CHBC · California Historical Building Code
Drainage, vent terminations, traps and interceptors
In a historic building the CHBC requires that plumbing be connected to an adequate drainage and vent system, that chemical wastes be pretreated if they could harm sewers, and that traps/interceptors follow regular plumbing rules unless the enforcing agency accepts safe historic alternatives (S/drum traps can remain if maintained).
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
Plumbing fixtures in a qualified historical building must be connected to an adequate drainage and vent system and vents must be terminated where they do not create a safety hazard (§ 8-903.4). Indirect/special wastes that could harm the public sewer must be pretreated before discharge (§ 8-903.5). Traps and interceptors must meet the regular plumbing code, but the enforcing agency may accept alternative solutions (and may allow properly maintained “S” and drum traps to remain) as long as no increased safety hazard results (§ 8-903.6) .
The single most important rule: all historic plumbing arrangements must be kept or adapted so they do not create a safety hazard — the CHBC lets the enforcing agency accept historic or alternative solutions when they are equally safe (see § 8-903.4, § 8-903.5, § 8-903.6) .
Requirements in detail
Core mandates (plain-language)
- Connect every plumbing fixture to an adequate drainage and vent system. The CHBC defers technical sizing and construction details to the regular plumbing code but makes the adequacy and safety the controlling concern (§ 8-903.4) .
- The enforcing agency may require operational tests when a drainage or vent system does not meet the regular code (§ 8-903.4) .
- Indirect and special waste systems must be installed so they do not create a safety hazard; chemical or industrial liquid wastes that could harm the sanitary sewer must be pretreated before discharge (§ 8-903.5) .
- Traps and interceptors are required to comply with the regular code, except that the enforcing agency may accept historic solutions that do not increase the safety hazard. Properly maintained “S” traps and drum traps may be left in use under the CHBC (§ 8-903.6) .
Decision table — what to check, and the relevant CHBC reference
| Decision / dimension | What matters for the historical building | Code Reference |
|---|---|---|
| Is the fixture connected to a functioning drainage and vent system? | The system must be adequate; if not, the enforcing agency can require tests or corrective action to prevent a safety hazard. | § 8-903.4 |
| Where can vent terminations be located? | Anywhere the enforcing agency judges will not create a safety hazard (location is discretionary). | § 8-903.4 |
| Chemical/industrial waste discharge | Must be pretreated if it could detrimentally affect the sanitary sewer. | § 8-903.5 |
| Traps and interceptors sizing/installation | Must comply with the regular plumbing code; however, the enforcing agency may accept alternative/historic solutions that do not increase hazards. S and drum traps may remain if properly maintained. | § 8-903.6 |
| When can the enforcing agency accept nonstandard materials or methods? | When the alternative does not create a safety hazard; the agency may approve alternatives that achieve equivalent safety. | § 8-903.1, § 8-903.3, § 8-903.6 |
What the CHBC does not specify (and what that means)
- The CHBC intentionally defers technical sizing and installation details (for example, trap arm lengths, interceptor capacities, or trap seal depths) to the regular California Plumbing Code. The CHBC requirement is safety/adequacy and local enforcing-agency approval — it does not set the numeric sizing rules itself (§ 8-903.4, § 8-903.6) .
- Therefore, when a numeric or construction detail is needed, consult the applicable regular plumbing code and the enforcing agency for the historically-appropriate solution.
Exceptions & special cases
- The CHBC explicitly lets the enforcing agency accept alternative methods, materials, or historic devices so long as they do not increase a safety hazard (applies across drainage, vents, traps and interceptors) — e.g., retaining original fixtures, archaic materials, or nonstandard vent terminations when safe (§ 8-903.1, § 8-903.3, § 8-903.6) .
- Vent terminations: the CHBC allows vent terminations to be located in any place that the enforcing agency finds safe — this grants latitude for historic rooflines, parapets, or other character-defining roof features (§ 8-903.4) .
- Existing S and drum traps: these archaic trap types are not automatically prohibited; if they are properly maintained and the enforcing agency judges them not to create a hazard, they may remain in service (§ 8-903.6) .
- Operational tests: the enforcing agency may request tests (e.g., water/air tests) for drainage, vent or combustion systems that don’t meet the regular code to verify safety and performance (§ 8-903.4) .
Common mistakes
- Assuming the CHBC gives numeric sizing rules. It does not — it defers to the regular plumbing code for sizing; CHBC controls safety acceptance and agency discretion (§ 8-903.4, § 8-903.6) .
