Water supply, hot/cold requirements and testing

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

• CHBC § 1.859 High relevance — show source text

  78|–|1.859|0.463| |35.31|–|2.247|0.559| |38.84|–|2.667|0.663| |42.37|–|3.121|0.775| |45.90|–|3.607|0.895| |49.43|–|4.125|1.022| |52.97|–|–|1.157| |56.50|–|–|1.299| |60.03|–|–|1.449| |63.56|–|–|1.607| |67.09|–|–|1.772| |70.62|–|–|1.944| |81.21|–|–|2.503| |91.81|–|–|3.127| |102.40|–|–|3.813|

  For SI units: 1 standard cubic foot per minute = 28.32 SLPM, 1 inch = 25 mm, 1 foot = 304.8 mm, 1 pound-force per square inch = 6.8947 kPa

  Notes: 1 Based on pressure of 14.7 psig (101 kPa) at 68°F (20°C). 2 Based on pressure of 55 psig (379 kPa) at 68°F (20 °C).

  2025 CALIFORNIA PLUMBING CODE 291

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  HEALTH CARE FACILITIES AND MEDICAL GAS AND MEDICAL VACUUM SYSTEMS

  TABLE 1323.1.4(5) PRESSURE LOSS FOR VACUUM (continued)

  FLOW RATE (SCFM)1	VACUUM LOSS (inch of mercury) PER 100 FEET FOR COPPER TUBE2	Col3	Col4	Col5	Col6
  FLOW RATE (SCFM)1	3⁄4 INCH TUBE	1 INCH TUBE	11⁄4 INCH TUBE	11⁄2 INCH TUBE	2 INCH TUBE
  49.43	–	–	–	3.645	0.956
  52.97	–	–	–	4.122	1.081
  56.50	–	–	–	4.626	1.212
  63.56	–	–	–	–	1.495
  70.62	–	–	–	–	1.803
  77.68	–	–	–	–	2.138
  84.74	–	–	–	–	2.497
  91.81	–	–	–	–	2.882
  98.87	–	–	–	–	3.291
  105.93	–	–	–	–	3.724
  112.99	–	–	–	–	4.181

• CHBC § 13256-1 High relevance — show source text

  2 COP|ISO-13256-1| |Water source water-to-water
  (heating mode)|< 135,000 Btu/h
  (cooling capacity)|68ºF entering water|3.7 COP|ISO-13256-2| |Groundwater source water-to-
  water
  (heating mode)|< 135,000 Btu/h
  (cooling capacity)|50ºF entering water|3.1 COP|ISO-13256-2| |Ground source brine-to-water
  (heating mode)|< 135,000 Btu/h
  (cooling capacity)|32ºF entering water|2.5 COP|ISO-13256-2| |a. Deduct 0.2 from the required EERs and IEERs for units with a heating section other than electric resistance heat.
  b. Applicable test procedure and reference year are provided under the definitions.|a. Deduct 0.2 from the required EERs and IEERs for units with a heating section other than electric resistance heat.
  b. Applicable test procedure and reference year are provided under the definitions.|a. Deduct 0.2 from the required EERs and IEERs for units with a heating section other than electric resistance heat.
  b. Applicable test procedure and reference year are provided under the definitions.|a. Deduct 0.2 from the required EERs and IEERs for units with a heating section other than electric resistance heat.
  b. Applicable test procedure and reference year are provided under the definitions.|a. Deduct 0.2 from the required EERs and IEERs for units with a heating section other than electric resistance heat.
  b. Applicable test procedure and reference year are provided under the definitions.|

  TABLE 110.2-C—AIR-COOLED GAS-ENGINE HEAT PUMPS	Col2	Col3	Col4	Col5
  EQUIPMENT TYPE	SIZE CATEGORY	SUBCATEGORY OR RATING CONDITION	EFFICIENCY	TEST PROCEDUREa
  Air-cooled gas-engine heat pump (cooling mode)	All capacities	95°F db outdoor air	0.60 COP	ANSI Z21.40.4A
  Air-cooled gas-engine heat pump (heating mode)	All capacities	47°F db/43°F wb outdoor air	0.72 COP	ANSI Z21.40.4A
  a. Applicable test procedure and reference year are provided under the definitions.	a. Applicable test procedure and reference year are provided under the definitions.	a. Applicable test procedure and reference year are provided under the definitions.	a. Applicable test procedure and reference year are provided under the definitions.	a. Applicable test procedure and reference year are provided under the definitions.

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

  TABLE 110.2-D—WATER CHILLING PACKAGES—MINIMUM EFFICIENCY REQUIREMENTSa, b	Col2	Col3	Col4	Col5
  EQUIPMENT TYPE	SIZE CATEGORY	PATH A **EFFICIENCYa,

• CHBC § 87.9 High relevance — show source text

  9 kW) and larger| |Additions or
  Alterations|Zone terminal unit such as VAV box|Where existing zones served by the same air handling,
  chilled water, or hot water systems that have DDC| |Additions or
  Alterations|Air handling system or fan coil|Where existing air handling system(s) and fan coil(s)
  served by the same chilled or hot water plant have DDC| |Additions or
  Alterations|New air handling system and all
  new zones served by the system|Individual systems with design heating or cooling capacity of
  300 kBtu/h and larger and supplying more than three zones and
  more than 75 percent of zones are new| |Additions or
  Alterations|New or upgraded chilled water plant|Where all chillers are new and plant design cooling
  capacity is 300 kBtu/h (87.9 kW) and larger| |Additions or
  Alterations|New or upgraded hot water plant|Where all boilers are new and plant design heating
  capacity is 300 kBtu/h (87.9 kW) and larger|

  (k) Optimum start/stop controls. Space conditioning systems with DDC to the zone level shall have optimum start/stop controls. The control algorithm shall, as a minimum, be a function of the difference between space temperature and occupied setpoint, the outdoor air temperature, and the amount of time prior to scheduled occupancy. Mass radiant floor slab systems shall incorporate floor temperature onto the optimum start algorithm.

