Roof insulation, reroofing rules, and rooftop structures

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

• CBC § 1508.2 High relevance — show source text

  [BF] 1508.2 Material standards. Above-deck thermal insulation board shall comply with the standards in Table 1508.2.

  [BF] TABLE 1508.2—MATERIAL STANDARDS FOR ROOF INSULATION	Col2
  MATERIAL	STANDARD
  Cellular glass board	ASTM C552 or ASTM C1902
  Composite boards	ASTM C1289, Type III, IV, V or VII
  Expanded polystyrene	ASTM C578
  Extruded polystyrene	ASTM C578
  Fiber-reinforced gypsum board	ASTM C1278
  Glass-faced gypsum board	ASTM C1177
  High-density polyisocyanurate board	ASTM C1289, Type II, Class 4
  Mineral fiber insulation board	ASTM C726
  Perlite board	ASTM C728
  Polyisocyanurate board	ASTM C1289, Type I or II
  Wood fiberboard	ASTM C208, Type II

  SECTION 1509—ROOF COATINGS

  1509.1 General. The installation of a roof coating on a roof covering shall comply with the requirements of Section 1505 and this section.

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  ROOF ASSEMBLIES AND ROOFTOP STRUCTURES

  1509.2 Material standards. Roof coating materials shall comply with the standards in Table 1509.2.

  TABLE 1509.2—ROOF COATING MATERIAL STANDARDS	Col2
  MATERIAL	STANDARD
  Acrylic coating	ASTM D6083
  Asphaltic emulsion coating	ASTM D1227
  Asphalt coating	ASTM D2823
  Asphalt roof coating	ASTM D4479
  Aluminum-pigmented asphalt coating	ASTM D2824
  Silicone coating	ASTM D6694
  Moisture-cured polyurethane coating	ASTM D6947

  SECTION 1510—RADIANT BARRIERS INSTALLED ABOVE DECK

  [BF] 1510.1 General. A radiant barrier installed above a deck shall comply with Sections 1510.2 through 1510.4.

  [BF] 1510.2 Fire testing. Radiant barriers shall be permitted for use above decks where the radiant barrier is covered with an approved roof covering and the system consisting of the radiant barrier and the roof covering complies with the requirements of either FM 4450 or UL 1256.

  [BF] 1510.3 Installation. The low emittance surface of the radiant barrier shall face the continuous airspace between the radiant barrier and the roof covering.

  [BF] 1510.4 Material standards. A radiant barrier installed above a deck shall comply with ASTM C1313/C1313M.

  SECTION 1511—ROOFTOP STRUCTURES

  [BG] 1511.1 General. The provisions of this section shall govern the construction of rooftop structures.

• CBC § 15-20 High relevance — show source text

  1508 Roof Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15-20

  1509 Roof Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15-20

  1510 Radiant Barriers Installed Above Deck . . . . . . . . . .15-21

  1511 Rooftop Structures . . . . . . . . . . . . . . . . . . . . . . . . . . .15-21

  1512 Reroofing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15-24

  1513 [DSA-SS & DSA-SS/CC, OSHPD 1, 1R, 2, 4 & 5] Seismic Anchorage of Slate Shingle, Clay and Concrete Tile Roof Coverings. . . . . . . 15-25

  INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . INDEX-1

  HISTORY NOTE TO VOLUME 1 . . . . . . . . . . . . . . . . . . . . . .HIST-1

  VOLUME 2

  CHAPTER 16 STRUCTURAL DESIGN . . . . . . . . . . . . . . . . . .16-1

  1601 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-3

  1602 Notations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-3

  1603 Construction Documents . . . . . . . . . . . . . . . . . . . . . . . 16-4

  1604 General Design Requirements. . . . . . . . . . . . . . . . . . . 16-5

  1605 Load Combinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-8

  1606 Dead Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-9

  1607 Live Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16-10

  1608 Snow Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16-18

  1609 Wind Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16-24

  1610 Soil Loads and Hydrostatic Pressure. . . . . . . . . . . .16-31

• CBC § 14-23 High relevance — show source text

  1413 [DSA-SS & DSA-SS/CC, OSHPD 1, 1R, 2, 4 & 5] Additional Requirements for Anchored and Adhered Veneer. . . . . . . . . . . . . . 14-23