- Removing or replacing historic S traps or drum traps without consulting the enforcing agency. Properly maintained historic traps may be allowed to remain under § 8-903.6 .
- Placing vent terminations solely for aesthetics without getting agency concurrence; the CHBC requires that vent terminations be located where they do not create a safety hazard — the enforcing agency has the final say (§ 8-903.4) .
- Forgetting pretreatment for hazardous chemical or industrial wastes — CHBC requires pretreatment when discharge could harm the sewer system (§ 8-903.5) .
- Not budgeting for possible operational testing: the enforcing agency may require tests for noncompliant systems to prove safety and functionality (§ 8-903.4) .
Worked example — historic cafe adding a dishwasher (concrete scenario)
Scenario: A qualified historic café (existing plumbing) wants to install a new commercial dishwasher that will discharge greasy wastewater and a small sanitizer chemical rinse.
- CHBC trigger: The dishwasher discharge is a plumbing change inside a qualified historical building; the installation must not create a safety hazard and must connect to an adequate drainage and vent system (§ 8-903.4) .
- Grease control: Because the dishwasher produces grease, a grease interceptor is required by the regular plumbing code. The CHBC requires compliance with the regular code for traps and interceptors, but allows the enforcing agency to accept alternative historic-friendly solutions that do not increase hazard (§ 8-903.6) .
- Chemical pretreatment: The sanitizer chemical (if it could detrimentally affect the sewer) must be pretreated or managed per § 8-903.5; the CHBC requires pretreatment where wastes could damage the sanitary sewer (§ 8-903.5) .
- Practical steps and numbers (example, not a code mandate): assume the dishwasher has a rated discharge of 2.5 gpm and the sink used for pre-rinse is 3.0 gpm; the combined anticipated peak flow is 5.5 gpm. The CHBC does not specify interceptor capacity numerically — you must size the grease interceptor per the regular California Plumbing Code (or local plumbing ordinance) for that flow and load. The CHBC requirement is that the installed interceptor and pretreatment scheme not create a safety hazard, and the enforcing agency may require an operational test if the solution departs from regular-code practice (§ 8-903.4, § 8-903.6) .
- Outcome under CHBC: Submit the proposal and sizing method (based on the regular plumbing code) to the enforcing agency; if the agency determines the proposed interceptor and pretreatment will not create a safety hazard, it may approve the installation even if some historic compromises are made. If an unconventional historic-preservation-friendly device is proposed, document its performance and be prepared for an operational test per § 8-903.4 .
Important note: the CHBC prescribes the acceptance standard (safety/adequacy) and agency discretion — for the actual numeric sizing and installation details you must use the regular plumbing code; the CHBC text does not provide those numeric tables or formulas (§ 8-903.6) .
Related provisions
- § 8-903.1 — General CHBC plumbing acceptance and scope (CHBC applies to acceptance, location, installation, alteration, repair, replacement, etc.)
- § 8-903.3 — Materials: new nonhistorical materials must comply with the regular code; agency may accept alternatives that don’t create hazards
- § 8-903.7 — Joints and connections: new systems must comply with regular code; existing or restored systems may use any type that does not create a hazard
- § 8-902.6 — Venting of appliances: required venting and operational tests for venting systems (useful when plumbing ties to vented combustion appliances)
Code references
Grounded in the retrieved California Historical Building Code — click a citation to read the verbatim passage:
CHBC § 8-903.3 High 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 § 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 § 8-1 High relevance — show source text
CHAPTER 8 INTERIOR FINISHES. . . . . . . . . . . . . . . . . . . . . .8-1
801 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
802 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
803 Wall and Ceiling Finishes . . . . . . . . . . . . . . . . . . . . . . . . 8-3
804 Interior Floor Finish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
805 Combustible Materials in Types I and II Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-7
806 Decorative Materials and Trim . . . . . . . . . . . . . . . . . . . 8-7
807 Insulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-8
808 Acoustical Ceiling Systems . . . . . . . . . . . . . . . . . . . . . . 8-8
CHAPTER 9 FIRE PROTECTION AND LIFE
SAFETY SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-1
901 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-7
902 Fire Pump and Riser Room Size . . . . . . . . . . . . . . . . . . 9-7
903 Automatic Sprinkler Systems . . . . . . . . . . . . . . . . . . . . 9-8
904 Alternative Automatic Fire-Extinguishing Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-17
905 Standpipe Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-20
906 Portable Fire Extinguishers . . . . . . . . . . . . . . . . . . . . . 9-22
907 Fire Alarm and Detection Systems . . . . . . . . . . . . . . . 9-25
908 Emergency Alarm Systems . . . . . . . . . . . . . . . . . . . . . 9-43