  Exception to Section 120.2(k): Systems that must operate continuously.

  (l) HVAC hot water temperature. Zones that use hot water for space heating shall be designed for a hot water supply temperature of no greater than 130°F.

  Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.8, and 25943, Public Resources Code.

  SECTION 120.3—REQUIREMENTS FOR PIPE INSULATION

  Nonresidential and hotel/motel buildings shall comply with the applicable requirements of Sections 120.3(a) through 120.3(c).

  (a) General requirements. The piping conditions listed below for space-conditioning, service water-heating, and process heating and process cooling systems piping with fluid normal operating temperatures listed in Table 120.3-A-1 or Table 120.3-A2, and the fluid distribution system, shall have at least the amount of insulation specified in Subsection (c):

  1. Space cooling systems. All refrigerant suction, chilled water, and brine fluid distribution systems.
  2. Space heating systems. All refrigerant suction, steam, steam condensate and hot water fluid distribution systems.
  3. Service water-heating systems. A. Recirculating system piping, including the supply and return piping to the water heater. B. The first 8 feet of hot and cold outlet piping, including piping between a storage tank and a heat trap, for a nonrecirculating storage system.

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  NONRESIDENTIAL, HOTEL/MOTEL OCCUPANCIES, AND COVERED PROCESSES—MANDATORY REQUIREMENTS

• 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 § 1.0 High relevance — show source text

  0| |Nonwater Urinal with Drain Cleansing Action|1⁄2|1.0|1.0|1.0| |Wash Fountain, circular spray|3⁄4|––|4.0|––| |Water Closet, 1.6 GPF Gravity Tank|1⁄2|2.5|2.5|3.5| |Water Closet, 1.6 GPF Flushometer Tank|1⁄2|2.5|2.5|3.5| |Water Closet, 1.6 GPF Flushometer Valve|1|See Footnote7|See Footnote7|––| |Water Closet, greater than 1.6 GPF Gravity Tank|1⁄2|3.0|5.5|7.0| |Water Closet, greater than 1.6 GPF Flushometer Valve|1|See Footnote7|See Footnote7|––|

  For SI units: 1 inch = 25 mm

  Notes: 1 Size of the cold branch pipe, or both the hot and cold branch pipes. 2 Appliances, appurtenances, or fixtures not referenced in this table shall be permitted to be sized by reference to fixtures having a similar flow rate and frequency of use. 3 The listed fixture unit values represent their load on the cold water building supply. The separate cold water and hot water fixture unit value for fixtures having both hot and cold water connections shall be permitted to be each taken as three-quarter of the listed total value of the fixture. 4 The listed minimum supply branch pipe sizes for individual fixtures are the nominal (I.D.) pipe size. 5 For fixtures or supply connections likely to impose continuous flow demands, determine the required flow in gallons per minute (gpm) (L/s), and add it separately to the demand in gpm (L/s) for the distribution system or portions thereof. 6 Assembly [Public Use (See Table 422.1)]. 7 Where sizing flushometer systems, see Section 610.10. 8 Reduced fixture unit loading for additional hose bibbs is to be used where sizing total building demand and for pipe sizing where more than one hose bibb is supplied by a segment of water distribution pipe. The fixture branch to each hose bibb shall be sized on the basis of 2.5 fixture units. 9 For water supply fixture unit values related to lots within mobilehome parks in all parts of the State of California, see California Code of Regulations, Title 25, Division 1, Chapter 2, Article 5, Section 1278. For water supply fixture unit values related to lots within special occupancy parks in all parts of the State of California, see California Code of Regulations, Title 25, Division 1, Chapter 2.2, Article 5, Section 2278.

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  WATER SUPPLY AND DISTRIBUTION

  Col1	Col2	TABLE 610.4 FIXTURE UNIT TABLE FOR DETERMINING WATER PIPE AND METER SIZES	Col4	Col5	Col6	Col7	Col8	Col9	Col10	Col11	Col12	Col13	Col14	Col15	Col16	Col17
  **METER

• CHBC § 25218.5 Medium relevance — show source text

  Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.8, and 25943, Public Resources Code.

  SECTION 120.3—REQUIREMENTS FOR PIPE INSULATION

  Nonresidential and hotel/motel buildings shall comply with the applicable requirements of Sections 120.3(a) through 120.3(c).

