enforcing agency when alternative protective measures are provided. These measures may include, but not be limited to, additional glazing panels, protective film, protective guards or systems, and devices or signs which would provide adequate public safety.
8-812.2 Glazing in fire-rated systems. See Section 8-402.3.
TABLE8-8A—STRENGTH VALUES FOR EXISTING MATERIALS Col2 EXISTING MATERIALS OR CONFIGURATIONS OF MATERIALS1 STRENGTH LEVEL CAPACITY
x14.594 for N/m1. Horizontal diaphragms2
1.1. Roofs with straight sheathing and roofing applied directly to the sheathing
1.2. Roofs with diagonal sheathing and roofing applied directly to the sheathing
1.3. Floors with straight tongue-and-groove sheathing
1.4. Floors with straight sheathing and finished wood flooring with board edges
offset or perpendicular
1.5. Floors with diagonal sheathing and finished300 lbs per foot for seismic shear
750 lbs per foot for seismic shear
300 lbs per foot for seismic shear
1,500 lbs per foot for seismic shear
1,800 lbs per foot for seismic shear2. Crosswalls2,3
2.1. Plaster on wood or metal lath
2.2. Plaster on gypsum lath
2.3. Gypsum wallboard, unblocked edges
2.4. Gypsum wallboard, blocked edgesPer side: 600 lbs per foot for seismic shear
550 lbs per foot for seismic shear
200 lbs per foot for seismic shear
400 lbs per foot for seismic shear3. Existing footings, wood framing, structural steel and reinforcing steel
3.1. Plain concrete footings
3.2. Douglas fir wood
3.3. Reinforcing steel
3.4. Structural steelf ′c = 1,500 psi (10.34 MPa) unless otherwise shown by
tests3
Allowable stress same as D.F. No. 13
_ft _= 40,000 lbs per square inch (124.1 N/mm2) maximum
ft= 33,000 lbs per square inch (137.9 N/mm2) maximum1. Material must be sound and in good condition.
2. Shear values of these materials may be combined, except the total combined value shall not exceed 900 pounds per foot (13,140 N/m).
3. Stresses given may be increased for combinations of loads as specified in the regular code.1. Material must be sound and in good condition.
2. Shear values of these materials may be combined, except the total combined value shall not exceed 900 pounds per foot (13,140 N/m).
3. Stresses given may be increased for combinations of loads as specified in the regular code.2025 CALIFORNIA HISTORICAL BUILDING CODE 17
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
ARCHAIC MATERIALS AND METHODS OF CONSTRUCTION
CHBC § 716.1.2.3.1 High relevance — show source text
716.1.2.3.1 Glazing in fire door and fire window assemblies. Fire-resistance-rated glazing shall be permitted in fire door and fire window assemblies where tested and installed in accordance with their listings and where in compliance with the requirements of this section.
716.2 Fire door assemblies. Fire door assemblies required by other sections of this code shall comply with the provisions of this section. Fire door frames with transom lights, sidelights or both shall be permitted in accordance with Section 716.2.5.4.
716.2.1 Testing requirements. Approved fire door and fire shutter assemblies shall be constructed of any material or assembly of component materials that conforms to the test requirements of Sections 716.2.1.1 through 716.2.1.4 and the fire protection rating indicated in Table 716.1(2).
Exceptions:
Labeled protective assemblies that conform to the requirements of this section or UL 10A, UL 14B and UL 14C for tinclad fire door assemblies.
Floor fire door assemblies in accordance with Section 712.1.13.1.
716.2.1.1 Side-hinged or pivoted swinging doors. Fire door assemblies with side-hinged and pivoted swinging doors shall be tested in accordance with NFPA 252 or UL 10C. For tests conducted in accordance with NFPA 252, the fire test shall be conducted using the positive pressure method specified in the standard.
716.2.1.2 Other types of assemblies. Fire door assemblies with other types of doors, including swinging elevator doors, horizontal sliding fire doors, rolling steel fire doors, fire shutters, bottom- and side-hinged chute intake doors, and top-hinged chute discharge doors, shall be tested in accordance with NFPA 252 or UL 10B. For tests conducted in accordance with NFPA 252, the neutral pressure plane in the furnace shall be maintained as nearly equal to the atmospheric pressure as possible at the top of the door, as specified in the standard.
716.2.1.3 Glazing in transoms lights and sidelights in corridors and smoke barriers. Glazing material in any other part of the door assembly, including transom lights and sidelights, shall be tested in accordance with NFPA 257 or UL 9, including the hose stream test, in accordance with Section 716.3.1.1.
716.2.1.4 Smoke and draft control. Fire door assemblies that serve as smoke and draft control assemblies shall be tested in
accordance with UL 1784.
7-30 2025 CALIFORNIA BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
FIRE AND SMOKE PROTECTION FEATURES
716.2.2 Performance requirements. Fire door assemblies shall be installed in the assemblies specified in Table 716.1(2) and shall comply with the fire protection rating specified.
716.2.2.1 Door assemblies in corridors and smoke barriers. Fire door assemblies required to have a minimum fire protection rating of 20 minutes where located in corridor walls or smoke barrier walls having a fire-resistance rating in accordance with Table 716.1(2) shall be tested in accordance with NFPA 252 or UL 10C without the hose stream test.
Frequently asked questions
Can any historic window or original door always stay in a one‑hour fire wall under the CHBC?
Not automatically. § 8-402.3 requires that the openings be operable with appropriate smoke seals and that the area be sprinklered; approval is subject to the enforcing agency’s review and acceptance.
Who is the approving authority?
The local enforcing agency — the CHBC language indicates the agency may approve historic glazing and unrated solid wood doors under the stated conditions in § 8-402.3.
Does the CHBC allowance override regular code size or labeling limits for fire‑rated glazing?
The CHBC provides a limited preservation alternative for qualified historical buildings under § 8-402.3. For assemblies or situations not covered by the CHBC provision, or where the enforcing agency does not grant approval, the regular code’s labeling, testing and size limits continue to apply (see the California Building Code provisions on fire glazing).
Are transoms, sidelights, and vision panels treated the same?
If they are part of an interior wall required to have a one‑hour rating, the CHBC language covers “historical glazing materials” in openings; however, the enforcing agency will evaluate each element for smoke sealing and sprinkler protection. For special cases (e.g., elevator enclosures, energy storage separations) other code limits may control. § 8-402.3 and § 8-812.1 guide the review.
If my project uses § 8-402.3, what paperwork should I include with plan submittal?
Provide drawings/specs showing operability and smoke‑seal details for the historic openings, a sprinkler coverage plan confirming the affected area is protected (per CHBC sprinkler provisions), and a narrative requesting CHBC approval under § 8-402.3. Expect the enforcing agency to document conditions of approval.
More in California Historical Building Code
Ask about the CHBC
Get cited, plain-English answers on the California Historical Building Code for your project — any code section, any scenario.
Start Free Trial