CHBC · California Historical Building Code
When are historical plumbing fixtures allowed or acceptable?
If your building is a qualified historical property, the CHBC explicitly permits original, salvage, or historically accurate reproduction water closets, urinals and flushometer valves— including nonlow‑consumption types—unless a historically accurate fixture that already meets current code exists. The local enforcing agency may still require tests or changes if the fixture or plumbing creates a safety or health hazard.
Last reviewed: July 6, 2026
What the code requires — 2–4 sentences
The CHBC allows the reuse or installation of original, salvage, or historically accurate reproduction plumbing fixtures—specifically water closets, urinals and flushometer valves—in qualified historical buildings unless a historically accurate fixture that also meets the regular (current) code is available. This permission is stated in § 8-903.2.7 of the CHBC. The CHBC still requires that plumbing systems avoid safety hazards and that the enforcing agency may require alternatives or tests where systems depart from the regular code (see § 8-903.1.2 and § 8-903.1.3).
The single most important rule: original, salvage, or historically accurate reproduction water closets, urinals and flushometer valves are permitted in a qualified historical building unless a historically accurate fixture that meets the regular code exists. (§ 8-903.2.7)
Requirements in detail
Key terms (first-use)
- Qualified historical building — a building eligible to use the CHBC; the CHBC applies only when the structure is qualified under Part 8. (See §§ 8-101–8-102 for CHBC application and qualifications.)
- Original / salvage — existing historic fixtures recovered from the building or other historic sources; CHBC explicitly permits these for certain fixtures (§ 8-903.2.7).
- Historically accurate reproduction — new fixtures made to match historic appearance; allowed even if they are nonlow-consumption (i.e., they may use more water than modern low-consumption fixtures) (§ 8-903.2.7).
- Flushometer valve — a valve that discharges a predetermined quantity of water to fixtures and is actuated by water pressure (definition in the Plumbing Code).
What the CHBC actually permits (decision dimensions)
| Decision dimension | What the CHBC allows | When this matters | Code reference |
|---|---|---|---|
| Fixture types | Original, salvage, or historically accurate reproduction water closets, urinals, flushometer valves are permitted. | Use when restoring/retaining historic restroom fixtures. | § 8-903.2.7 |
| Consumption (water use) | Nonlow-consumption historically accurate reproductions are allowed. | Where preservation would otherwise force low-consumption modern fixtures that alter appearance. | § 8-903.2.7 |
| When NOT allowed | If a historically accurate fixture that also complies with the regular code is available, the CHBC’s allowance for higher‑consumption or noncompliant historic fixtures does not apply. | Enforcing agency will require the historically accurate, code‑compliant option if available. | § 8-903.2.7 |
| Safety hazards | Existing systems that, in the enforcing agency’s opinion, constitute a safety hazard may not remain; conversely, existing nonhazardous systems may remain in use. | Safety overrides preservation where life/health risk exists. | § 8-903.1.2 |
| Agency alternatives & tests | The enforcing agency may approve alternatives or require operational tests when systems depart from the regular code. | When historic fixtures are retained but plumbing connections, drainage, or venting differ from current standards. | § 8-903.1.3 and § 8-903.4 |
| Water supply to fixtures | Hot or cold running water is not required for each fixture provided enough water is supplied for normal operation. | Allows retention of historic basins/sinks that were not originally plumbed with full hot/cold service. | § 8-903.2.5 |
| Fixture spout height | Bathtubs and lavatories with filler spouts less than 1 inch (25.4 mm) above the rim may remain in use if an acceptable overflow exists. | Addresses eccentric historic fixture dimensions. | § 8-903.2.6 |
| Materials & nonhistorical work | New nonhistorical materials must meet the regular code; the enforcing agency must accept alternatives that do not create a safety hazard. | When new parts are needed to make historic fixtures work safely. | § 8-903.3 |
How the enforcing agency fits in
- The enforcing agency has discretion to judge safety hazards and may require operational testing or insist on code‑compliant alternatives where necessary (§ 8-903.1.2, § 8-903.1.3, § 8-903.4).
- Where novel or borderline solutions are proposed the local authority can consult or refer to the State Historical Building Safety Board (SHBSB) for review per CHBC appeal/consultation procedures.
Exceptions & special cases
- The explicit CHBC exception: historical or reproduction fixtures are permitted “except where historically accurate fixtures that comply with the regular code are available.” If a historically accurate fixture exists that meets the regular code, the code‑compliant fixture must be used (§ 8-903.2.7).
- Existing plumbing that is archaic but not hazardous may remain in place even if it does not meet current prescriptive standards (§ 8-903.1.2; § 8-903.7.2).
- The CHBC is performance‑oriented: even when historic fixtures are allowed, the system as a whole must not create a safety hazard; the enforcing agency can require tests or modifications to drainage/venting (§ 8-903.4).
Common mistakes
- Assuming the CHBC permits historic fixtures in non‑qualified buildings. The CHBC applies only to qualified historical buildings or properties — verify the building’s qualification before relying on CHBC relief.