  (a) General requirements. The piping conditions listed below for space-conditioning, service water-heating, and process heating and process cooling systems piping with fluid normal operating temperatures listed in Table 120.3-A-1 or Table 120.3-A2, and the fluid distribution system, shall have at least the amount of insulation specified in Subsection (c):

  1. Space cooling systems. All refrigerant suction, chilled water, and brine fluid distribution systems.
  2. Space heating systems. All refrigerant suction, steam, steam condensate and hot water fluid distribution systems.
  3. Service water-heating systems. A. Recirculating system piping, including the supply and return piping to the water heater. B. The first 8 feet of hot and cold outlet piping, including piping between a storage tank and a heat trap, for a nonrecirculating storage system.

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  NONRESIDENTIAL, HOTEL/MOTEL OCCUPANCIES, AND COVERED PROCESSES—MANDATORY REQUIREMENTS

  C. Pipes that are externally heated. 4. Process heating system piping. All refrigerant, steam, steam condensate and hot water fluid distribution systems for heating a process unrelated to space conditioning or service water heating. 5. Process cooling system piping. All refrigerant suction, chilled water, and brine fluid distribution systems for cooling a process unrelated to space conditioning.

  Insulation conductivity shall be determined in accordance with ASTM C335 at the mean temperature listed in Table 120.3-A1 or Table 120.3-A2, and shall be rounded to the nearest [1] / 100 Btu-inch per hour per square foot per °F. Fluid distribution systems include all elements that are in series with the fluid flow, such as pipes, fittings, pumps, valves, strainers, coil u-bends, and air separators, but not including elements that are not in series with the fluid flow, such as expansion tanks, fill lines, chemical feeders, and drains.

  Exception to Section 120.3(a)2: Heat pump refrigerant vapor line shall be installed with a minimum of 0.5-inch-thick or R-3.0 insulation for nonresidential buildings and 0.75-inch-thick or R-6.0 insulation for residential buildings. No insulation is required on the refrigerant liquid line.

  (b) Insulation protection. Pipe insulation shall be protected from damage due to sunlight, moisture, equipment maintenance and wind. Protection shall, at minimum, include the following:

  1. Pipe insulation exposed to weather shall be protected by a cover suitable for outdoor service. The cover shall be water retardant and provides shielding from solar radiation that can cause degradation of the material. Adhesive tape shall not be used to provide this protection.
• CHBC § 25.4 Medium relevance — show source text

  For SI units: 1 inch = 25.4 mm, °C = (°F-32)/1.8

  FIGURE 511.1.2(1) TYPICAL SECTION OF DUCT-TO-FAN

  CONNECTION-BUTT JOINT METHOD

  [NFPA 96: FIGURE 8.1.3.2(a)]

  For SI units: 1 inch = 25.4 mm, °C = (°F-32)/1.8

  FIGURE 511.1.2(2) TYPICAL SECTION OF DUCT-TO-FAN

  CONNECTION-OVERLAPPING METHOD

  [NFPA 96: FIGURE 8.1.3.2(b)]

  and exhaust fans that do not meet this velocity. [NFPA 96:8.2.1.2]

  511.2.2 Exhaust-Air Volumes. Exhaust air volumes for hoods shall be of sufficient level to provide for capture and removal of grease-laden cooking vapors. Test data, performance tests acceptable to the Authority Having Jurisdiction, or both shall be displayed, provided on request, or both. [NFPA 96:8.2.2.1, 8.2.2.2] Lower exhaust air volumes shall be permitted during no-load and partial load cooking conditions, provided they are sufficient to capture and remove flue gases and cooking effluent from cooking equipment.

  For SI units: 1 inch = 25.4 mm, °C = (°F-32)/1.8)

  FIGURE 511.1.2(3) TYPICAL SECTION OF DUCT-TO-FAN

  CONNECTION–SEALANT METHOD

  [NFPA 96: FIGURE 8.1.3.2(c)]

  FIGURE 511.1.2(4) TYPICAL SECTION OF DUCT-TO-FAN CONNECTION-DIRECT

  TO FAN INLET CONE METHOD

  [NFPA 96: FIGURE 8.1.3.2(d)]

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  EXHAUST SYSTEMS

  511.2.2.1 Performance Test. A performance test shall be conducted upon completion and before final approval of the installation of a ventilation system serving commercial cooking appliances. The test shall verify the rate of exhaust airflow in accordance with Section 508.5.1.2 through Section 508.5.1.5. The permit holder shall furnish the necessary test equipment and devices required to perform the tests.

  [ASHRAE 154:4.7.1]

  511.2.2.2 Capture and Containment Test. The permit holder shall verify the capture and containment performance of Type I hoods. A field test shall be conducted with all appliances under the hood at operating temperatures, all the hoods operating at design airflows, and with all sources of replacement air operating at design airflows for the restaurant. Capture and containment shall be verified visually by observing smoke or steam produced by actual cooking operation or by simulating cooking using devices such as smoke candles or smoke puffers. Smoke bombs shall not be used. [ASHRAE 154:4.7.2]

• CHBC § 6.8 Medium relevance — show source text

  (b) Solar water-heating systems and collectors shall be certified and rated by the Solar Rating and Certification Corporation (SRCC), the International Association of Plumbing and Mechanical Officials, Research and Testing (IAPMO R&T), or a listing agency that is approved by the Executive Director.

  (c) Instantaneous water heaters with an input rating greater than 6.8 kBTU/hr (2kW) shall meet the requirements of Section 110.3(c)6.

