What insulation and sizing requirements apply to refrigerated warehouses and refrigerated spaces?

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

• § 10-103.2 High relevance — show source text

  (b) When certification is required by Title 24, Part 1, Section 10-103.2, the acceptance testing specified by Section 120.5(a) shall be performed by a certified mechanical acceptance test technician (CMATT). If the CMATT is operating as an employee, the CMATT shall

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

  be employed by a certified mechanical acceptance test employer. The CMATT shall disclose on the certificate of acceptance a valid CMATT certification identification number issued by an approved acceptance test technician certification provider. The CMATT shall complete all certificate of acceptance documentation in accordance with the applicable requirements in Section 10-103(a)4.

  Note: Authority cited: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402(a)-(b), 25402.1, 25402.4, 25402.5, 25402.8 and 25943, Public Resources Code .

  SECTION 120.6—MANDATORY REQUIREMENTS FOR COVERED PROCESSES

  Nonresidential and hotel/motel buildings shall comply with the applicable requirements of Sections 120.6(a) through 120.6(k), and the applicable requirements of Sections 110.2(a) and 120.3.

  (a) Mandatory requirements for refrigerated warehouses.

  Refrigerated warehouses that are greater than or equal to 3,000 square feet and refrigerated spaces with a sum total of 3,000 square feet or more that are served by the same refrigeration system shall meet the requirements of Section 120.6(a).

  Refrigerated spaces that are less than 3,000 square feet shall meet the requirements of the Appliance Efficiency Regulations for walk-in coolers or freezers contained in the Appliance Efficiency Regulations (California Code of Regulations, Title 20, Sections 1601 through 1608).

  1. Insulation requirements. Exterior surfaces of refrigerated warehouses shall be insulated at least to the R -values in Table 120.6-A-1.

  TABLE 120.6-A-1—REFRIGERATED WAREHOUSE INSULATION	Col2	Col3
  SPACE	SURFACE	MNIMUMR-VALUE (ºF·hr·sf/Btu)
  Freezers	Roof/ceiling	R-40
  Freezers	Wall	R-36
  Freezers	Floor	R-35
  Freezers	Floor with all heating from productive refrigeration capacity1	R-20
  Coolers	Roof/ceiling	R-28
  Coolers	Wall	R-28
  1. All underslab heating is provided by a heat exchanger that provides refrigerant subcooling or other means that result in productive refrigeration capacity on the associated refrigerated system.	1. All underslab heating is provided by a heat exchanger that provides refrigerant subcooling or other means that result in productive refrigeration capacity on the associated refrigerated system.	1. All underslab heating is provided by a heat exchanger that provides refrigerant subcooling or other means that result in productive refrigeration capacity on the associated refrigerated system.

  2. **Underslab heating.
• § 120.6 High relevance — show source text

  Refrigerated spaces that are less than 3,000 square feet shall meet the requirements of the Appliance Efficiency Regulations for walk-in coolers or freezers contained in the Appliance Efficiency Regulations (California Code of Regulations, Title 20, Sections 1601 through 1608).

  1. Insulation requirements. Exterior surfaces of refrigerated warehouses shall be insulated at least to the R -values in Table 120.6-A-1.

  TABLE 120.6-A-1—REFRIGERATED WAREHOUSE INSULATION	Col2	Col3
  SPACE	SURFACE	MNIMUMR-VALUE (ºF·hr·sf/Btu)
  Freezers	Roof/ceiling	R-40
  Freezers	Wall	R-36
  Freezers	Floor	R-35
  Freezers	Floor with all heating from productive refrigeration capacity1	R-20
  Coolers	Roof/ceiling	R-28
  Coolers	Wall	R-28
  1. All underslab heating is provided by a heat exchanger that provides refrigerant subcooling or other means that result in productive refrigeration capacity on the associated refrigerated system.	1. All underslab heating is provided by a heat exchanger that provides refrigerant subcooling or other means that result in productive refrigeration capacity on the associated refrigerated system.	1. All underslab heating is provided by a heat exchanger that provides refrigerant subcooling or other means that result in productive refrigeration capacity on the associated refrigerated system.