  CHAPTER 15 ROOF ASSEMBLIES AND ROOFTOP

  STRUCTURES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-1

  1501 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-3

  1502 Roof Drainage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-3

  1503 Weather Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-3

  1504 Performance Requirements . . . . . . . . . . . . . . . . . . . . 15-3

  1505 Fire Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-5

  1506 Materials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-6

  1507 Requirements for Roof Coverings . . . . . . . . . . . . . . . 15-7

  1508 Roof Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15-20

  1509 Roof Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15-20

  1510 Radiant Barriers Installed Above Deck . . . . . . . . . .15-21

  1511 Rooftop Structures . . . . . . . . . . . . . . . . . . . . . . . . . . .15-21

  1512 Reroofing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15-24

  1513 [DSA-SS & DSA-SS/CC, OSHPD 1, 1R, 2, 4 & 5] Seismic Anchorage of Slate Shingle, Clay and Concrete Tile Roof Coverings. . . . . . . 15-25

  INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . INDEX-1

  HISTORY NOTE TO VOLUME 1 . . . . . . . . . . . . . . . . . . . . . .HIST-1

  VOLUME 2

  CHAPTER 16 STRUCTURAL DESIGN . . . . . . . . . . . . . . . . . .16-1

• CBC § 1502.2 High relevance — show source text

  1||||X|X|||||||||||||||||||| |1502.2||||X|X|||||||||||||||||||| |1503.3 – 1503.4|||X|||||||||||||||||||||| |1505 – 1507|||X|||||||||||||||||||||| |1507.3.10||||||||X|X|X|X|X||X|X|||||||||| |1507.7.8||||||||X|X|X|X|X||X|X|||||||||| |1509 – 1511|||X|||||||||||||||||||||| |1511.9.6||||||X|X|||||||||||||||||| |1511.10– 1511.10.1|X|||X|X|||X|X|X|X|X||X|X|||||||||| |1512|||X|||||||||||||||||||||| |1513||||||||X|X|X|X|X||X|X||||||||||

  The state agency does not adopt sections identified by the following symbol:

  The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.

  2025 CALIFORNIA BUILDING CODE 15-1

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  15-2 2025 CALIFORNIA BUILDING CODE

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  15 ROOF ASSEMBLIES AND ROOFTOP STRUCTURES

  User notes:

  About this chapter: Chapter 15 provides minimum requirements for the design and construction of roof assemblies and rooftop structures. The criteria address the weather-protective barrier at the roof and, in most circumstances, a fire-resistant barrier. The chapter is largely prescriptive in nature and is based on decades of experience with various traditional materials, but it also recognizes newer products. Section 1511 addresses rooftop structures, which include penthouses, tanks, towers and spires. Rooftop penthouses larger than prescribed in this chapter must be treated as a story under Chapter 5.

  ICC code development note: Code change proposals to sections preceded by the designation [BF] or [P] will be considered by one of the code development committees meeting during the 2024 (Group A) Code Development Cycle. All other code change proposals will be considered by a code development committee meeting during the 2025 (Group B) Code Development Cycle.

  SECTION 1501—GENERAL

  1501.1 Scope. The provisions of this chapter shall govern the design, materials, construction and quality of roof assemblies, and rooftop structures.

  SECTION 1502—ROOF DRAINAGE

  [P] 1502.1 General. Design and installation of roof drainage systems shall comply with this section, Section 1611 of this code and Chapter 11 of the California Plumbing Code .

  [P] 1502.2 Secondary (emergency overflow) drains or scuppers. Where roof drains are required, secondary (emergency overflow) roof drains or scuppers shall be provided where the roof perimeter construction extends above the roof in such a manner that water will be entrapped if the primary drains allow buildup for any reason. The installation and sizing of secondary emergency overflow drains, leaders and conductors shall comply with Section 1611 of this code and Chapter 11 of the California Plumbing Code .

• CBC § 9-4 High relevance — show source text

  R904 Materials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4

  R905 Requirements for Roof Coverings . . . . . . . . . . . . . . . . 9-4

  R906 Roof Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-19

  R907 Rooftop-Mounted Photovoltaic Panel Systems . . . 9-19

  R908 Reroofing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-19

  R909 Roof Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-20

  CHAPTER 10 CHIMNEYS AND FIREPLACES . . . . . . . . . . . .10-3

  R1001 Masonry Fireplaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3

  R1002 Masonry Heaters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6

  R1003 Masonry Chimneys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-7

  R1004 Factory-Built Fireplaces. . . . . . . . . . . . . . . . . . . . . . . . 10-12