  (d) Commercial boilers

  1. Combustion air positive shut-off shall be provided on all newly installed boilers as follows: A. All boilers with an input capacity of 2.5 MMBtu/h (2,500,000 Btu/h) and above, in which the boiler is designed to operate with a nonpositive vent static pressure. B. All boilers where one stack serves two or more boilers with a total combined input capacity per stack of 2.5 MMBtu/h (2,500,000 Btu/h).
  2. Boiler combustion air fans with motors 10 horsepower or larger shall meet one of the following for newly installed boilers: A. The fan motor shall be driven by a variable speed drive, or B. The fan motor shall include controls that limit the fan motor demand to no more than 30 percent of the total design wattage at 50 percent of design air volume.
  3. Newly installed boilers with an input capacity 5 MMBtu/h (5,000,000 Btu/h) and greater shall maintain excess (stack-gas) oxygen concentrations at less than or equal to 5.0 percent by volume on a dry basis over firing rates of 20 percent to 100 percent. Combustion air volume shall be controlled with respect to firing rate or flue gas oxygen concentration. Use of a common gas and combustion air control linkage or jack shaft is prohibited. Exception to Section 160.4(d)3: Boilers with steady state full-load thermal combustion efficiency 90 percent or higher.

  (e) Pipe insulation

  All piping for multifamily domestic hot water systems shall be insulated and meet the applicable requirements in Items 1 through 3 below:

  1. General requirements. A. The first 8 feet of inlet cold water piping from the storage tanks, including piping between a storage tank and a heat trap, shall be insulated. B. Insulation on the piping and domestic hot water system appurtenances shall be continuous. C. Pipe supports, hangers, and pipe clamps shall be attached on the outside of rigid pipe insulation to prevent thermal bridges. D. All pipe insulation seams shall be sealed. E. Insulation for pipe elbows shall be mitered, preformed, or site fabricated with PVC covers. F. Insulation for tees shall be notched, preformed, or site fabricated with PVC covers.

  G. Extended stem isolation valves shall be installed.

  H. All plumbing appurtenances on hot water piping from a heating source to heating plant, at the heating plant, and distribution supply and return piping shall be insulated to meet the following requirements: i. Where the outer diameter of the appurtenance is less than the outer diameter of the insulated pipe that it is attached to, the appurtenance shall be insulated flush with the insulation surrounding the pipe. ii. Where the outer diameter of the appurtenance is greater than the outer diameter of the insulated pipe that it is attached to, the appurtenance shall be insulated with a minimum thickness of 1 inch. iii. The insulation shall be removable and re-installable to ensure maintenance or replacement services can be completed. iv. Valves shall be fully functional without impediment from the insulation.

• CHBC § 110.3 Medium relevance — show source text

  1. Outlet temperature controls. On systems that have a total capacity greater than 167,000 Btu/hr, outlets that require higher than service water temperatures as listed in the ASHRAE Handbook, Applications Volume, shall have separate remote heaters, heat exchangers or boosters to supply the outlet with the higher temperature. Exception to Section 110.3(c)1: Systems covered by California Plumbing Code Section 613.0 shall instead follow the requirements of that section.
  2. Controls for hot water distribution systems. Service hot water systems with circulating pumps or with electrical heat trace systems shall be capable of automatically turning off the system. Exception to Section 110.3(c)2: Systems serving healthcare facilities.
  3. Insulation. Unfired service water heater storage tanks and backup tanks for solar water-heating systems shall have: A. External insulation with an installed R -value of at least R-3.5; or

  B. Internal and external insulation with a combined R -value of at least R-16; or

  C. The heat loss of the tank surface based on an 80°F water-air temperature difference shall be less than 6.5 Btu per hour per square foot. 4. Water heating recirculation loops serving multiple dwelling units, high-rise residential, hotel/motel, and nonresiden- tial occupancies. A water heating recirculation loop is a type of hot water distribution system that reduces the time needed to deliver hot water to fixtures that are distant from the water heater, boiler or other water heating equipment. The recirculation loop is comprised of a supply portion, connected to branches that serve multiple dwelling units, guest rooms, or fixtures and a return portion that completes the loop back to the water heating equipment. A water heating recirculation loop shall meet the following requirements: A. Air release valve or vertical pump installation. An automatic air release valve shall be installed on the recirculation loop piping on the inlet side of the recirculation pump and no more than 4 feet from the pump. This valve shall be mounted on top of a vertical riser at least 12 inches in length and shall be accessible for replacement and repair. Alternatively, the pump shall be installed on a vertical section of the return line. B. Recirculation loop backflow prevention. A check valve or similar device shall be located between the recirculation pump and the water heating equipment to prevent water from flowing backwards though the recirculation loop. C. Equipment for pump priming. A hose bibb shall be installed between the pump and the water heating equipment. An isolation valve shall be installed between the hose bibb and the water heating equipment. This hose bibb is used for bleeding air out of the pump after pump replacement. D. Pump isolation valves. Isolation valves shall be installed on both sides of the pump. These valves may be part of the flange that attaches the pump to the pipe. One of the isolation valves may be the same isolation valve as in Item C. E. Cold water supply and recirculation loop connection to hot water storage tank. Storage water heaters and boilers shall be plumbed in accordance with the manufacturer’s specifications The cold water piping and the recirculation loop piping shall not be connected to the hot water storage tank drain port. F. Cold water supply backflow prevention. A check valve shall be installed on the cold water supply line between the hot water system and the next closest tee on the cold water supply line.