  2. Underslab heating. Electric resistance heat shall not be used for the purposes of underslab heating. Exception to Section 120.6(a)2: Underslab heating systems controlled such that the electric resistance heat is thermostatically controlled and disabled during the summer on-peak period defined by the local electric utility.
  3. Evaporators. New fan-powered evaporators used in coolers and freezers shall conform to the following: A. Single phase fan motors less than 1 hp and less than 460 Volts in newly installed evaporators shall be electronicallycommutated motors or shall have a minimum motor efficiency of 70 percent when rated in accordance with NEMA Standard MG 1-2006 at full load rating conditions. B. Evaporator fans served either by a suction group with multiple compressors or by a single compressor with variable capacity capability shall be variable speed and the speed shall be controlled in response to space temperature or humidity. Exception 1 to Section 120.6(a)3B: Addition, alteration or replacement of less than all of the evaporators in an existing refrigerated space that does not have speed-controlled evaporators. Exception 2 to Section 120.6(a)3B: Coolers within refrigerated warehouses that maintain a controlled atmosphere for which a licensed engineer has certified that the types of products stored will require constant operation at 100 percent of the design airflow. Exception 3 to Section 120.6(a)3B: Areas within refrigerated warehouses that are designed solely for the purpose of quick chilling/freezing of products, including but not limited to spaces with design cooling capacities of greater than 240 Btu/hr-ft [2] (2 tons per 100 square feet). C. Evaporator fans served by a single compressor that does not have variable capacity shall utilize controls to reduce airflow by at least 40 percent for at least 75 percent of the time when the compressor is not running.
• § 120.6 High relevance — show source text

  Exception to Section 120.6(a)2: Underslab heating systems controlled such that the electric resistance heat is thermostatically controlled and disabled during the summer on-peak period defined by the local electric utility. 3. Evaporators. New fan-powered evaporators used in coolers and freezers shall conform to the following: A. Single phase fan motors less than 1 hp and less than 460 Volts in newly installed evaporators shall be electronicallycommutated motors or shall have a minimum motor efficiency of 70 percent when rated in accordance with NEMA Standard MG 1-2006 at full load rating conditions. B. Evaporator fans served either by a suction group with multiple compressors or by a single compressor with variable capacity capability shall be variable speed and the speed shall be controlled in response to space temperature or humidity. Exception 1 to Section 120.6(a)3B: Addition, alteration or replacement of less than all of the evaporators in an existing refrigerated space that does not have speed-controlled evaporators. Exception 2 to Section 120.6(a)3B: Coolers within refrigerated warehouses that maintain a controlled atmosphere for which a licensed engineer has certified that the types of products stored will require constant operation at 100 percent of the design airflow. Exception 3 to Section 120.6(a)3B: Areas within refrigerated warehouses that are designed solely for the purpose of quick chilling/freezing of products, including but not limited to spaces with design cooling capacities of greater than 240 Btu/hr-ft [2] (2 tons per 100 square feet). C. Evaporator fans served by a single compressor that does not have variable capacity shall utilize controls to reduce airflow by at least 40 percent for at least 75 percent of the time when the compressor is not running. Exception to Section 120.6(a)3C: Areas within refrigerated warehouses that are designed solely for the purpose of quick chilling/freezing of products [space with design cooling capacities of greater than 240 Btu/hr-ft [2] (2 tons per 100 square feet)]. D. Fan-powered evaporators utilizing volatile refrigerants shall meet the applicable efficiency requirements listed in Table 120.6-A-2.

  Evaporator specific efficiency is defined as the gross total refrigeration capacity (Btu/h) divided by the electrical input power at 100 percent fan speed at rating conditions listed in Table 120.6-A-2 following the test procedure listed in Table 120.6-A-2.

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  Exception to Section 120.6(a)3D: Evaporators designed solely for the purpose of quick chilling/freezing of products, including but not limited to spaces with design cooling capacities of greater than 240 Btu/hr-ft [2] (2 tons per 100 ft [2] ). E. The applied static pressure drop for evaporators shall not exceed 0.5 in. water. Exception to Section 120.6(a)3E: Evaporators designed solely for the purpose of quick chilling/freezing of products, including but not limited to spaces with design cooling capacities of greater that 240 Btu/hr-ft [2] (2 tons per 100 ft [2] ).