  R1005 Factory-Built Chimneys . . . . . . . . . . . . . . . . . . . . . . . . 10-12

  R1006 Exterior Air Supply. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-12

  Part IV—Energy Conservation. . . . . . . . . . . . . . . . . . . . . . . .11-1

  Part V—Mechanical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12-1

  Part VI—Fuel Gas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24-1

  Part VII—Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25-1

  Part VIII—Electrical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34-1

  Part IX— Referenced Standards . . . . . . . . . . . . . . . . . . . . . .44-3

  CHAPTER 44 REFERENCED STANDARDS . . . . . . . . . . . . . .44-3

• CBC § 1507.17.4.2 High relevance — show source text

  Exception: As an alternative, adhered underlayment complying with ASTM D1970 shall be permitted.

  1507.17.4.2 Ice barrier. In areas where there has been a history of ice forming along the eaves causing a back-up of water, an ice barrier consisting of not fewer than two layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet shall be used instead of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building.

  Exception: Detached accessory structures that do not contain conditioned floor area.

  1507.17.5 Material standards. BIPV roof panels shall be listed and labeled in accordance with UL 7103.

  1507.17.6 Attachment. BIPV roof panels shall be attached in accordance with the manufacturer’s installation instructions.

  1507.17.7 Flashing. Flashing for BIPV roof panels shall be installed in accordance with the roof covering manufacturer’s installation instructions to prevent water from entering the wall and roof through joints in copings, through moisture-permeable materials and at intersections with parapet walls and other penetrations through the roof plane.

  SECTION 1508—ROOF INSULATION

  [BF] 1508.1 General. The use of above-deck thermal insulation shall be permitted provided that such insulation is covered with an approved roof covering and passes the tests of NFPA 276 or UL 1256 when tested as an assembly.

  Exceptions:

  1. Foam plastic roof insulation shall conform to the material and installation requirements of Chapter 26.
  2. Where a concrete or composite metal and concrete roof deck is used and the above-deck thermal insulation is covered with an approved roof covering.

  [BF] 1508.2 Material standards. Above-deck thermal insulation board shall comply with the standards in Table 1508.2.

  [BF] TABLE 1508.2—MATERIAL STANDARDS FOR ROOF INSULATION	Col2
  MATERIAL	STANDARD
  Cellular glass board	ASTM C552 or ASTM C1902
  Composite boards	ASTM C1289, Type III, IV, V or VII
  Expanded polystyrene	ASTM C578
  Extruded polystyrene	ASTM C578
  Fiber-reinforced gypsum board	ASTM C1278
  Glass-faced gypsum board	ASTM C1177
  High-density polyisocyanurate board	ASTM C1289, Type II, Class 4
  Mineral fiber insulation board	ASTM C726
  Perlite board	ASTM C728
  Polyisocyanurate board	ASTM C1289, Type I or II
  Wood fiberboard	ASTM C208, Type II

  SECTION 1509—ROOF COATINGS

  1509.1 General. The installation of a roof coating on a roof covering shall comply with the requirements of Section 1505 and this section.

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  ROOF ASSEMBLIES AND ROOFTOP STRUCTURES

  1509.2 Material standards. Roof coating materials shall comply with the standards in Table 1509.2.

• CBC § 8-3 High relevance — show source text

  R802 Wood Roof Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3

  R803 Roof Sheathing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-30

  R804 Cold-Formed Steel Roof Framing . . . . . . . . . . . . . . . 8-31

  R805 Ceiling Finishes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-44

  R806 Roof Ventilation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-44

  R807 Attic Access. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-46

  CHAPTER 9 ROOF ASSEMBLIES . . . . . . . . . . . . . . . . . . . . . .9-3

  R901 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3

  R902 Fire Classification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3

  R903 Weather Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4

  R904 Materials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4

  R905 Requirements for Roof Coverings . . . . . . . . . . . . . . . . 9-4

  R906 Roof Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-19

  R907 Rooftop-Mounted Photovoltaic Panel Systems . . . 9-19

  R908 Reroofing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-19

  R909 Roof Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-20

  CHAPTER 10 CHIMNEYS AND FIREPLACES . . . . . . . . . . . .10-3

  R1001 Masonry Fireplaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3

  R1002 Masonry Heaters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-6

  R1003 Masonry Chimneys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-7

• CBC § 16.6 High relevance — show source text

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

  ROOF ASSEMBLIES

  R905.16.6 Attachment. BIPV roof panels shall be attached in accordance with the manufacturer’s installation instructions.