• CHBC § 0.228 Medium relevance — show source text

  657|0.228|0.096|0.025| |19.77|2.750|0.699|0.243|0.102|0.026| |20.48|2.925|0.744|0.258|0.109|0.028| |21.19|3.106|0.790|0.274|0.115|0.030| |24.72|4.074|1.034|0.358|0.151|0.039| |28.25|–|1.307|0.452|0.190|0.049| |31.78|–|1.608|0.556|0.234|0.060| |35.31|–|1.936|0.669|0.281|0.072| |38.84|–|2.291|0.791|0.332|0.085| |42.37|–|2.672|0.922|0.387|0.099| |45.90|–|3.078|1.062|0.446|0.113| |49.43|–|3.510|1.211|0.508|0.129| |52.97|–|3.969|1.368|0.574|0.146| |56.50|–|4.450|1.534|0.643|0.163| |63.56|–|–|1.890|0.792|0.201| |70.62|–|–|2.278|0.954|0.242| |77.68|–|–|2.699|1.130|0.286| |84.74|–|–|3.151|1.318|0.334| |91.81|–|–|3.634|1.520|0.385| |98.87|–|–|4.148|1.734|0.439| |105.93|–|–|4.691|1.961|0.496| |112.99|–|–|–|2.200|0.556|

  For SI units: 1 standard cubic foot per minute = 28.32 SLPM, 1 inch = 25 mm, 1 foot = 304.8 mm, 1 inch of mercury = 3.386 kPa Notes: 1 Based on the pressure of 14.7 psig (101 kPa) at 68°F (20°C). 2 Based on the pressure of 19 inches of mercury gauge vacuum (64 kPa) at 68°F (20°C).

  1323.3 Location of Piping. Piping risers shall be permitted to be installed in pipe shafts if protected from physical damage, effects of excessive heat, corrosion, or contact with oil. [NFPA 99:5.1.10.11.3.1] 1323.3.1 Prohibited Locations. Piping shall not be installed in kitchens, stairwells, elevator shafts, elevator machine rooms, areas with open flames, electrical service equipment over 600 volts, and areas prohibited Cal- ifornia Electrical Code except for the following locations:

  (1) Room locations for medical air compressor supply systems and medical-surgical vacuum pump supply systems

  (2) Room locations for secondary distribution circuit panels and breakers having a maximum voltage rating of 600 volts [NFPA 99:5.1.10.11.3.2] **1323.3.2 Approved Locations.

• CHBC § 503.4.6.3.1 Medium relevance — show source text

  (11) Systems serving residential spaces other than hotel/motel guest rooms shall comply with Section E 503.4.6.3.1 and Section E 503.4.6.3.2 except for electric resistance heaters rated at 5000 Btu/h (1.5 kW) or less with a readily accessible manual control that lowers the set point or turns the unit off.

  (12) Systems serving hotel/motel guest rooms shall comply with Section E 503.4.6.3.5.

  (13) Except for piping within manufacturer’s units, HVAC piping shall be insulated in accordance with Table E 503.7.3(1) and Table E 503.7.3(2). Insulation exposed to weather shall be suitable for outdoor service, e.g., protected by aluminum, sheet metal, painted canvas, or plastic cover. Cellular foam insulation shall be protected as above or painted with a coating that is water retardant and provides shielding from solar radiation.

  (14) Ductwork and plenums shall be insulated in accordance with Table E 503.7.2 and shall be sealed in

  accordance with Section E 503.4.7.2.

  (15) Construction documents shall require a ducted system to be air balanced in accordance with industryaccepted procedures.

  (16) Outdoor air intake and exhaust systems shall comply with Section E 503.4.6.4 through Section E 503.4.6.5.

  (17) Where separate heating and cooling equipment serves the same temperature zone, thermostats shall be interlocked to prevent simultaneous heating and cooling.

  (18) Systems with a design supply air capacity more than 10 000 ft [3] /min (4.7195 m [3] /s) shall have optimum start controls.

  (19) The system shall comply with the demand control ventilation requirements of Section E 503.4.6.9, occupied-standby controls in Section E 503.5.6.8, and the ventilation design requirements of Section E 503.5.6.7.

  (20) The system shall comply with the door switch requirements of Section E 503.5.14. [ASHRAE 90.1:6.3.2]

  E 503.3.2 Climate Zone Determination. Climate zones identified in this appendix shall be determined in accordance with ASHRAE 90.1. For locations in the United States and its territories, the assigned climate zone and, where required, the assigned climate zone letter shall be in accordance with ASHRAE 169.

  Exception: Where recorded historical climatic data are available for a construction site, it is permitted to be used to determine compliance where approved by the Authority Having Jurisdiction. [ASHRAE 90.1:5.1.4.1]

  E 503.4 Equipment Efficiencies, Verification, and Labeling Requirements. Equipment shown in Table E 503.7.1(1) through Table E 503.7.1(20) shall have a minimum performance at the specified rating conditions when tested in accordance with the specified test procedure. Where multiple rating conditions or performance requirements are provided, the equipment shall satisfy all stated requirements unless otherwise exempted by footnotes in the table. Equipment covered under the Federal Energy Policy Act of 1992 (EPACT) shall have no minimum efficiency requirements for operation at minimum capacity or other than standard rating conditions. Equipment used to provide service water-heating functions as part of a combination system shall satisfy all stated requirements for the appropriate space heating or cooling category.