- Overlooking the phrase “except where historically accurate fixtures that comply with the regular code are available.” If compliant historic fixtures exist, the allowance for nonlow‑consumption or noncompliant reproductions does not apply. (§ 8-903.2.7)
- Forgetting safety review: some historic fixtures (or their installations) can create health or plumbing hazards; the enforcing agency may require replacement or remediation despite historic value (§ 8-903.1.2).
- Not coordinating with local health department or other authorities when alternative sewage disposal or fixture locations are involved (see related CHBC sections for toilet facility location and alternative sewage disposal).
Worked example — concrete scenario
Scenario: A historic downtown hotel (a qualified historic property) is restoring a men’s restroom. The original flushometer urinals and high‑volume flushometer valves remain; they flush at approximately 3.5 gallons per flush (gpf), while modern low‑consumption urinals are typically 0.5–1.0 gpf. The owner wants to reuse the original flushometers for authenticity.
How CHBC applies:
- Because the building is a qualified historical building, reuse of original/salvage flushometer valves is explicitly permitted under § 8-903.2.7, including nonlow‑consumption reproductions or originals, unless a historically accurate fixture that also complies with the regular code is available.
- The enforcing agency will evaluate whether keeping the high‑volume flushometer creates a safety or public‑health hazard (e.g., sewer capacity or cross‑connection risk). If the agency deems no safety hazard, they may allow the original fixtures to remain per § 8-903.1.2.
- If a historically accurate urinal that meets the current plumbing code (including water‑use standards or backflow prevention required by the regular code) is available, the enforcing agency could require that fixture instead (§ 8-903.2.7).
- The hotel should be prepared to submit documentation and possibly operational tests of drainage/venting or water distribution if requested by the authority (§ 8-903.4, § 8-903.1.3).
(Notes: the example’s gpf figures are illustrative; CHBC does not prescribe gpf values in § 8-903.2.7 — the regulatory determination rests on historic accuracy and safety as described above.)
Related provisions
- § 8-903.1.1 — CHBC scope: applies to acceptance, location, installation, alteration, repair, relocation, replacement or addition of plumbing in a historical building.
- § 8-903.1.2 — Existing systems which do not constitute a safety hazard may remain in use.
- § 8-903.1.3 — Enforcing agency may approve alternatives achieving equivalent life safety.
- § 8-903.2.5 — Hot or cold running water is not required for each plumbing fixture if sufficient water for normal operation is supplied.
- § 8-903.2.6 — Bathtubs and lavatories with filler spouts less than 1 inch (25.4 mm) above the rim may remain if acceptable overflow exists.
- § 8-903.3 — New nonhistorical materials must comply with regular code; alternative materials accepted if not a safety hazard.
- § 8-903.4 — Drainage and vent systems; agency may require operational tests.
- CHBC application and qualification: § 8-101 – § 8-102 — CHBC intent and when it applies (qualified historical buildings/properties).
Code references
Grounded in the retrieved California Historical Building Code — click a citation to read the verbatim passage:
CHBC § 8-902.8.1 High relevance — show source text
MECHANICAL, PLUMBING AND ELECTRICAL REQUIREMENTS
8-902.8.1 Ventilating systems shall be installed so that no safety hazard is created.
8-902.8.2 Grease hoods and grease hood exhaust systems shall be furnished and installed in accordance with applicable requirements of the regular code. Existing systems which are altered shall comply with the regular code.
8-902.9 Miscellaneous equipment requirements.
8-902.9.1 The following appliances and equipment shall be installed so that no safety hazard is created: warm air furnaces, space heating equipment, vented decorative appliances, floor furnaces, vented wall furnaces, unit heaters, room heaters, absorption units, refrigeration equipment, duct furnaces, infrared radiant heaters, domestic incinerators, miscellaneous heat-producing appliances and water heaters.
8-902.9.2 Storage-type water heaters shall be equipped with a temperature- and pressure-relief valve in accordance with applicable requirements of the regular code.
SECTION 8-903 — PLUMBING
8-903.1 General. Plumbing systems shall comply with the regular code unless otherwise noted.
8-903.1.1 The provisions of the CHBC shall apply to the acceptance, location, installation, alteration, repair, relocation, replacement or addition of any plumbing system or equipment within or attached to a historical building.
8-903.1.2 Existing systems which do not, in the opinion of the enforcing agency, constitute a safety hazard may remain in use.
8-903.1.3 The enforcing agency may approve any alternative to these regulations which achieves reasonably equivalent life safety.
8-903.2 Residential occupancies.
8-903.2.1 Where toilet facilities are provided, alternative sewage disposal methods may be acceptable if approved by the local health department. In hotels, where private facilities are not provided, water closets at the ratio of one for each 15 rooms may be acceptable.
8-903.2.2 Toilet facilities are not required to be on the same floor or in the same building as sleeping rooms. Water-flush toilets may be located in a building immediately adjacent to the sleeping rooms. When alternative sewage disposal methods are utilized, they shall be located a minimum distance from the sleeping rooms or other locations as approved by the local health department.
8-903.2.3 Kitchen sinks shall be provided in all kitchens. The sink and countertop may be of any smooth nonabsorbent finish which can be maintained in a sanitary condition.
8-903.2.4 Hand washing facilities shall be provided for each dwelling unit and each hotel guest room. A basin and pitcher may be acceptable as adequate hand washing facilities.