909 Smoke Control Systems . . . . . . . . . . . . . . . . . . . . . . . . 9-43
910 Smoke and Heat Removal . . . . . . . . . . . . . . . . . . . . . . 9-51
CHBC § 8-8 Medium relevance — show source text
CHAPTER 8-8 ARCHAIC MATERIALS AND METHODS OF
CONSTRUCTION . . . . . . . . . . . . . . . . . . . . . . . 15
Section
8-801 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . 15 8-802 General Engineering Approaches. . . . . . . . . . . . . . . . . 15 8-803 Nonstructural Archaic Materials. . . . . . . . . . . . . . . . . . 15
8-804 Allowable Conditions for Specific Materials . . . . . . . 15 8-805 Masonry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 8-806 Adobe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
8-807 Wood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
8-808 Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
8-809 Steel and Iron . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
8-810 Hollow Clay Tile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
8-811 Veneers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
8-812 Glass and Glazing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
CHAPTER 8-9 MECHANICAL, PLUMBING AND ELECTRICAL REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . 19
Section
8-901 Purpose, Intent and Scope . . . . . . . . . . . . . . . . . . . . . . 19 8-902 Mechanical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
8-903 Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 8-904 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
CHAPTER 8-10 QUALIFIED HISTORICAL DISTRICTS,
SITES AND OPEN SPACES . . . . . . . . . . . . . . . 23
Section
CHBC § 8-5 Medium relevance — show source text
803 Fire Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
804 Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
805 Structural. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9
806 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10
807 Mechanical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10
808 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10
809 Energy Conservation. . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10
CHAPTER 9 ALTERATIONS—LEVEL 3 . . . . . . . . . . . . . . . . . .9-3
901 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
902 Special Use and Occupancy. . . . . . . . . . . . . . . . . . . . . . 9-3
903 Building Elements and Materials . . . . . . . . . . . . . . . . . 9-3
904 Fire Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4
905 Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4
906 Structural. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4
907 Energy Conservation. . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4
908 Emergency Responder Communications Enhancement System Coverage. . . . . . . . . . . . . . . . 9-5
CHAPTER 10 CHANGE OF OCCUPANCY . . . . . . . . . . . . . . .10-3
1001 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3
1002 Special Use and Occupancy. . . . . . . . . . . . . . . . . . . . . 10-3
1003 Building Elements and Materials . . . . . . . . . . . . . . . . 10-3
CHBC § 8-902.8.1 Medium 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 § 8-1001.1 Medium relevance — show source text
8-1001.1 Purpose. The purpose of this chapter is to provide regulations for the preservation, rehabilitation, restoration and reconstruction of associated historical features of qualified historical buildings, properties or districts (as defined in Chapter 8-2), and for which Chapters 8-3 through 8-9 of the CHBC may not apply.
8-1001.2 Scope. This chapter applies to the associated historical features of qualified historical buildings or properties such as historical districts that are beyond the buildings themselves which include, but are not limited to, natural features and designed site and landscape plans with natural and man-made landscape elements that support their function and aesthetics. This may include, but will not be limited to:
- Site plan layout configurations and relationships (pedestrian, equestrian and vehicular site circulation, topographical grades and drainage, and use areas).
- Landscape elements (plant materials, site structures other than the qualified historical building, bridges and their associated structures, lighting, water features, art ornamentation, and pedestrian, equestrian and vehicular surfaces).
- Functional elements (utility placement, erosion control and environmental mitigation measures).
SECTION 8-1002 — APPLICATION
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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CHBC § 3108.12.1 Medium relevance — show source text
3108.12.1 Installation. Heating or cooking equipment, tanks, piping, hoses, fittings, valves, tubing and other related components shall be installed as specified in the International Fuel Gas Code and the California Mechanical Code, and shall be approved by the fire code official.
3108.12.2 Venting. Gas, liquid and solid fuel-burning equipment designed to be vented shall be vented to the outside air as specified in the International Fuel Gas Code and the California Mechanical Code . Such vents shall be equipped with approved spark arresters where required. Where vents or flues are used, all portions of the tent or membrane structure shall be not less than 12 inches (305 mm) from the flue or vent.
3108.12.3 Location. Cooking and heating equipment shall not be located within 10 feet (3048 mm) of exits or combustible materials.