• CHBC § 3.2.2 Medium relevance — show source text

  1810 A .3.2.2 Prestressing steel. Prestressing steel shall conform to ASTM A416.

  1810 A .3.2.3 Steel. Structural steel H-piles and structural steel sheet piling shall conform to the material requirements in ASTM A6. Steel pipe piles shall conform to the material requirements in ASTM A252. Fully welded steel piles shall be fabricated from plates that conform to the material requirements in ASTM A36, ASTM A283, ASTM A572, ASTM A588 or ASTM A690.

  1810 A .3.2.4 Timber. Not permitted by DSA-SS, DSA-SS/CC or OSHPD.

  1810 A .3.2.5 Protection of materials. Where boring records or site conditions indicate possible deleterious action on the materials used in deep foundation elements because of soil constituents, changing water levels or other factors, the elements shall be adequately protected by materials, methods or processes approved by the building official. Protective materials shall be applied to the elements so as not to be rendered ineffective by installation. The effectiveness of such protective measures for the particular purpose shall have been thoroughly established by satisfactory service records or other evidence.

  1810 A .3.2.6 Allowable stresses. The allowable stresses for materials used in deep foundation elements shall not exceed those specified in Table 1810 A .3.2.6.

  TABLE 1810A.3.2.6—ALLOWABLE STRESSES FOR MATERIALS USED IN DEEP FOUNDATION ELEMENTS	Col2
  MATERIAL TYPE AND CONDITION	MAXIMUM ALLOWABLE STRESSa
  1. Concrete or grout in compressionb Cast-in-place with a permanent casing in accordance with Section 1810_A_.3.2.7 or Section 1810_A_.3.5.3.4 Cast-in-place in other permanent casing or rock Cast-in-place without a permanent casing Precast nonprestressed Precast prestressed	0.4_f ′c_ 0.33_f ′c_ 0.3_f ′c_ 0.33_f ′c_ 0.33_f ′c_ - 0.27_fpc_
  2. Nonprestressed reinforcement in compression	0.4_fy_ ≤ 30,000 psi
  3. Steel in compression Cores within concrete-filled pipes or tubes Pipes, tubes or H-piles, where justified in accordance with Section 1810.3.2.8 Pipes or tubes for micropiles Other pipes, tubes or H-piles Helical piles	0.5_Fy_ ≤ 32,000 psi 0.5_Fy ≤ 32,000 psi 0.4_Fy ≤ 32,000 psi 0.35_Fy_ ≤ 24,000 psi 0.6_Fy_ ≤ 0.5_Fu_
  4. Nonprestressed reinforcement in tension Within micropiles Other conditions For load combinations that do not include wind or seismic loads For load combinations that include wind or seismic loads	0.6_fy_ 0.5_fy_ ≤ 30,000 psi 0.5_fy_ ≤ 40,000 psi
  5.

• CHBC § 8-903.2 Medium 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 § 1505.7 Medium relevance — show source text

  (2) Reclaimed (recycled) water systems for outdoor applications shall be marked in accordance with this section with the words: “CAUTION: NONPOTABLE RECLAIMED (RECYCLED) WATER, DO NOT DRINK” in black letters.

  (3) On-site treated water systems shall be marked in accordance with this section with the words: “CAU TION: ON-SITE TREATED NONPOTABLE WATER, DO NOT DRINK” in black letters.

  (4) Rainwater catchment systems shall be marked in accordance with this section with the words: “CAU TION: NONPOTABLE RAINWATER, DO NOT DRINK” in black letters.

  Exception: [DWR] For recycled water supply systems that are within or a part of a building, the provisions of Section 1505.7 shall apply.

  TABLE 601.3.2

  MINIMUM LENGTH OF COLOR FIELD AND SIZE OF LETTERS

  OUTSIDE DIAMETER OF PIPE OR COVERING (inches)	MINIMUM LENGTH OF COLOR FIELD (inches)	MINIMUM SIZE OF LETTERS (inches)
  1⁄2 to 11⁄4	8	1⁄2
  11⁄2 to 2	8	3⁄4
  21⁄2 to 6	12	11⁄4
  8 to 10	24	21⁄2
  Over 10	32	31⁄2

  For SI units: 1 inch = 25.4 mm

  601.3.4 Fixtures. Where vacuum breakers or backflow preventers are installed with fixtures listed in Chapter 17, identification of the discharge side shall be permitted to be omitted.

  601.3.5 Outlets. Each outlet on the nonpotable water line that is used for special purposes shall be posted with black uppercase lettering as follows: “CAUTION: NONPOTABLE WATER, DO NOT DRINK.”

  601.4 Schools of Cosmetology and Cosmetological Establishments. [CA]

  601.4.1 Hot- and Cold-Running Water. At least one sink with hot-and cold-running water shall be provided in each work area or workroom where hairdressing is performed in each school and establishment. 601.4.2 Handwashing Facilities. Each school and establishment shall provide adequate handwashing facil- ities, including hot-and cold-running water, located within or adjacent to the toilet room or rooms in accor- dance with Table 422.1.