8-903.2.5 Hot or cold running water is not required for each plumbing fixture, provided a sufficient amount of water is supplied to permit the fixture’s normal operation.
8-903.2.6 Bathtubs and lavatories with filler spouts less than 1 inch (25.4 mm) above the fixture rim may remain in use, provided there is an acceptable overflow below the rim.
8-903.2.7 Original or salvage water closets, urinals and flushometer valves shall be permitted in qualified historical buildings or properties. Historically accurate reproduction, nonlow-consumption water closets, urinals and flushometer valves shall be permitted except where historically accurate fixtures that comply with the regular code are available.
CHBC § 8-903.2 High relevance — show source text
8-903.2 Residential occupancies.
8-903.2.1 Where toilet facilities are provided, alternative sewage disposal methods may be acceptable if approved by the local health department. In hotels, where private facilities are not provided, water closets at the ratio of one for each 15 rooms may be acceptable.
8-903.2.2 Toilet facilities are not required to be on the same floor or in the same building as sleeping rooms. Water-flush toilets may be located in a building immediately adjacent to the sleeping rooms. When alternative sewage disposal methods are utilized, they shall be located a minimum distance from the sleeping rooms or other locations as approved by the local health department.
8-903.2.3 Kitchen sinks shall be provided in all kitchens. The sink and countertop may be of any smooth nonabsorbent finish which can be maintained in a sanitary condition.
8-903.2.4 Hand washing facilities shall be provided for each dwelling unit and each hotel guest room. A basin and pitcher may be acceptable as adequate hand washing facilities.
8-903.2.5 Hot or cold running water is not required for each plumbing fixture, provided a sufficient amount of water is supplied to permit the fixture’s normal operation.
8-903.2.6 Bathtubs and lavatories with filler spouts less than 1 inch (25.4 mm) above the fixture rim may remain in use, provided there is an acceptable overflow below the rim.
8-903.2.7 Original or salvage water closets, urinals and flushometer valves shall be permitted in qualified historical buildings or properties. Historically accurate reproduction, nonlow-consumption water closets, urinals and flushometer valves shall be permitted except where historically accurate fixtures that comply with the regular code are available.
8-903.3 Materials. New nonhistorical materials shall comply with the regular code requirements. The enforcing agency shall accept alternative materials which do not create a safety hazard where their use is necessary to maintain the historical integrity of the building.
8-903.4 Drainage and vent systems. Plumbing fixtures shall be connected to an adequate drainage and vent system. The enforcing agency may require operational tests for drainage and vent systems which do not comply with applicable requirements of the regular code. Vent terminations may be installed in any location which, in the opinion of the enforcing agency, does not create a safety hazard.
8-903.5 Indirect and special wastes. Indirect and special waste systems shall be installed so that no safety hazard is created. Chemical or industrial liquid wastes which may detrimentally affect the sanitary sewer system shall be pretreated to render them safe prior to discharge.
8-903.6 Traps and interceptors. Traps and interceptors shall comply with the regular code requirements except that the enforcing agency shall accept solutions which do not increase the safety hazard. Properly maintained “S” and drum traps may remain in use.
8-903.7 Joints and connections.
8-903.7.1 Joints and connections in new plumbing systems shall comply with applicable requirements of the regular code.
8-903.7.2 Joints and connections in existing or restored systems may be of any type that does not create a safety hazard.
8-903.8 Water distribution. Plumbing fixtures shall be connected to an adequate water distribution system. The enforcing agency may require operational tests for water distribution systems which do not comply with applicable requirements of the regular code. Prohibited (unlawful) connections and cross connections shall not be permitted.
CHBC § 710.11 High relevance — show source text
Where the preceding requirements are met and the vent, after leaving the sump, is combined with vents from fixtures discharging into the sump, the size of the combined vent need not exceed that required for the total number of fixtures discharging into the sump. No vent from an air-operating sewage ejector shall combine with other vents. 710.11 Air Tanks. Air tanks shall be so proportioned as to be of equal cubical capacity to the ejectors connected in addition to that in which there shall be maintained an air pressure of not less than 2 pounds per foot (lb/ft) (3 kg/m) of height the sewage is to be raised. No water-operated ejectors shall be permitted. 710.12 Grinder Pump Ejector. Grinder pumps shall be permitted to be used. 710.12.1 Discharge Piping. The discharge piping shall be sized in accordance with the manufacturer’s installation instructions and shall be not less than 1 [1] ⁄ 4 inches (32 mm) in diameter. A check valve and fullwaytype shutoff valve shall be located on the discharge line. 710.13 Macerating Toilet Systems and Pumped Waste Systems. Fixtures shall be permitted to discharge to a macerating toilet system, or pumped waste system shall be permitted as an alternate to a sewage pump system where approved by the Authority Having Jurisdiction. Such systems shall comply with ASME A112.3.4/CSA B45.9 and shall be installed in accordance with the manufacturer’s installation
instructions.