• § 150.1 High relevance — show source text

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  INDEX

  150.1(c), Table 150.1-A, 150.2(b)1F, Table 150.2-D, Table 160.3-D, 160.3(c)1, 160.4(f), 170.2(c), Table 170.2-K Refrigerant Charge 120.6(b), 150.1(c)7, Table 150.1-A, 150.2(b)1F, Table 150.2-D, 170.2(c), Table 170.2-K, 180.2(b)2A Refrigerant Charge Verification 150.1(c)7, 170.2(c)3, Table 170.2-K Refrigerant Circuit 140.4(h) Refrigerated Display Case 120.6(b)3 Refrigerated Warehouse 110.2(a), 120.6(a), 120.6(a)5, 120.6(a)7, 140.3(c) Refrigerated Warehouse Insulation Table 120.6-A Refrigeration (Supermarket Systems) 140.4(e)1 Refrigeration Compressor System 120.6(b)2 Refrigeration System 120.6(a)4, 120.6(a)5, 120.6(a)7, 120.6(a)8, 120.6(b)1 Reheat 120.6(h), 120.6(j), 140.4(d), Table 140.4-A, Table 170.2-B, 170.2(c) Relamping Rated Wattage 130.0(c)1, 130.0(c)2, 160.5(b) Relative Humidity (RH) Table 140.4-G, 140.4(e)2, 170.2(c) Relief Air System 140.4(d), 170.2(c)4C Relief Fan 140.4(c)1, 170.2(c) Religious Worship Table 120.2-A, 140.6(a)3G, H, I, Table 140.6-C Relocatable Public School Building 140.3(a)8, 140.3(a)9, Table 140.3-B, Table 140.3-D, 141.0(b)3 Remote Heater 110.3(c)1 Removable Ceiling Panel 120.7(a)3 Renewable Electric Generation System 140.1(b), 150.1(b)1 Repairs 10-106(a), 141.0, 141.0(b)2A, 141.0(c), 141.0(d), 150.2(b)1B, 180.0, 180.3 Replacement Table 110.2-E, 110.3(c), 110.6(a)2, 110.6(a)3, 110.6(a)4, 110.9(c), 110.9(d), 120.6(i), 141.0(b)2C, 141.0(b)2D, 141.0(b)2E, 141.0(b)2L-R, 150.2(b)1C-I, 150.

• § 120.6 High relevance — show source text

  Exception to Section 120.6(a)4: Transcritical CO 2 refrigeration systems.

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

  TABLE 120.6-B—FAN-POWERED CONDENSERS – MINIMUM EFFICIENCY REQUIREMENTS	Col2	Col3	Col4
  CONDENSER TYPE	REFRIGERANT TYPE	MINIMUM EFFICIENCY	RATING CONDITION
  Outdoor evaporative cooled with THR Capacity > 8,000 MBH	All	350 Btuh/Watt	100°F saturated condensing temperature (SCT), 70°F outdoor wetbulb temperature
  Outdoor evaporative cooled with THR Capacity < 8,000 MBH and indoor evaporative cooled	All	160 Btuh/Watt	160 Btuh/Watt
  Outdoor air cooled	Ammonia	75 Btuh/Watt	105°F saturated condensing temperature (SCT), 95°F outdoor drybulb temperature
  Outdoor air cooled	Halocarbon	65 Btuh/Watt	65 Btuh/Watt
  Adiabatic dry mode	Halocarbon	45 Btuh/Watt	105°F saturated condensing temperature (SCT), 95°F outdoor drybulb temperature
  Indoor air cooled	All	No requirement	No requirement