  R905.16.7 Wind resistance of BIPV roof panels. BIPV roof panels shall be tested in accordance with UL 7103 and installed to resist the component and cladding loads specified in Table R301.2.1(1), adjusted for height and exposure in accordance with Table R301.2.1(2).

  SECTION R906—ROOF INSULATION

  R906.1 General. Where above-deck thermal insulation is installed, such insulation shall be covered with an approved roof covering and shall comply with NFPA 276 or UL 1256.

  R906.2 Material standards. Above-deck thermal insulation board shall comply with the standards in Table R906.2.

  TABLE R906.2—MATERIAL STANDARDS FOR ROOF INSULATION	Col2
  MATERIAL	STANDARD
  Cellular glass board	ASTM C552or ASTM C1902
  Composite boards	ASTM C1289, Type III, IV, V or VI
  Expanded polystyrene	ASTM C578
  Extruded polystyrene board	ASTM C578
  Fiber-reinforced gypsum board	ASTM C1278
  Glass-faced gypsum board	ASTM C1177
  Mineral wool board	ASTM C726
  Perlite board	ASTM C728
  Polyisocyanurate board	ASTM C1289, Type I or II
  Wood fiberboard	ASTM C208

  SECTION R907—ROOFTOP-MOUNTED PHOTOVOLTAIC PANEL SYSTEMS

  R907.1 Rooftop-mounted (PV) photovoltaic panel systems. Rooftop-mounted photovoltaic panel systems shall be designed and installed in accordance with Section R329 and the California Electrical Code .

  R907.2 Fire classification. Rooftop-mounted photovoltaic panel systems shall have the fire classification as required by Section R902.4.

  R907.3 Installation. Rooftop-mounted photovoltaic panel systems shall be installed in accordance with the manufacturer’s installation instructions.

  R907.4 Photovoltaic panels and modules. Photovoltaic panel systems mounted on top of a roof shall be listed and labeled in accor- dance with UL 2703 and shall be installed in accordance with the manufacturer’s installation instructions.

  R907.5 Fire safety provisions for photovoltaic panel system. Solar photovoltaic panel systems installed upon a roof or as an integral part of a roof assembly shall comply with the requirements of this code and the California Fire Code.

  SECTION R908—REROOFING

  R908.1 General. Materials and methods of application used for recovering or replacing an existing roof covering shall comply with the requirements of this chapter.

• CBC § 3111.1.2 High relevance — show source text

  3111.1.2

  Materials Chapter 6 Penetration of fire-resistant assemblies

  714 Protection from adjacent construction 3307.1

  Rain loads 1611

  Roof deck 1609.6.1 Signs, roof mounted H110 Slope, minimum Chapter 15

  Snow load 1608 Solar systems, rooftop-mounted 3111.1, 3111.3.2 Trusses 2206.1.3, 2303.4, 2308.11.12 Ventilation 1202.2

  Wood (see Roof Construction, Wood) Roof Construction, Wood 602.4, 602.5 Anchorage to walls 1604.8.2 Attic access 1209.2 Ceiling joists 2308.11.1 Diaphragms 2305.1, 2306.2 Fastening requirements 2304.10 Fire-retardant-treated Table 601,

  603.1

  Framing 2304.11.4, 2308.11 Rafters 2306.1.1, 2308.11.2 Sheathing 2304.8.2, 2308.11.9 Trusses 2303.4, 2308.11.12 Ventilation, attic 1202.2 Wind uplift 2308.11.4 Roof Coverings 1507 Asphalt shingles 1507.2, 1609.2.1 Built up 1507.10 Clay tile 1507.3, 1513 Concrete tile 1507.3, 1513 Fire district D102.2.4

  Fire resistance 603.1, 1505 Flashing 1503.2, 1503.5, 1507.2.8, 1507.3.9, 1507.5.7, 1507.7.7, 1507.8.8, 1507.9.9 Impact resistance 1504.7 Insulation 1508 Liquid-applied coating 1507.14 Membrane 3102 Metal roof panels 1507.4 Metal roof shingles 1507.5 Modified bitumen 1507.11 Photovoltaic roof panels, buildingintegrated 1507.17 Photovoltaic shingles 1507.16 Plastics, light-transmitting panels 2609 Reroofing 1512 Roll 1507.6