710.13.1 Sumps. The sump shall be watertight and gastight. 710.13.2 Discharge Piping. The discharge piping shall be sized in accordance with manufacturer’s instructions and shall be not less than [3] ⁄ 4 of an inch (20 mm) in diameter. The developed length of the discharge piping shall not exceed the manufacturer’s instructions. A check
174 2025 CALIFORNIA PLUMBING CODE
), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
SANITARY DRAINAGE
valve and fullway-type shutoff valve shall be located within the discharge line or internally within the device.
710.13.3 Venting. The plumbing fixtures that discharge into the macerating device shall be vented in accordance with this code. The sump shall be vented in accordance with the manufacturer’s instructions, and such vent shall be permitted to connect to the fixture venting.
711.0 Suds Relief.
711.1 General. Drainage connections shall not be made into a drainage piping system within 8 feet (2438 mm) of a vertical to horizontal change of direction of a stack containing suds-producing fixtures. Bathtubs, laundries, washing machine standpipes, kitchen sinks, and dishwashers shall be considered suds-producing fixtures. Where parallel vent stacks are required, they shall connect to the drainage stack at a point 8 feet (2438 mm) above the lowest point of the drainage stack.
Exceptions:
(1) Single-family residences.
(2) Stacks receiving the discharge from less than three stories of plumbing fixtures.
712.0 Testing.
CHBC § 0.9 High relevance — show source text
003)|Tension-controlled_3_|0.9|(e)|0.9|(f)| |1. For sections classified as transition, it shall be permitted to useφ corresponding to compression-controlled sections.
2. ε_t_
* is the greater of net tensile strain calculated for Pn = 0.1Agfc′_ and (ε_ty + 0.003).
3. For sections with factored axial compression force Pu ≥ 0.1Agfc′,φ shall be calculated using equation (c) or (d) for sections classified as transition, as applicable.|1. For sections classified as transition, it shall be permitted to useφ corresponding to compression-controlled sections.
2. ε_t_
* is the greater of net tensile strain calculated for Pn = 0.1Agfc′_ and (ε_ty + 0.003).
3. For sections with factored axial compression force Pu ≥ 0.1Agfc′,φ shall be calculated using equation (c) or (d) for sections classified as transition, as applicable.|1. For sections classified as transition, it shall be permitted to useφ corresponding to compression-controlled sections.
2. ε_t_
* is the greater of net tensile strain calculated for Pn = 0.1Agfc′_ and (ε_ty + 0.003).
3. For sections with factored axial compression force Pu ≥ 0.1Agfc′,φ shall be calculated using equation (c) or (d) for sections classified as transition, as applicable.|1. For sections classified as transition, it shall be permitted to useφ corresponding to compression-controlled sections.
2. ε_t_
* is the greater of net tensile strain calculated for Pn = 0.1Agfc′_ and (ε_ty + 0.003).
3. For sections with factored axial compression force Pu ≥ 0.1Agfc′,φ shall be calculated using equation (c) or (d) for sections classified as transition, as applicable.|1. For sections classified as transition, it shall be permitted to useφ corresponding to compression-controlled sections.
2. ε_t_
* is the greater of net tensile strain calculated for Pn = 0.1Agfc′_ and (ε_ty + 0.003).
3. For sections with factored axial compression force Pu ≥ 0.1Agfc′,φ shall be calculated using equation (c) or (d) for sections classified as transition, as applicable.|1. For sections classified as transition, it shall be permitted to useφ corresponding to compression-controlled sections.
2. ε_t_
* is the greater of net tensile strain calculated for Pn = 0.1Agfc′_ and (ε_ty + 0.003).
3. For sections with factored axial compression force Pu ≥ 0.1Agfc′,φ shall be calculated using equation (c) or (d) for sections classified as transition, as applicable.|1909A.1.12 ACI 318, Section 24.2.1. Add Section 24.2.1.1 to ACI 318 as follows:
CHBC § 8-902.5 Medium relevance — show source text
8-902.5 Combustion air.
8-902.5.1 All fuel-burning appliances and equipment shall be provided a sufficient supply of air for proper fuel combustion, ventilation and draft hood dilution.
8-902.5.2 The enforcing agency may require operational tests for combustion air systems which do not comply with applicable requirements of the regular code.
8-902.6 Venting of appliances.
8-902.6.1 Every appliance required to be vented shall be connected to an approved venting system. Venting systems shall develop a positive flow adequate to convey all combustion products to the outside atmosphere.
8-902.6.2 Masonry chimneys in structurally sound condition may remain in use for all fuel-burning appliances, provided the flue is evaluated and documentation provided that the masonry and grout are in good condition. Terra cotta chimneys and Type C metallic vents installed in concealed spaces shall not remain in use unless otherwise mitigated and approved on a case-by-case basis.
8-902.6.3 The enforcing agency may require operational tests for venting systems which do not comply with applicable requirements of the regular code.
8-902.7 Ducts.
8-902.7.1 New ducts shall be constructed and installed in accordance with applicable requirements of the regular code.
8-902.7.2 Existing duct systems which do not comply with applicable requirements of the regular code and do not, in the opinion of the enforcing agency, constitute a safety or health hazard may remain in use.
8-902.8 Ventilating systems.
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MECHANICAL, PLUMBING AND ELECTRICAL REQUIREMENTS
8-902.8.1 Ventilating systems shall be installed so that no safety hazard is created.