  5. Compressors. Compressor systems utilized in refrigerated warehouses shall conform to the following: A. Compressors serving refrigeration systems that are not transcritical CO 2 shall be designed to operate at a minimum condensing temperature of 70°F or less. B. Compressors for transcritical CO 2 refrigeration systems shall be designed to operate at a minimum condensing temperature of 60°F or less. Exception to Section 120.6(a)5B: Compressors with a design saturated suction temperature greater than or equal to 30°F shall be designed to operate at a minimum condensing temperature of 70°F or less. C. New open-drive screw compressors in new refrigeration systems with a design saturated suction temperature (SST) of 28°F or lower that discharges to the system condenser pressure shall control compressor speed in response to the refrigeration load. Exception 1 to Section 120.6(a)5C: Refrigeration plants with more than one dedicated compressor per suction

  group. Exception 2 to Section 120.6(a)5C: Compressors and condensers on a refrigeration system for which more than 20 percent of the total design refrigeration cooling load is for quick chilling/ freezing of products [space with design cooling capacities of greater than 240 Btu/hr-ft [2] (2 tons per 100 ft [2] )], or process refrigeration cooling for other than a refrigerated space. D. New screw compressors with nominal electric motor power greater than 150 HP shall include the ability to automatically vary the compressor volume ratio (Vi) in response to operating pressures. 6. Infiltration barriers. Passageways between freezers and higher-temperature spaces, and passageways between coolers and nonrefrigerated spaces, shall have an infiltration barrier consisting of strip curtains, an automaticallyclosing door or an air curtain designed by the manufacturer for use in the passageway and temperature for which it is applied.

• § 0.110. High relevance — show source text

  C. Wood framed and others. A minimum of R-11 insulation between framing members, or the area-weighted average U- factor of the wall assembly shall not exceed U-0.110. D. Spandrel panels and curtain walls. A minimum of R-4, or the area-weighted average U- factor of the wall assembly shall not exceed U-0.280.

  Exception to Section 180.2(a)2: Light and heavy mass walls. 3. Floor insulation. For the altered portion of raised floors that separate conditioned spaces from unconditioned spaces or ambient air shall meet the applicable requirements of Items A and B below: A. Raised framed floors. A minimum of R-11 insulation between framing members, or the area-weighted average U- factor of the floor assembly shall not exceed U-0.071. B. Raised mass floors. A minimum of R-6 insulation, or the area-weighted average U- factor of the floor assembly shall not exceed U-0.111.

  (b) Prescriptive approach. The altered component and any newly installed equipment serving the alteration shall meet the applicable requirements of Sections 110.0 through 110.9 and all applicable requirements of Sections 160.0, 160.1, 160.2(c) and (d), 160.3(a) through 160.3(b)5J, 160.3(b)6, 160.3(c) and 160.5; and

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  MULTIFAMILY BUILDINGS—ADDITIONS, ALTERATIONS AND REPAIRS TO EXISTING MULTIFAMILY BUILDINGS

  1. Envelope. A. Roof alterations . Existing roofs being replaced, recovered or recoated of a multifamily building shall meet the requirements of Section 110.8(i). For roofs with more than 50 percent of the roof area or more than 2,000 square feet of roof, whichever is less, being altered, the requirements of i through iii below apply: i. Low-sloped roofs in Climate Zones 2, 4, and 6 through 15 shall have a minimum aged solar reflectance of 0.63 and a minimum thermal emittance of 0.75, or a minimum SRI of 75. Exception to Section 180.2(b)1Ai: The aged solar reflectance requirement can be met by using insulation at the roof deck specified in Table 180.2-A.

  TABLE 180.2-A—ROOF/CEILING INSULATION TRADEOFF FOR LOW-SLOPED AGED SOLAR REFLECTANCE	Col2	Col3
  MINIMUM AGED SOLAR REFLECTANCE	ROOF DECK CONTINUOUS INSULATIONR- VALUE (Climate Zones 6–7)	ROOF DECK CONTINUOUS INSULATION_R-_VALUE (Climate Zones 2, 4, 8–15)
  0.60	2	16
  0.55	4	18
  0.50	6	20
  0.45	8	22
  No requirement	10	24

  ii. Steep-sloped roofs in Climate Zones 4 and 8 through 15 shall have a minimum aged solar reflectance of 0.20 and a minimum thermal emittance of 0.75, or a minimum SRI of 16.