3108.13 Flammable and combustible liquids. The storage of flammable and combustible liquids and the use of flammable-liquidfueled equipment shall be in accordance with Sections 3108.13.1 through 3108.13.3.
3108.13.1 Use. Flammable-liquid-fueled equipment shall not be used in tents or membrane structures.
3108.13.2 Flammable and combustible liquid storage. Flammable and combustible liquids shall be stored outside in an approved manner not less than 50 feet (15 240 mm) from tents or membrane structures. Storage shall be in accordance with Chapter 57.
[California Code of Regulations, Title 19, Division 1, §324.(a) and (b)] Flammable and Combustible Liquids.
(a) Liquids having a flash point below 200°F shall not be stored in any tent nor less than 50 feet from any tent.
(b) Flammable or combustible liquids shall be stored and dispensed in accordance with the provisions of the California Fire Code. The enforcing authority may permit limited quantities of flammable or combustible liquids required for display and normal merchandising.
3108.13.3 Refueling. Refueling shall be performed in an approved location not less than 20 feet (6096 mm) from tents or membrane structures.
3108.14 Display of motor vehicles. Liquid- and gas-fueled vehicles and equipment used for display within tents or membrane structures shall be in accordance with Sections 3108.14.1 through 3108.14.5.3.
3108.14.1 Batteries. Batteries shall be disconnected except where the fire code official requires that the batteries remain connected to maintain safety features.
3108.14.2 Fuel. Vehicles or equipment shall not be fueled or defueled within the tent or membrane structure.
3108.14.2.1 Quantity limit. Fuel in the fuel tank shall not exceed one-quarter of the tank capacity or 5 gallons (19 L), whichever is less.
3108.14.2.2 Inspection. Fuel systems shall be inspected for leaks.
3108.14.2.3 Closure. Fuel tank openings shall be locked and sealed to prevent the escape of vapors.
3108.14.3 Location. The location of vehicles or equipment shall not obstruct means of egress.
CHBC § 9.1 Medium relevance — show source text
R104.9.1 Materials and equipment reuse. Materials, equipment and devices shall not be reused unless such elements are in good working condition and approved.
SECTION R105—PERMITS
R105.1 Required. Any owner or owner’s authorized agent who intends to construct, enlarge, alter, repair, move, demolish or change the occupancy of a building or structure, or to erect, install, enlarge, alter, repair, remove, convert or replace any electrical, gas, mechanical or plumbing system, the installation of which is regulated by this code, or to cause any such work to be performed, shall first make application to the building official and obtain the required permit.
R105.2 Work exempt from permit. Exemption from permit requirements of this code shall not be deemed to grant authorization for any work to be done in any manner in violation of the provisions of this code or any other laws or ordinances of this jurisdiction. Permits shall not be required for the following:
Building:
Other than storm shelters, one-story detached accessory structures, provided that the floor area does not exceed 120 square feet (11.15 m [2] ). It is permissible that these structures still be regulated by Part 7 California Wildland Urban-Interface Code, despite exemption from permit.
Fences not over 7 feet (2134 mm) high.
Retaining walls that are not over 4 feet (1219 mm) in height measured from the bottom of the footing to the top of the wall, unless supporting a surcharge.
Water tanks supported directly upon grade if the capacity does not exceed 5,000 gallons (18 927 L) and the ratio of height to diameter or width does not exceed 2 to 1.
Sidewalks and driveways.
Painting, papering, tiling, carpeting, cabinets, counter tops and similar finish work.
Prefabricated swimming pools that are less than 24 inches (610 mm) deep.
Swings and other playground equipment.
Window awnings supported by an exterior wall that do not project more than 54 inches (1372 mm) from the exterior wall and do not require additional support.
Decks not exceeding 200 square feet (18.58 m [2] ) in area, that are not more than 30 inches (762 mm) above grade at any point, are not attached to a dwelling or townhouse and do not serve the exit door required by Section R318.4.
Electrical:
- Listed cord-and-plug connected temporary decorative lighting.
- Reinstallation of attachment plug receptacles but not the outlets therefor.
- Replacement of branch circuit overcurrent devices of the required capacity in the same location.
- Electrical wiring, devices, appliances, apparatus or equipment operating at less than 25 volts and not capable of supplying more than 50 watts of energy.
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DIVISION II SCOPE AND ADMINISTRATION
- Minor repair work, including the replacement of lamps or the connection of approved portable electrical equipment to approved permanently installed receptacles.
Gas:
- Portable heating, cooking or clothes drying appliances.