8-902.8.2 Grease hoods and grease hood exhaust systems shall be furnished and installed in accordance with applicable requirements of the regular code. Existing systems which are altered shall comply with the regular code.
8-902.9 Miscellaneous equipment requirements.
8-902.9.1 The following appliances and equipment shall be installed so that no safety hazard is created: warm air furnaces, space heating equipment, vented decorative appliances, floor furnaces, vented wall furnaces, unit heaters, room heaters, absorption units, refrigeration equipment, duct furnaces, infrared radiant heaters, domestic incinerators, miscellaneous heat-producing appliances and water heaters.
8-902.9.2 Storage-type water heaters shall be equipped with a temperature- and pressure-relief valve in accordance with applicable requirements of the regular code.
SECTION 8-903 — PLUMBING
8-903.1 General. Plumbing systems shall comply with the regular code unless otherwise noted.
8-903.1.1 The provisions of the CHBC shall apply to the acceptance, location, installation, alteration, repair, relocation, replacement or addition of any plumbing system or equipment within or attached to a historical building.
8-903.1.2 Existing systems which do not, in the opinion of the enforcing agency, constitute a safety hazard may remain in use.
8-903.1.3 The enforcing agency may approve any alternative to these regulations which achieves reasonably equivalent life safety.
8-903.2 Residential occupancies.
CHBC § 8-903.3 Medium relevance — show source text
8-903.3 Materials. New nonhistorical materials shall comply with the regular code requirements. The enforcing agency shall accept alternative materials which do not create a safety hazard where their use is necessary to maintain the historical integrity of the building.
8-903.4 Drainage and vent systems. Plumbing fixtures shall be connected to an adequate drainage and vent system. The enforcing agency may require operational tests for drainage and vent systems which do not comply with applicable requirements of the regular code. Vent terminations may be installed in any location which, in the opinion of the enforcing agency, does not create a safety hazard.
8-903.5 Indirect and special wastes. Indirect and special waste systems shall be installed so that no safety hazard is created. Chemical or industrial liquid wastes which may detrimentally affect the sanitary sewer system shall be pretreated to render them safe prior to discharge.
8-903.6 Traps and interceptors. Traps and interceptors shall comply with the regular code requirements except that the enforcing agency shall accept solutions which do not increase the safety hazard. Properly maintained “S” and drum traps may remain in use.
8-903.7 Joints and connections.
8-903.7.1 Joints and connections in new plumbing systems shall comply with applicable requirements of the regular code.
8-903.7.2 Joints and connections in existing or restored systems may be of any type that does not create a safety hazard.
8-903.8 Water distribution. Plumbing fixtures shall be connected to an adequate water distribution system. The enforcing agency may require operational tests for water distribution systems which do not comply with applicable requirements of the regular code. Prohibited (unlawful) connections and cross connections shall not be permitted.
8-903.9 Building sewers and private sewage disposal systems. New building sewers and new private sewage disposal systems shall comply with applicable requirements of the regular code.
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MECHANICAL, PLUMBING AND ELECTRICAL REQUIREMENTS
8-903.10 Fuel-gas piping. Fuel-gas piping shall comply with the regular code requirements except that the enforcing agency shall accept solutions which do not increase the safety hazard.
SECTION 8-904 — ELECTRICAL
8-904.1 General. Electrical systems shall comply with the regular code unless otherwise permitted by this code, or approved by the authority having jurisdiction.
8-904.1.1 The provisions of the CHBC shall apply to the acceptance, location, installation, alteration, repair, relocation, replacement or addition of any electrical system or portion thereof, the premise wiring, or equipment fixed in place as related to restoration within or attached to a qualified historical building or property.
8-904.1.2 Existing systems, wiring methods and electrical equipment which do not, in the opinion of the enforcing agency, constitute a safety hazard may remain in use.
8-904.1.3 The enforcing agency may approve any alternative to the CHBC which achieves equivalent safety.
8-904.1.4 Archaic methods that do not appear in present codes may remain and may be extended if, in the opinion of the enforcing agency, they constitute a safe installation.
8-904.2 Wiring methods.
CHBC § 323-9843 Medium relevance — show source text
State Librarian [SL]
library.ca.gov csllaw@library.ca.gov (916) 323-9843 Public Library Construction & Renovation
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HOW TO DETERMINE WHERE CHANGES HAVE BEEN MADE
Symbols in the margins indicate where changes have been made or language has been deleted.
This symbol indicates that a change has been made.
- This symbol indicates deletion of language.