• § 140.8 High relevance — show source text

  5(d), 140.8(b), Table 140.9-B, 141.1(b), 160.5(b), 170.2(d) Supply efficiency 140.8(b)3, 140.8(b)5, 170.2(d) Trade-offs 140.7(b), 170.2(d) Venting 110.2(d), 110.2(f) PPM 120.1(d), 120.6(c), 160.2(c) Pre-Cooling 170.1(d) Precooling Coils 140.4(e)3, 170.2(c) Preexisting Energy Consumption 141.0(c), 180.3 Pre-Occupancy 120.1(d), 160.2(c)5 Precision Commercial and Industrial Work 140.6(b)4 Prescriptive Compliance Approach 140.0, 140.1, 140.2, 140.0(c), 141.0(a)1, 141.0(b)2, 150.1, 150.2(a)1, 150.2(b)1, 170.2, 180.0, 180.1(a), 180.2(b) Requirements 140.1, 140.3, 140.4, 140.5, 140.6, 140.7, 140.8, 140.9, 140.9(b), 140.9(c), 140.10, 170.1(a),

  170.2 Standards 110.1(b), 110.1(c), 150.1(a), 150.1(c), 170.0, 170.2 Prescriptive Ventilation System Duct Sizing

  [ASHRAE 62.2: Table 5-3] Table 150.0-H, Table 160.2-H Prescriptive Envelope Criteria for Guest Rooms of Hotel/Motel Buildings Table 140.3-C

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  INDEX

  150.1(c), Table 150.1-A, 150.2(b)1F, Table 150.2-D, Table 160.3-D, 160.3(c)1, 160.4(f), 170.2(c), Table 170.2-K Refrigerant Charge 120.6(b), 150.1(c)7, Table 150.1-A, 150.2(b)1F, Table 150.2-D, 170.2(c), Table 170.2-K, 180.2(b)2A Refrigerant Charge Verification 150.1(c)7, 170.2(c)3, Table 170.2-K Refrigerant Circuit 140.4(h) Refrigerated Display Case 120.6(b)3 Refrigerated Warehouse 110.2(a), 120.6(a), 120.6(a)5, 120.6(a)7, 140.3(c) Refrigerated Warehouse Insulation Table 120.6-A Refrigeration (Supermarket Systems) 140.4(e)1 Refrigeration Compressor System 120.6(b)2 Refrigeration System 120.6(a)4, 120.6(a)5, 120.

• § 1217.8.4 Medium relevance — show source text

  (2) Plastic tube/cable ties, typically nylon, fastened to anchors such as rebar or wire mesh.

  (3) Staples made of metal or plastic or combination thereof, without sharp edges that would harm tube, fastened to insulation or subfloor.

  (4) Plastic rails with integrated tube holders intended for the specific type of tube.

  (5) Insulation sheets with integrated knobs for holding the specific type of tube and intended for this application.

  (6) Other fasteners recommended by the manufacturer. 1217.8.4 Spacing of Tube Fasteners. The maximum spacing between tube fasteners within a concrete floor shall not exceed the spacing specified by the manufacturer or, in the absence of manufacturer’s specifications, 2.5 feet (762 mm). 1217.9 Joist Systems and Subfloors. Where tubing is installed below a subfloor, the tube spacing shall be in accordance with the system design and joist space limitations.

  Where tubing is installed above or in the subfloor, the tube spacing shall not exceed 12 inches (305 mm) center-tocenter for living areas.

  Where tubing is installed in the joist cavity, the cavity shall be insulated with not less than R-12 material below the heated space.

  An air space of not less than 1 inch (25.4 mm) and not more than 3 inches (76 mm) shall be maintained between the top of the insulation and the underside of the floor unless a conductive plate is installed in accordance with manufacturer’s instructions.

  Where tubing is installed in panels above or in the subfloor and not embedded in concrete, the floor assembly shall be insulated with not less than R-5 material below the tubing when installed over habitable space.