- Replacement of any minor part that does not alter approval of equipment or make such equipment unsafe.
- Portable-fuel-cell appliances that are not connected to a fixed piping system and are not interconnected to a power grid.
Mechanical:
CHBC § 3-5 Medium relevance — show source text
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BUILDING PLANNING
R301.1.3 Engineered design. Where a building of otherwise conventional construction contains structural elements exceeding the limits of Section R301 or otherwise not conforming to this code, these elements shall be designed in accordance with accepted engineering practice. The extent of such design need only demonstrate compliance of nonconventional elements with other applicable provisions and shall be compatible with the performance of the conventional framed system. Engineered design in accordance with the California Building Code is permitted for buildings and structures, and parts thereof, included in the scope of this code.
R301.1.3.1 California licensed architect or engineer. When any portion of any structure deviates from substantial compliance with conventional framing requirements for woodframe construction found in this code, the building official shall require the construction documents to be approved and stamped by a California licensed architect or engineer for that irregular or non- conforming portion of work. Notwithstanding other sections of law, the law establishing these provisions is found in Business and Professions Code Sections 5537 and 6737.1.
R301.1.3.2 Woodframe structures greater than two-stories. The building official shall require construction documents to be approved and stamped by a California licensed architect or engineer for all dwellings of woodframe construction more than two stories and basement in height. Notwithstanding other sections of law, the law establishing these provisions is found in Business and Professions Code Sections 5537 and 6737.1.
R301.1.3.3 Structures other than woodframe. The building official shall require floor, wall or roof-ceiling structural elements in dwellings designed of cold-formed steel, concrete, masonry or structural insulated panels prescribed by this code to be approved and stamped by a California licensed architect or engineer. Notwithstanding other sections of law, the law establishing these provisions is found in Business and Professions Code Sections 5537 and 6737.1.
R301.1.4 Intermodal shipping containers. Intermodal shipping containers that are repurposed for use as buildings or structures shall be designed in accordance with the structural provisions in Section 3114 of the California Building Code .
R301.2 Climatic and geographic design criteria. Buildings shall be constructed in accordance with the provisions of this code as limited by the provisions of this section. Additional criteria shall be established by the local jurisdiction and set forth in Table R301.2.
TABLE R301.2—CLIMATIC AND GEOGRAPHIC DESIGN CRITERIA Col2 Col3 Col4 Col5 Col6 Col7 Col8 Col9 Col10 Col11 Col12 Col13 GROUND
SNOW
LOADo** WIND DESIGN** ** WIND DESIGN** ** WIND DESIGN** ** WIND DESIGN** ** SEISMIC**
DESIGN
CATEGORYf** SUBJECT TO DAMAGE FROM** ** SUBJECT TO DAMAGE FROM** ** SUBJECT TO DAMAGE FROM** ** ICE BARRIER**
UNDERLAYMEN
T REQUIREDh** FLOOD**
HAZARDSg** CHBC § 8-904.2.7 Medium relevance — show source text
8-904.2.7 Lighting load calculations for services and feeders may be based on actual loads as installed in lieu of the “watts per square foot” method.
8-904.2.8 Determination of existing loads may be based on maximum demand recordings in lieu of calculations, provided all of the following are met:
- Recordings are provided by the serving agency.
- The maximum demand data is available for a one-year period. Exception: If maximum demand data for a one-year period is not available, the maximum demand data shall be permitted to be based on the actual amperes continuously recorded over a minimum 30-day period by a recording ammeter connected to the highest loaded phase of the feeder or service. The recording should reflect the maximum demand when the building or space is occupied and include the measured or calculated load at the peak time of the year, including the larger of the heating or cooling equipment load.
- There has been no change in occupancy or character of load during the previous 12 months.
- The anticipated load will not change, or the existing demand load at 125 percent plus the new load does not exceed the ampacity of the feeder or rating of the service.
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8-10 QUALIFIED HISTORICAL DISTRICTS, SITES AND OPEN SPACES
SECTION 8-1001 — PURPOSE AND SCOPE
8-1001.1 Purpose. The purpose of this chapter is to provide regulations for the preservation, rehabilitation, restoration and reconstruction of associated historical features of qualified historical buildings, properties or districts (as defined in Chapter 8-2), and for which Chapters 8-3 through 8-9 of the CHBC may not apply.