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PART 8 CONTAINS ALTERNATIVE REGULATIONS
FOR QUALIFIED HISTORICAL BUILDINGS
The California Historical Building Code (CHBC) is unique among state regulations. The authoring of the original CHBC required state agencies promulgating regulations for building construction to work in harmony with representatives of other design and construction disciplines. The result was a totally new approach to building codes for historical structures, which maintains currently acceptable life safety standards. These regulations are also unique in that they are performance oriented rather than prescriptive. The provisions of the CHBC are to be applied by the enforcing authority of every city, county, city and county, or state agency in permitting repairs, alterations and additions necessary for the preservation, rehabilitation, relocation, related construction, change of use or continued use of a qualified historical building. The authority for use of the CHBC is vested in Sections 18950 through 18961 of the Health and Safety Code. Section 18954 states, “The building department of every city or county or other local agency that has jurisdiction over the enforcement of code within its legal authority shall apply the alternative standards and regulations adopted pursuant to Section 18959.5 in permitting repairs, alterations, and additions necessary for the preservation, restoration, rehabilitation, safety, moving, or continued use of a qualified historical building or structure. A state agency shall apply the alternative regulations adopted pursuant to Section 18959.5 in permitting repairs, alterations, and additions necessary for the preservation, restoration, rehabilitation, safety, moving, or continued use of a qualified historical building or structure.” However, be aware that in order to use the CHBC, the structure under consideration must be qualified by being designated as an historical building or structure. Section 18955 states, “For the purposes of this part, a qualified historical building or structure is any structure or property, collection of structures, and their related sites deemed of importance to the history, architecture, or culture of an area by an appropriate local or state governmental jurisdiction. This shall include historical buildings or structures on existing or future national, state or local historical registers or official inventories, such as the National Register of Historic Places, State Historical Landmarks, State Points of Historical Interest, and city or county registers or inventories of historical or architecturally significant sites, places, historic districts, or landmarks. This shall also include places, locations, or sites identified on these historical registers or official inventories and deemed of importance to the history, architecture, or culture of an area by an appropriate local or state governmental jurisdiction.” The regulations of the CHBC have the same authority as state law and are to be considered as such. Liability is the same as for prevailing law. The intent of the CHBC is to save California’s architectural heritage by recognizing the unique construction problems inherent in historical buildings and by providing a code to deal with these problems.
CHBC § 1.8.7.3 Medium relevance — show source text
3. The local building department may require tests performed by an approved testing agency at the expense of the owner or owner’s agent as proof of compliance.
4. If the proposed alternate is related to accessi bil- ity in covered multifamily dwellings or facilities serving covered multifamily dwellings, as defined in Chapter 2 of the California Building Code, the proposed alternate must also meet the threshold set for equivalent facilitation as defined in Chapter 2 of the California Building Code.
For additional information regarding approval of alternates by a local building department pur- suant to the State Housing Law, see California Health and Safety Code Section 17951(e) and Cali- fornia Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1.
1.8.7.3 Department of Housing and Community Devel- opment. The Department of Housing and Community Development may approve alternates for use in the erec- tion, construction, reconstruction, movement, enlarge- ment, conversion, alteration, repair, removal, or demolition of apartments, condominiums, hotels, motels, lodging houses, dwellings, or accessory structures thereto, and permanent buildings in mobilehome parks and special occupancy parks. The consideration and approval of alternates shall comply with the following:
1. The department may require tests at the expense of the owner or owner’s agent to substantiate compli- ance with the California Building Standards Code.
2. The approved alternate shall, for its intended pur- pose, be at least equivalent in performance and safety to the materials, designs, tests, or methods of construction prescribed by this code.
1.8.8 Appeals Board.
1.8.8.1 General. Every city, county, or city and county shall establish a process to hear and decide appeals of orders, decisions, and determinations made by the enforc- ing agency relative to the application and interpretation of this code and other regulations governing construction use, maintenance and change of occupancy. The govern- ing body of any city, county, or city and county may estab- lish a local appeals board and a housing appeals board to serve this purpose. Members of the appeals board(s) shall not be employees of the enforcing agency and shall be knowledgeable in the applicable building codes, reg- ulations and ordinances as determined by the governing body of the city, county, or city and county.
Where no such appeals boards or agencies have been established, the governing body of the city, county, or city and county shall serve as the local appeals board or housing appeals board as specified in California Health and Safety Code Sections 17920.5 and 17920.6.
1.8.8.2 Definitions. The following terms shall for the purposes of this section have the meaning shown.
CHBC § 8-9 Medium relevance — show source text
Bolt spacing shall not
exceed 6 feet (1830 mm) on center and shall not be less than 12 inches (305 mm) on center.
6. Other masonry based on tests or other substantiated data.
7. Embedded bolts to be tested as specified in regular code standards.
8. Stresses given may be increased for combinations of loads as specified in the regular code.
9. Adhesives shall be approved by the enforcing agency and installed in accordance with the manufacturer’s recommendations. All drilling dust shall be removed from drilled
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8-9 MECHANICAL, PLUMBING AND ELECTRICAL REQUIREMENTS
SECTION 8-901 — PURPOSE, INTENT AND SCOPE
8-901.1 Purpose. The purpose of the CHBC is to provide regulations for the mechanical, plumbing and electrical systems of buildings designated as qualified historical buildings or properties. The CHBC requires enforcing agencies to accept any reasonable equivalent solutions to the regular code when dealing with qualified historical buildings or properties.
8-901.2 Intent. The intent of the CHBC is to preserve the integrity of qualified historical buildings or properties while providing a reasonable level of protection from fire, health and life safety hazards (hereinafter referred to as safety hazards) for the building occupants.
8-901.3 Scope. The CHBC shall be applied in conjunction with the regular code whenever compliance with the regular code is required for qualified historical buildings or properties.