  1217.9.1 Tubing Fasteners. Tubing that is installed within joist spaces and subfloor panel systems shall be fastened according to manufacturer’s instructions. Unless prohibited by the manufacturer, tubing fasteners shall include the following:

  (1) Heat transfer panel systems made of wood, aluminum or other thermally conductive materials intended for this application and the specific type of tube.

  (2) Staples made of metal or plastic or combination thereof, without sharp edges that would harm tube. intended for this application and the specific type of tube fastened to subfloor.

  (3) Plastic rails with integrated tube holders intended for the specific type of tube.

  (4) Other fasteners recommended by the manufacturer. 1217.10 Wall and Ceiling Panels. Where radiant tubing is installed in the stud wall cavity or the ceiling joist cavity, the cavity shall be insulated with not less than R-12 material. The insulation shall be installed in such a manner as to prevent heating or cooling loss from the space intended to be controlled.

  An air space of not less than 1 inch (25.4 mm) and not more than 3 inches (76 mm) shall be maintained between the insulation and the interior surface of the panel unless a conductive plate is installed.

  1217.10.1 California Energy Code Pipe Insulation Requirements. See California Energy Code Sections 150.0(j)2 and 120.3(c) for pipe insulation requirements based on fluid temperature and pipe diameter – where California Energy Code Table 120.3-A-1 or Table 120.3- A-2 specifies insulation greater than R- 12, the higher value is required.

• § 11.7 Medium relevance — show source text

  (3) The individual mechanical cooling unit has a design cooling capacity of not more than 40 000

  434 2025 CALIFORNIA MECHANICAL CODE

  ), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

  APPENDIX E

  Btu/h (11.7 kW). An individual mechanical cooling unit is a single system composed of a fan or fans and a cooling coil capable of providing mechanical cooling.

  (4) Systems serving spaces where specific humidity levels are required to satisfy process application needs, such as vivariums, museums, surgical suites, pharmacies, and buildings with refrigerating systems, such as supermarkets, refrigerated warehouses, and ice arenas, and where the building includes site-recovered energy or on-site renewable energy that provide energy equal to 75 percent or more of the annual energy for reheating or for providing warm air in mixing systems. This exception shall not apply to computer rooms.

  (5) Not less than 90 percent of the annual energy for reheating or for providing warm air in mixing systems is provided from site-recovered energy (including condenser heat) or on-site renewable energy.

  (6) Systems where the heat added to the airstream is the result of the use of a desiccant system and 75 percent of the heat added by the desiccant system is removed by a heat exchanger, either before or after the desiccant system with energy recovery. [ASHRAE 90.1:6.5.2.3]

  E 503.5.5.4 Humidifier Preheat. Humidifiers

  with preheating jackets mounted in the airstream shall be provided with an automatic valve to shut off preheat where humidification is not required.

  [ASHRAE 90.1:6.5.2.4.1]

  E 503.5.5.4.1 Insulation. Humidification system dispersion tube hot surfaces in the airstreams of ducts or air-handling units shall be insulated with a product with an insulating value of not less than R-0.5.

  Exception: Systems where mechanical cooling, including economizer operation, does not occur

  simultaneously with humidification. [ASHRAE 90.1:6.5.2.4.2]

  E 503.5.5.5 Preheat Coils. Preheat coils shall have controls that stop their heat output where mechanical cooling, including economizer operation, is occurring. [ASHRAE 90.1:6.5.2.5]

  E 503.5.5.6 Ventilation Air Heating Control. Units that provide ventilation air to multiple zones and operate in conjunction with zone heating and cooling systems shall not use heating or heat recovery to warm supply air above 60°F (16°C) when representative building loads or outdoor air temperature indicate that the majority of zones require cooling.