  601.4.3 Drinking Water. Each school and establishment shall supply potable drinking water convenient to students, patrons and employees. Approved sanitary drinking foun- tains shall be installed and so regulated that a jet of at least 2 inches (51 mm) shall be constantly available.

  601.5 Meat and Poultry Processing Plants. [AGR] Except as provided in Section 601.5.4, the water supply shall be ample and potable, with adequate pressure and facilities for its distribution in the plant, and its protection against con- tamination and pollution.

• 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.

  2025 CALIFORNIA HISTORICAL BUILDING CODE 19

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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 § 1.5 Medium relevance — show source text

  5**|1.5 to < 4|4 to < 8|8 and
  larger| |Space heating (Steam, Steam Condensate, Refrigerant, Space Heating)|Space heating (Steam, Steam Condensate, Refrigerant, Space Heating)|Space heating (Steam, Steam Condensate, Refrigerant, Space Heating)|Space heating (Steam, Steam Condensate, Refrigerant, Space Heating)|Minimum Pipe Insulation Required (Thickness in inches or_R-_value)|Minimum Pipe Insulation Required (Thickness in inches or_R-_value)|Minimum Pipe Insulation Required (Thickness in inches or_R-_value)|Minimum Pipe Insulation Required (Thickness in inches or_R-_value)|Minimum Pipe Insulation Required (Thickness in inches or_R-_value)| |Below 40|0.20–0.26|50|Inches|1.0|1.5|1.5|1.5|1.5| |Below 40|0.20–0.26|50|_R-_value|R-8.5|R-14|R-12|R-10|R-9| |1. These thicknesses are based on energy efficiency considerations only. Issues such as water vapor permeability or surface condensation sometimes require vapor retarders or
  additional insulation.|1. These thicknesses are based on energy efficiency considerations only. Issues such as water vapor permeability or surface condensation sometimes require vapor retarders or
  additional insulation.|1. These thicknesses are based on energy efficiency considerations only. Issues such as water vapor permeability or surface condensation sometimes require vapor retarders or
  additional insulation.|1. These thicknesses are based on energy efficiency considerations only. Issues such as water vapor permeability or surface condensation sometimes require vapor retarders or
  additional insulation.|1. These thicknesses are based on energy efficiency considerations only. Issues such as water vapor permeability or surface condensation sometimes require vapor retarders or
  additional insulation.|1. These thicknesses are based on energy efficiency considerations only. Issues such as water vapor permeability or surface condensation sometimes require vapor retarders or
  additional insulation.|1. These thicknesses are based on energy efficiency considerations only. Issues such as water vapor permeability or surface condensation sometimes require vapor retarders or
  additional insulation.|1. These thicknesses are based on energy efficiency considerations only. Issues such as water vapor permeability or surface condensation sometimes require vapor retarders or
  additional insulation.|1. These thicknesses are based on energy efficiency considerations only. Issues such as water vapor permeability or surface condensation sometimes require vapor retarders or
  additional insulation.|

  NOTE: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code . Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.5, 25402.8 and 25943, Public Resources Code .

  SECTION 160.4—MANDATORY REQUIREMENTS FOR WATER-HEATING SYSTEMS

  (a) Water-heating recirculation loops serving multiple dwelling units shall meet the requirements of Section 110.3(c)4.

• California Historical Building Code Medium relevance — show source text

  |100 psf|1 hr
  23 min|||7|1, 2|11/3| |F/C-4-RC-9|4″|4″ deep (4370 psi);1/4″ reinforcement bars
  at 6″ pitch with3/4″ cover;1/4″ main rein-
  forcement bars at 4″ pitch perpendicular
  with1/2″ cover; 13′1″ span restrained.|150 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-10|4″|4″ thick (5140 psi) deck;1/4″ reinforce-
  ment bars at 71/2″ pitch with7/8″ cover;3/8″
  main reinforcement bars at 33/4″ pitch
  perpendicular with1/2″ cover; 13′1″ span
  restrained.|140 psf|1 hr
  16 min|||7|1, 5|11/4| |F/C-4-RC-11|4″|4″ thick (4000 psi) concrete deck;
  3″ × 11/2″ × 4 lbs R.S.J.; 2′6″ C.R.S.; flush
  with top surface; 4″ × 6″ x 13 SWG mesh
  reinforcement 1″ from bottom of slab; 6′6″
  span restrained.|150 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-12|4″|4″ deep (2380 psi) concrete deck;
  3″ × 11/2″ × 4 lbs R.S.J.; 2′6″ C.R.S.; flush
  with top surface; 4″ × 6″ x 13 SWG mesh
  reinforcement 1″ from bottom surface;
  6′6″ span restrained.|150 psf|1 hr
  3 min|||7|1, 2|1| |F/C-4-RC-13|41/2″|41/2″ thick (5200 psi) deck;1/4″ reinforce-
  ment bars at 71/4″ pitch with7/8″ cover;3/8″
  main reinforcement bars at 33/4″ pitch
  perpendicular with1/2″ cover; 13′1″ span
  restrained.|140 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-14|41/2″|41/2″ deep (2525 psi) concrete deck;1/4″
  reinforcement bars at 71/2″ pitch with7/8″
  cover;3/8″ main reinforcement bars at
  33/8″ pitch perpendicular with1/2″ cover;
  13′1″ span restrained.|150 psf|42 min|||7|1, 5|2/3| |F/C-4-RC-15|41/2″|41/2″ deep (4830 psi) concrete deck;
  11/2″ × No.