8-901.4 Safety hazard. No person shall permit any safety hazard to exist on premises under their control, or fail to take immediate action to abate such hazard. Existing systems which constitute a safety hazard when operational may remain in place, provided they are completely and permanently rendered inoperative. Safety hazards created by inoperative systems shall not be permitted to exist. Requirements of the regular code concerning general regulations shall be complied with, except that the enforcing agency shall accept solutions which do not cause a safety hazard.
8-901.5 Energy conservation. Qualified historical buildings or properties covered by this part are exempted from compliance with energy conservation standards. When new nonhistorical lighting and space conditioning system components, devices, appliances and equipment are installed, they shall comply with the requirements of Title 24, Part 6, The California Energy Code, except where the historical significance or character-defining features are threatened.
SECTION 8-902 — MECHANICAL
8-902.1 General. Mechanical systems shall comply with the regular code unless otherwise modified by this chapter.
8-902.1.1 The provisions of the CHBC shall apply to the acceptance, location, installation, alteration, repair, relocation, replacement or addition of any heating, ventilating, air conditioning, domestic incinerators, kilns or miscellaneous heat-producing appliances or equipment within or attached to a historical building.
8-902.1.2 Existing systems which do not, in the opinion of the enforcing agency, constitute a safety hazard may remain in use.
8-902.1.3 The enforcing agency may approve any alternative to the CHBC which would achieve equivalent life safety.
8-902.2 Heating facilities. All dwelling-type occupancies covered under this chapter shall be provided with heating facilities. Woodburning or pellet stoves or fireplaces may be acceptable as heating facilities.
CHBC § 8-1002.1 Medium relevance — show source text
8-1002.1 The CHBC shall apply to all sites and districts and their features associated with qualified historical buildings or qualified historical districts as outlined in 8-1001.2 Scope.
8-1002.2 Where the application of regular code may impact the associated features of qualified historical properties beyond their footprints, by work performed secondarily, those impacts shall also be covered by the CHBC.
8-1002.3 This chapter shall be applied for all issues regarding code compliance or other standard or regulation as they affect the purpose of this chapter.
8-1002.4 The application of any code or building standard shall not unduly restrict the use of a qualified historical building or property that is otherwise permitted pursuant to Chapter 8-3 and the intent of the State Historical Building Code, Section 18956.
SECTION 8-1003 — SITE RELATIONS
The relationship between a building or property and its site, or the associated features of a district (including qualified historical landscape), site, objects and their features are critical components that may be one of the criteria for these buildings and properties to be qualified under the CHBC. The CHBC recognizes the importance of these relationships. This chapter shall be used to provide context sensitive solutions for treatment of qualified historical buildings, properties, district or their associated historical features, or when work to be performed secondarily impacts the associated historical features of a qualified historical building or property.
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APPENDIX A Col2 Col3 Col4 CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY CHAPTER 8-6—TABLE 1—PROVISION APPLICABILITY Title II
Public EntitiesTitle III
Private EntitiesTitle III
Barrier RemovalSECTION 8-601 PURPOSE, INTENT, SCOPE
**8-601.1 Purpose.**The purpose of the CHBC is to provide alternative regulations to facilitate
access and use by persons with disabilities to and throughout facilities designated as quali-
fied historical buildings or properties. These regulations require enforcing agencies to
accept alternatives to regular code when dealing with qualified historical buildings or
properties.
**8-601.2 Intent.**The intent of this chapter is to preserve the integrity of qualified historical
buildings and properties while providing access to and use by persons with disabilities.
**8-601.3 Scope.**The CHBC shall apply to every qualified historical building or property that
is required to provide access to persons with disabilities.
1.Provisions of this chapter do not apply to new construction or reconstruction/replicas of
historical buildings.
2. Where provisions of this chapter apply to alteration of qualified historical buildings or
properties, alteration is defined in_ California Building Code_ (CBC), Chapter 2.
**8-601.4 General application.CHBC § 208.0 Medium relevance — show source text
Existing Work. A plumbing system or any part thereof that has been installed prior to the effective date of this code.
Expansion Joint. A fitting or arrangement of pipe and fittings that permit the contraction and expansion of a piping system.
Expansion Tank. A vessel used to protect potable water systems from excessive pressure.
208.0 – F –
F Rating. The time period that the penetration firestop system limits the spread of fire through the penetration, where tested in accordance with ASTM E814 or UL 1479.
Fixture Branch. A water supply pipe between the fixture supply pipe and the water distribution pipe.
Fixture Drain. The drain from the trap of a fixture to the junction of that drain with any other drainpipe.
Fixture Fitting. A device that controls and guides the flow of water.
Fixture Supply. A water supply pipe is connecting the fixture with the fixture branch.
Fixture Unit. A quantity in terms of which the load-producing effects on the plumbing system of different kinds of plumbing fixtures are expressed on some arbitrarily chosen scale.
Flammable Vapor or Fumes. The concentration of flammable constituents in the air that exceeds 25 percent of its lower flammability limit (LFL).
Flood Hazard Area. The greater of the following two areas:
(1) The area within a floodplain subject to a 1 percent or greater chance of flooding in any given year.