  Exception: Units that heat the airstream using only series energy recovery when representative building loads or outdoor air temperature indicate that the majority of zones require cooling in Climate Zones 0A, 1A, 2A, 3A, and 4A. [ASHRAE 90.1:6.5.2.6]

• § 1.9 Medium relevance — show source text

  9| |7 to 8|R-1.9|R-1.9|R-1.9|

  Notes: 1 Insulation R-values, measured in [°F•h•ft 2 /(Btu•in)] [(m•K)/W], are for the insulation as installed and do not include film resistance. The required minimum thicknesses do not consider water vapor transmission and possible surface condensation. Where portions of the building envelope are used as a plenum enclosure, building envelope insulation shall be as required by the most restrictive condition of Section E 503.4.7.1 or ASHRAE 90.1, depending on whether the plenum is located in the roof, wall, or floor. Insulation resistance measured on a horizontal plane in accordance with ASTM C518 at a mean temperature of 75°F (24°C) at the installed thickness. 2 Includes attics above insulated ceilings, parking garages and crawl spaces. 3 Includes return air plenums, with or without exposed roofs above. 4 Return ducts in this duct location do not require insulation.

  TABLE E 503.7.3(1) MINIMUM PIPE INSULATION THICKNESS FOR HEATING AND HOT WATER SYSTEMS [1, 2, 3, 4, 5]

  (STEAM, STEAM CONDENSATE, HOT WATER HEATING, AND DOMESTIC WATER SYSTEMS)

  [ASHRAE 90.1: TABLE 6.8.3-1]

  FLUID OPERATING TEMPERATURE RANGE (F°) AND USAGE	INSULATION CONDUCTIVITY	Col3	NOMINAL PIPE SIZE OR TUBE SIZE (inches)	Col5	Col6	Col7	Col8
  FLUID OPERATING TEMPERATURE RANGE (F°) AND USAGE	CONDUCTIVITY Btu•inch/(h•ft2•°F)	MEAN RATING TEMPERATURE °F	<1	1 to <11_/_2	11_/_2 to <4	4 to <8	≥8
  FLUID OPERATING TEMPERATURE RANGE (F°) AND USAGE	CONDUCTIVITY Btu•inch/(h•ft2•°F)	MEAN RATING TEMPERATURE °F	INSULATION THICKNESS (inches)	INSULATION THICKNESS (inches)	INSULATION THICKNESS (inches)	INSULATION THICKNESS (inches)	INSULATION THICKNESS (inches)
  >350	0.32 to 0.34	250	4.5	5.0	5.0	5.0	5.0
  251 to 350	0.29 to 0.32	200	3.0	4.0	4.5	4.5	4.5
  201 to 250	0.27 to 0.30	150	2.5	2.5	2.5	3.0	3.0
  141 to 200	0.25 to 0.29	125	1.5	1.5	2.0	2.0	2.0
  105 to 140	0.22 to 0.28	100	1.

• § 0.32 Medium relevance — show source text

  22| |Fenestration – Operable Windows|Minimum VT|0.32| |Fenestration – Glazed Doors
  (Site-Built and Factory Assembled)|Maximum U-factor|0.45| |Fenestration – Glazed Doors
  (Site-Built and Factory Assembled)|Maximum RSHGC|0.23| |Fenestration – Glazed Doors
  (Site-Built and Factory Assembled)|Minimum VT|0.17| |Fenestration – Skylights|Maximum U-factor|See Table 140.3-B| |Fenestration – Skylights|Maximum RSHGC|See Table 140.3-B| |Fenestration – Skylights|Minimum VT|See Table 140.3-B| |Fenestration – Skylights|Maximum SRR|5%| |Exterior Doors – Non-Swinging doors|Maximum U-factor|0.50| |Exterior Doors – Swinging doors|Maximum U-factor|0.70|

  (b) Reserved.

  (c) Minimum daylighting requirement for large enclosed spaces. In climate zones 2 through 15, conditioned enclosed spaces, and unconditioned enclosed spaces that are greater than 5,000 square feet and that are directly under a roof with ceiling heights greater than 15 feet, shall meet the following requirements:

  1. A combined total of at least 75 percent of the floor area, as determined in building floor plan (drawings) view, shall be within one or more of the following: A. Primary sidelit daylit zone in accordance with Section 130.1(d), or B. The total floor area in the space within a horizontal distance of 0.7 times the average ceiling height from the edge of rough opening of skylights.
  2. All skylit daylit zones and primary sidelit daylit zones shall be shown on building plans.
  3. General lighting in daylit zones shall be controlled in accordance with Section 130.1(d).
  4. The total skylight area is at least 3 percent of the total floor area in the space within a horizontal distance of 0.7 times the average ceiling height from the edge of rough opening of skylights; or the product of the total skylight area and the average skylight visible transmittance is no less than 1.5 percent of the total floor area in the space within a horizontal distance of 0.7 times the average ceiling height from the edge of rough opening of skylights.