  Roof recover 1512.3 Roof replacement 1512.2 Single-ply membrane 1507.12 Slate shingles 1504.4.4, 1507.7, 1513 Sprayed polyurethane foam 1507.13 Thermoplastic single-ply 1507.13 Wind loads 1504.1, 1609.6 Wood shakes 1507.9 Wood shingles 1507.8 Roof Deck 1609.6.1 Roof Drainage 1502 Scuppers 1502.2 Room Dimensions 1209 Rooming House (see Boarding House) 310 Safeguards During Construction Chapter 33 Accessibility Chapters 11A and 11B Adjoining property protection 3307 Construction 3302

  Demolition 3303

  Excavations 1804.1 Fire extinguishers 3309 Fire watch 3314

• CBC § 4.1 High relevance — show source text

  SECTION R907—ROOFTOP-MOUNTED PHOTOVOLTAIC PANEL SYSTEMS

  R907.1 Rooftop-mounted (PV) photovoltaic panel systems. Rooftop-mounted photovoltaic panel systems shall be designed and installed in accordance with Section R329 and the California Electrical Code .

  R907.2 Fire classification. Rooftop-mounted photovoltaic panel systems shall have the fire classification as required by Section R902.4.

  R907.3 Installation. Rooftop-mounted photovoltaic panel systems shall be installed in accordance with the manufacturer’s installation instructions.

  R907.4 Photovoltaic panels and modules. Photovoltaic panel systems mounted on top of a roof shall be listed and labeled in accor- dance with UL 2703 and shall be installed in accordance with the manufacturer’s installation instructions.

  R907.5 Fire safety provisions for photovoltaic panel system. Solar photovoltaic panel systems installed upon a roof or as an integral part of a roof assembly shall comply with the requirements of this code and the California Fire Code.

  SECTION R908—REROOFING

  R908.1 General. Materials and methods of application used for recovering or replacing an existing roof covering shall comply with the requirements of this chapter.

  Exceptions:

  1. Reroofing shall not be required to meet the minimum design slope requirement of one-quarter unit vertical in 12 units horizontal (2-percent slope) in Section R905 for roofs that provide positive roof drainage.
  2. For roofs that provide positive drainage, recovering or replacing an existing roof covering shall not require the secondary (emergency overflow) drains or scuppers of Section R903.4.1 to be added to an existing roof.

  R908.2 Structural and construction loads. The structural roof components shall be capable of supporting the roof covering system and the material and equipment loads that will be encountered during installation of the roof covering system.

  R908.3 Roof replacement. Roof replacement shall include the removal of existing layers of roof coverings down to the roof deck.

  Exceptions:

  1. Where the existing roof assembly includes an ice barrier membrane that is adhered to the roof deck and the existing sheathing is not water soaked or deteriorated to the point that it is not adequate as a base for additional roofing, the existing ice barrier membrane shall be permitted to remain in place and covered with an additional layer of ice barrier membrane in accordance with Section R905 where permitted by the roof covering manufacturer and new ice barrier underlayment manufacturer.
  2. Where the existing roof includes a self-adhered underlayment and the existing sheathing is not water soaked or deteriorated to the point that it is not adequate as a base for additional roofing, the existing self-adhered underlayment shall be

  2025 CALIFORNIA RESIDENTIAL CODE 9-19

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  �

  ROOF ASSEMBLIES

  permitted to remain in place and covered with an underlayment complying with Table R905.1.1(1), Table R905.1.1(2) and Table R905.1.1(3). 3.

• CBC § 203.1.2 Medium relevance — show source text

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

  APPENDIX A4 — RESIDENTIAL VOLUNTARY MEASURES

  A4.203.1.2 Prerequisite options. In addition, a minimum of TWO of the efficiency measures specified in Sections A4.203.1.2.1 through A4.203.1.2.7 must be met.

  A4.203.1.2.1 Roof deck insulation, or ducts in conditioned space. Meet one of the three options for the location of ducts and air handlers as well as insulation R -values and installation of a radiant barrier as specified in Title 24, Part 6, Section 150.1(c)9A or B:

  1. Below roof deck insulation with a minimum R -value of 19; or,

  2. Continuous above deck insulation with a minimum R-8 and with an air space present between the roofing and the roof deck; or,

  3. All ducts and air handlers in conditioned space as specified in the Title 24, Part 6, Reference Appendix RA3.1.

  A4.203.1.2.2 High performance walls. Meet the climate zone dependent U -factor or insulation R -value for either 2x6 or 2x4 framing as specified in Title 24, Part 6, Section 150.1(c)1B: maximum U -factor of 0.048.