(2) The area designated as a flood hazard area on a community’s flood hazard map, or otherwise legally designated.
Flood Level. See Flooded.
Flood-Level Rim. The top edge of a receptor or fixture from which water overflows.
Flooded. A fixture is flooded where the liquid therein rises to the flood-level rim.
Flue Collar. That portion of an appliance designed for the attachment of a draft hood, vent connector, or venting system. [NFPA 54:3.3.44]
Flush Tank. A tank located above or integral with water closets, urinals, or similar fixtures for the purpose of flushing the usable portion of the fixture.
Flush Valve. A valve located at the bottom of a tank for flushing water closets and similar fixtures.
Flushometer Tank. A tank integrated within an air accumulator vessel that is designed to discharge a predetermined quantity of water to fixtures for flushing purposes.
Flushometer Valve. A valve that discharges a predetermined quantity of water to fixtures for flushing purposes and is actuated by direct water pressure.
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DEFINITIONS
FOG Disposal System. A grease interceptor that reduces nonpetroleum fats, oils, and grease (FOG) in the effluent by separation, mass, and volume reduction.
Food Establishment . [DPH] Any room, building, place or portion thereof, maintained, used or operated for purpose of storing, preparing, serving, packaging, transporting, sal- vaging or otherwise handling food at the retail level.
Fuel Gas. Natural, manufactured liquefied petroleum, or a mixture of these.
209.0 – G –
Gang or Group Shower. Two or more showers in a com mon area.
CHBC § 1009.1 Medium relevance — show source text
TABLE 1009.1 APPROVED INTERCEPTORS (CLARIFIERS)
APPLICATION STANDARD
Fats, Oil, Grease
(FOG)ASME A112.14.3, ASME A112.14.4,
ASME A112.14.6, CSA B481,
ANSI/CAN/IAPMO Z1001,
PDI G-101, PDI G-102Solid Waste IAPMO IGC 167
Non-petroleum OilASME A112.14.6, IAPMO PS 80,
PDI G-102
Petroleum OilASTM D6104, IAPMO IGC 183,
IAPMO IGC 3251009.2 Approval. The size, type, and location of each interceptor (clarifier) or separator shall be approved by the Authority Having Jurisdiction. Except where otherwise specifically permitted, no wastes other than those requiring treatment or separation shall be discharged into an interceptor (clarifier). 1009.3 Design. Interceptors (clarifiers) for sand and similar heavy solids shall be so designed and located as to be readily accessible for cleaning and shall have a water seal of not less than 6 inches (152 mm). 1009.4 Relief Vent. Interceptors (clarifiers) shall be so designed that they will not become air-bound where closed covers are used. Each interceptor (clarifier) shall be properly vented.
1009.5 Location. Each interceptor (clarifier) cover shall be readily accessible for servicing and maintaining the interceptor (clarifier) in working and operating condition. The use of ladders or the removal of bulky equipment to service interceptors (clarifiers) shall constitute a violation of accessibility. Location of interceptors (clarifiers) shall be shown on the approved building plan. 1009.6 Maintenance of Interceptors. Interceptors shall be maintained in efficient operating condition by periodic removal of accumulated grease, scum, oil, or other floating substances and solids deposited in the interceptor. 1009.7 Discharge. The waste pipe from oil and sand interceptors shall discharge as approved by the Authority Having Jurisdiction.
1010.0 Slaughterhouses, Packing Establishments, etc.
1010.1 General. A fish, fowl, and animal slaughterhouse or establishment; a fish, fowl, and meat packing or curing establishment; a soap factory, tallow-rendering, fat-rendering, and a hide-curing establishment shall be connected to and shall drain or discharge into an approved grease interceptor (clarifier).
TABLE 1009.1 APPROVED INTERCEPTORS (CLARIFIERS)
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TRAPS AND INTERCEPTORS
1010.2 Meat and Poultry Processing Plants. [AGR]
1010.2.1 Drainage and Plumbing Systems. Drainage and plumbing systems shall meet the require- ments of Section 724.0.
1010.2.1.1 Each floor drain shall be equipped with a deep-seal trap.
Frequently asked questions
Can I install a historic toilet in any old building?
No. The CHBC allowances for historic fixtures apply only to qualified historical buildings or properties; verify the building’s qualification before applying CHBC provisions.
Are high‑water‑use historic fixtures banned under the CHBC?
No. Nonlow‑consumption historically accurate reproductions or originals are permitted under § 8-903.2.7, except where a historically accurate fixture that complies with the regular code is available.
What happens if a historic fixture creates a plumbing hazard?
If the enforcing agency determines a safety hazard, the fixture or system may not be allowed to remain; remediation or replacement can be required despite historic value (§ 8-903.1.2).
Do I need to prove historic accuracy or performance?
Be prepared to document historic authenticity and, if requested, run operational tests of drainage, venting, or water distribution; the agency can require testing or reasonable alternatives (§ 8-903.1.3, § 8-903.4).
Is a flushometer valve defined anywhere?
Yes — the Plumbing Code defines a flushometer valve as a valve that discharges a predetermined quantity of water to fixtures and is actuated by direct water pressure. Consult the Plumbing Code for technical definitions.
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