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  NONRESIDENTIAL AND HOTEL/MOTEL OCCUPANCIES—PERFORMANCE AND PRESCRIPTIVE

  COMPLIANCE APPROACHES FOR ACHIEVING ENERGY EFFICIENCY

  5. All skylights shall have a glazing material or diffuser that has a measured haze value greater than 90 percent, tested according to ASTM D1003 (notwithstanding its scope) or other test method approved by the Commission.
  6. Skylights for conditioned and unconditioned spaces shall have an area-weighted average visible transmittance (VT) no less than the applicable value required by Section 140.3(a)6D.

  Exception 1 to Section 140.3(c): Auditoriums, churches, movie theaters, museums and refrigerated warehouses.

• § 10-109 Medium relevance — show source text

  PROPOSED DESIGN BUILDING is a building that is simulated by Commission-approved compliance software to determine the energy consumption resulting from all of the characteristics and energy consuming features that are actually proposed for a building, as specified by Section 10-109(c) and Section 10-116.

  PUBLIC AREAS are spaces generally open to the public at large, customers or congregation members, or similar spaces where occupants need to be prevented from controlling lights for safety, security or business reasons. R -VALUE is the measure of the thermal resistance of insulation or any material or building component expressed in ft [2] -hr-°F/Btu.

  RADIANT BARRIER is a highly reflective, low emitting material installed at the underside surface of the roof deck and the inside surface of gable ends or other exterior vertical surfaces in attics to reduce solar heat gain.

  RAISED FLOOR is a floor (partition) over a crawl space, or an unconditioned space, or ambient air.

  READILY ACCESSIBLE is capable of being reached quickly for operation, repair or inspection, without requiring climbing or removing obstacles, or resorting to access equipment.

  RECOOL is the cooling of air that has been previously heated by space-conditioning equipment or systems serving the same building.

  RECOVERED ENERGY is energy used in a building that (1) is recovered from space conditioning, service water heating, lighting, or process equipment after the energy has performed its original function; (2) provides space conditioning, service water heating, or lighting; and (3) would otherwise be wasted.

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  ALL OCCUPANCIES—GENERAL PROVISIONS

  RECOVERED ENERGY, ON-SITE is recovered energy that is captured at the building site.

  REFERENCE APPENDICES is the support document for the Building Energy Efficiency Standards. The document consists of three sections: the Reference Joint Appendices (JA), the Reference Residential Appendices (RA) and the Reference Nonresidential Appendices (NA).

  REFLECTANCE, SOLAR is the ratio of the reflected solar flux to the incident solar flux.

  REFRIGERATED CASE is a manufactured commercial refrigerator or freezer, including but not limited to display cases, reach-in cabinets, meat cases, and frozen food and soda fountain units.

  REFRIGERATED SPACE is a space constructed for storage or handling of products, where mechanical refrigeration is used to maintain the space temperature at 55°F or less.

  REFRIGERATED WAREHOUSE is a building or a space greater than or equal to 3,000 square feet constructed for storage or handling of products, where mechanical refrigeration is used to maintain the space temperature at 55°F or less.

  REHEAT is the heating of air that has been previously cooled by cooling equipment or supplied by an economizer.

  RELOCATABLE PUBLIC SCHOOL BUILDING is a relocatable building as defined by Title 24, Part 1, Section 4-314, which is subject to Title 24, Part 1, Chapter 4, Group 1.

  REPAIR is the reconstruction or renewal for the purpose of maintenance of any component, system or equipment of an existing building. Repairs shall not increase the preexisting energy consumption of the repaired component, system or equipment. Replacement of any component, system or equipment for which there are requirements in the Standards is considered an alteration and not a repair.