• CHBC § 140.4 Medium relevance — show source text

  30 percent of the peak heat rejection of the cooling system; or B. 30 percent of SWHCAP.

  Exception to Section 140.4(s): Buildings with a computer room heat recovery system or wastewater heat recovery system capable of providing not less than 25 percent of SWHCAP + HCAP.

  Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.8, and 25943, Public Resources Code .

  SECTION 140.5—PRESCRIPTIVE REQUIREMENTS FOR SERVICE WATER-HEATING SYSTEMS

  (a) Nonresidential occupancies. Service water-heating systems in nonresidential buildings shall meet the requirements of 1 or 2 below, or meet the performance compliance requirements of Section 140.1:

  1. School buildings less than 25,000 square feet and less than 4 stories in Climate Zones 2 through 15. A heat pump water-heating system that meets the applicable requirements of Sections 110.1, 110.3 and 120.3.

  Exception to Section 140.5(a)1: A water-heating system serving an individual bathroom space may be an instantaneous electric water heater.

  2. All other occupancies. A service water-heating system that meets the applicable requirements of Sections 110.1, 110.3, 120.3 and 140.5(c).

  (b) Hotel/motel occupancies. A service water-heating system installed in hotel/motel buildings shall meet the requirements of Section 170.2(d).

  (c) High-capacity service water-heating systems . Gas service water-heating systems with a total installed gas water-heating input capacity of 1 MMBtu/h or greater shall have gas service water-heating equipment with a minimum thermal efficiency of 90 percent. Multiple units can meet this requirement if the water-heating input provided by equipment with thermal efficiencies above and below 90 percent averages out to an input capacity-weighted average of at least 90 percent.

  Exception 1 to Section 140.5(c): If 25 percent of the annual service water-heating requirement is provided by site-solar energy or site-recovered energy.

  Exception 2 to Section 140.5(c): Water heaters installed in individual dwelling units.

  Exception 3 to Section 140.5(c): Individual gas water heaters with input capacity at or below 100,000 Btu/h shall not be included in the calculations of the total system input or total system efficiency.

  Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.8, and 25943, Public Resources Code.

  2025 CALIFORNIA ENERGY CODE 129

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

  NONRESIDENTIAL AND HOTEL/MOTEL OCCUPANCIES—PERFORMANCE AND PRESCRIPTIVE

  COMPLIANCE APPROACHES FOR ACHIEVING ENERGY EFFICIENCY

  SECTION 140.6—PRESCRIPTIVE REQUIREMENTS FOR INDOOR LIGHTING

• 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
  holes prior to installation.|

  18 2025 CALIFORNIA HISTORICAL BUILDING CODE

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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 § 8-903.3 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.

  20 2025 CALIFORNIA HISTORICAL BUILDING 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.

• California Historical Building Code Medium relevance — show source text

  ; 2′ C.R.S. with 1″ cover on
  both top and bottom flanges; 13′1″ span
  restrained.|60 psf|2 hrs|||7|1, 3|2| |F/C-6-RC-34|61/4″|61/4″ thick; 43/4″ (5120 psi) concrete core;
  1″ T&G board flooring;1/2″ plaster under-
  coat; 4″ × 3″ × 10 lbs R.S.J.; 3′ C.R.S. flush
  with top surface concrete; 12′ span simply
  supported; 2″ × 1′3″ clinker concrete
  insert.|100 psf|4 hrs|||7|1, 7|4| |F/C-6-RC-35|61/4″|43/4″ (3600 psi) concrete core; 1″ T&G
  board flooring;1/2″ plaster undercoat; 4″ ×
  3″ × 10 lbs R.S.J.; 3′ C.R.S. flush with top
  surface concrete; 12′ span simply
  supported; 2″ × 1′3″ clinker concrete
  insert.|100 psf|2 hrs
  30 min|||7|1, 5|21/2| |F/C-6-RC-36|61/4″|43/4″ (2800 psi) concrete core; 1″ T&G
  board flooring;1/2″ plaster undercoat; 4″ ×
  3″ × 10 lbs R.S.J.; 3′ C.R.S. flush with top
  surface concrete; 12″ span simply
  supported; 2″ × 1′3″ clinker concrete
  insert.|80 psf|4 hrs|||7|1, 7|4| |F/C-7-RC-37|7″|(3640 psi) concrete deck;1/4″ reinforce-
  ment bars at 6″ pitch with 11/2″ cover;1/4″
  reinforcement bars at 5″ pitch perpendic-
  ular with 11/2″ cover; 13′1″ span
  restrained.|169 psf|6 hrs|||7|1, 14|6| |F/C-7-RC-38|7″|(4060 psi) concrete deck; 4″ × 3″ × 10 lbs
  R.S.J.; 2′6″ C.R.S. with 11/2″ cover on both
  top and bottom flanges; 4″ × 6″ × 13 SWG
  mesh reinforcement 11/2″ from bottom of
  slab; 13′1″ span restrained.|175 psf|6 hrs|||7|1, 14|6| |F/C-7-RC-39|71/4″|53/4″ (4010 psi) concrete core; 1″ T&G
  board flooring;1/2″ plaster undercoat;
  4″ × 3″ × 10 lbs R.S.J.; 2′6″ C.R.S.