8-1001.2 Scope. This chapter applies to the associated historical features of qualified historical buildings or properties such as historical districts that are beyond the buildings themselves which include, but are not limited to, natural features and designed site and landscape plans with natural and man-made landscape elements that support their function and aesthetics. This may include, but will not be limited to:
- Site plan layout configurations and relationships (pedestrian, equestrian and vehicular site circulation, topographical grades and drainage, and use areas).
- Landscape elements (plant materials, site structures other than the qualified historical building, bridges and their associated structures, lighting, water features, art ornamentation, and pedestrian, equestrian and vehicular surfaces).
- Functional elements (utility placement, erosion control and environmental mitigation measures).
SECTION 8-1002 — APPLICATION
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.
CHBC § 8-102.1.6 Medium relevance — show source text
8-102.1.6 Additional work. Qualified historical buildings or properties shall not be subject to additional work required by the regular code, regulation or ordinance beyond that required to complete the work undertaken. Certain exceptions for accessibility and for distinct hazards exist by mandate and may require specific action, within the parameters of the CHBC.
SECTION 8-103 — ORGANIZATION AND ENFORCEMENT
8-103.1 Authority. The state or local enforcing agency, pursuant to authority provided under Section 18954 of the Health and Safety Code, shall administer and enforce the provisions of the CHBC in permitting repairs, alterations and additions necessary for the preservation, restoration, reconstruction, rehabilitation, relocation or continued use of a qualified historical building or property.
8-103.2 State enforcement. All state agencies pursuant to authority provided under Section 18954 and Section 18961 of the Health and Safety Code shall administer and enforce the CHBC with respect to qualified historical buildings or properties under their respective jurisdiction.
8-103.3 Liability. Prevailing law regarding immunity of building officials is unaffected by the use and enforcement of the CHBC.
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ADMINISTRATION
SECTION 8-104 — REVIEW AND APPEALS
8-104.1 State Historical Building Safety Board (SHBSB or Board). In order to provide for interpretation of the provisions of the CHBC and to hear appeals, the SHBSB shall act as an appeal and review body to state and local agencies or any affected party.
8-104.2 SHBSB review. When a proposed design, material or method of construction is being considered by the enforcing agency, the agency chief, the building official or the local board of appeals may file a written request for opinion to the SHBSB for its consideration, advice or findings. In considering such request, the SHBSB may seek the advice of other appropriate private or public boards, individuals, or state or local agencies. The SHBSB shall, after considering all of the facts presented, including any recommendation of other appropriate boards, agencies or other parties, determine if, for the purpose intended, the proposal is reasonably equivalent to that allowed by these regulations in proposed design, material or method of construction, and it shall transmit such findings and its decision to the enforcing agency for its application. The Board may recover the costs of such reviews and shall report the decision in printed form, copied to the California Building Standards Commission.
8-104.2.1 State agencies. All state agencies with ownership of, or that act on behalf of state agency owners of, qualified historical buildings or properties, shall consult and obtain SHBSB review prior to taking action or making decisions or appeals that affect qualified historical buildings or properties, per Section 18961 of the Health and Safety Code.
8-104.2.2 Imminent threat. Where an emergency is declared and a qualified historical building or property is declared an imminent threat to life and safety, the state agency assessing such a threat shall consult with the SHBSB before any demolition is undertaken, per Section 18961 of the Health and Safety Code.
Frequently asked questions
Do the CHBC sections give trap and interceptor sizes?
No. The CHBC requires traps and interceptors to comply with the regular plumbing code but does not provide numeric sizes or sizing rules; use the applicable California Plumbing Code and local ordinances for sizing, then document compliance for the enforcing agency per § 8-903.6 .
Can I keep an existing S trap or drum trap in a historic building?
Yes — properly maintained “S” and drum traps may remain in use if the enforcing agency determines they do not create a safety hazard, per § 8-903.6 .
Where can vent terminations be located on a historic roof?
The CHBC allows vent terminations to be installed in any location that the enforcing agency judges will not create a safety hazard. Consult the enforcing agency early if you need nonstandard vent placement to preserve historic character (§ 8-903.4) .
What if my project proposes a nonstandard solution to preserve historic fabric?
The enforcing agency may approve alternatives that achieve equivalent safety. Be prepared to supply documentation, performance data, and possibly operational test results to demonstrate the solution does not increase the safety hazard (see § 8-903.1, § 8-903.4, § 8-903.6) .
Are chemical wastes allowed to go straight to the sewer?
No. Chemical or industrial liquid wastes that could detrimentally affect the sanitary sewer must be pretreated so they are safe prior to discharge (§ 8-903.5) .
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