  A4.203.1.2.3 Compact hot water distribution system. Meet the requirements for installation of Compact Hot Water Distribution Systems specified in the Title 24, Part 6, Reference Appendix RA3.6.5.

  A4.203.1.2.4 Drain water heat recovery. Meet the requirements for installation of Drain Water Heat Recovery specified in Title 24, Part 6, Reference Appendix RA4.4.21.

  A4.203.1.2.5 High performance vertical fenestration. Meet the climate zone dependent U -factor and Solar Heat Gain Coefficient (SHGC) as rated in accordance with Title 24, Part 6, Section 110.6, and shall have a maximum U -factor of 0.21 in Climate Zones 1 − 16, maximum SHGC of 0.23 in Climate Zones 2, 4, and 6 − 14, and maximum SHGC of 0.20 in Climate Zone 15.

  Exception to A4.203.1.2.5: Fenestration in Climate Zones 1, 3, 5, and 16 is not required to comply with the maximum SHGC requirements.

  A4.203.1.2.6 Heat pump water heater demand management. For buildings with heat pump water heating, meet the requirements for installation of controls specified by Title 24, Part 6, Reference Appendix JA13.3.3.

  A4.203.1.2.7 Battery storage system controls. For buildings with battery storage systems, meet the requirements for installation of controls specified by Title 24, Part 6, Reference Appendix JA12 for either the Time-of-Use Control or Advanced Demand Flexibility Control option.

• CFC § 2025 Medium relevance — show source text

  In addition, the special fire protection system requirements based on use and occupancy found in CBC Chapter 4 are duplicated in CFC Chapter 9 as a user convenience.

  Chapter 10 Means of Egress.

  The criteria in Chapter 10 regulating the design of the means of egress system are established as the primary method for protection of occupants by allowing timely relocation or evacuation. Both prescriptive and performance language is utilized for determination of a safe exiting system. It addresses all portions of the means of egress system (i.e., exit access, exits and exit discharge) and includes design requirements as well as provisions regulating individual components. The requirements detail the size, arrangement, number and protection of means of egress components. The means of egress protection requirements work in coordination with other sections of the code, such as protection of vertical openings (see Chapter 7), interior finish (see Chapter 8), fire suppression and detection systems (see Chapter 9) and numerous others, all having an impact on life safety. Chapter 10 of the CBC is duplicated in Chapter 10 of the CFC; however, the CFC contains one additional section on the maintenance of the means of egress system in existing buildings.

  Chapter 11 Reserved.

  Chapter 11A Housing Accessibility. Chapter 11B Accessibility to Public Buildings, Public Accommodations, Commercial Buildings and Public Housing.

  Verify compliance with accessibility provisions. In order to be considered as accessible, buildings and their individual elements must comply with the applicable scoping and technical provisions of Chapter 11A and/or Chapter 11B.

  Chapter 12 Interior Environment.

  Chapter 12 provides minimum standards for the interior environment of a building. The standards address the minimum sizes of spaces, as well as minimums for temperature, light and ventilation. Concerns for sound transmission and acoustics are addressed. Finally, the chapter provides minimum standards for toilet and bathroom construction.

  Chapter 13 Energy Efficiency.

  Chapter 13 is not adopted in California. Refer to California Energy Code, Title 24, Part 6.

  Chapter 14 Exterior Walls.

  Chapter 14 addresses requirements for exterior walls of buildings. Minimum standards for wall covering materials, installation of wall coverings and the ability of the wall to provide weather protection are provided.

  Chapter 15 Roof Assemblies and Rooftop Structures.

  Chapter 15 provides standards for both roof assemblies and structures that sit on top of the roofs of buildings. The criteria address roof construction and covering, including the weather-protective barrier at the roof and, in most circumstances, a fire-resistant barrier.

  xiv 2025 CALIFORNIA BUILDING CODE

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

  Chapter 16 Structural Design.

  Chapter 16 prescribes minimum structural loading requirements for use in the design and construction of buildings and structural components. The chapter references and relies on many nationally recognized design standards, including the American Society of Civil Engineers’ Minimum Design Loads for Buildings and Other Structures (ASCE 7).

  Chapter 16A Structural Design.