CPC · California Plumbing Code
How must roof drains, strainers and flashings be installed?
For homeowners: roof drains must be made from approved materials, covered with domed strainers (unless the deck exception applies), and the penetration must be made watertight with flashing that meets the code’s minimum lead or copper weights per **§ 1102.1–1102.3**.
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
Roof drains must be made of an approved material and comply with ASME A112.3.1 or A112.6.4 as specified in § 1102.1. Every roof drain must have a domed strainer (with a limited exception for some decks) per § 1102.2. Where drains pass through the roof into the building the connection must be made watertight by proper flashing material, with minimum material weights specified for lead and copper in § 1102.3.
The most important rule: make the drain from an approved listed material, cover it with the required domed strainer (unless the stated exception applies), and make the roof-to-drain connection watertight with flashing meeting the minimum weight requirements.
Requirements in detail
Materials and listing
- Permitted drain body materials include aluminum, cast iron, copper alloy (≤ 15% zinc), leaded nickel bronze, stainless steel, ABS, PVC, polypropylene, polyethylene, or nylon. These drains must comply with ASME A112.3.1 or ASME A112.6.4 per § 1102.1.
Strainers
- Domed strainers are required on all roof drains (§ 1102.2).
- Exception: flat surface type strainers are allowed when used on sun decks, parking decks, and similar areas that are normally serviced and maintained; these flat strainers must be level with the deck (§ 1102.2).
Flashings and watertight connection
- The roof penetration at drains that pass through the roof and into the interior must be made watertight by proper flashing material (§ 1102.3).
- Minimum flashing material weights:
- Lead flashing: not less than 4 pounds per square foot (19 kg/m²) — § 1102.3.1.
- Copper flashing: not less than 12 ounces per square foot (3.7 kg/m²) — § 1102.3.2.
Decision table — quick reference
| Item | Required value / condition | Code Reference |
|---|---|---|
| Permitted drain materials | Aluminum, cast-iron, copper alloy (≤15% Zn), leaded nickel bronze, stainless steel, ABS, PVC, polypropylene, polyethylene, nylon; ASME A112.3.1 or A112.6.4 required | § 1102.1 |
| Strainer type | Domed strainer required | § 1102.2 |
| Strainer exception | Flat surface strainer allowed on sun decks, parking decks, and similar areas; must be level with the deck | § 1102.2 |
| Flashing watertightness | Connection must be watertight by proper flashing material | § 1102.3 |
| Lead flashing minimum weight | 4 lb/ft² (≈19 kg/m²) | § 1102.3.1 |
| Copper flashing minimum weight | 12 oz/ft² (≈3.7 kg/m²) | § 1102.3.2 |
Exceptions & special cases
- Flat strainers: permitted only for sun decks, parking decks, and similar areas that are normally serviced and maintained, and they must be level with the deck (the only exception listed in § 1102.2).
- The code text in the retrieved sections does not add other exceptions for materials, strainers, or flashings; any additional allowance would need to come from other code sections, local amendments, or an approved alternative method. If you need guidance beyond these subsections, the applicable authority having jurisdiction must be consulted.
Common mistakes
- Installing a non‑listed drain material or a drain that does not comply with ASME A112.3.1 / A112.6.4 — check manufacturer documentation and listing before installation (§ 1102.1).
- Using a flat strainer on a roof area that is not a sun deck, parking deck, or similarly maintained area (violates § 1102.2).
- Failing to make the roof‑to‑drain connection watertight or using flashing lighter than the minimum specified for lead or copper (violates § 1102.3, § 1102.3.1, § 1102.3.2).
- Setting a flat strainer proud of the deck surface when the exception requires it to be level with the deck (also § 1102.2).
Worked example
Scenario: You are specifying a roof drain for a commercial flat roof restroom addition (not a sun deck or parking deck).
- Choose drain body: select a PVC roof drain listed to ASME A112.3.1 (acceptable per § 1102.1). Verify the manufacturer’s listing and product data.
- Strainer: install a domed strainer over that drain (required by § 1102.2). Do not use a flat strainer because this is not a sun deck/parking deck.
- Flashing: the drain passes through the roof into the interior, so the roof‑to‑drain connection must be watertight using proper flashing material (§ 1102.3). If specifying copper flashing, provide copper at not less than 12 oz/ft² per § 1102.3.2. If lead flashing were chosen (rare in modern new work), specify not less than 4 lb/ft² per § 1102.3.1.
Result: PVC drain (ASME listed) + domed strainer + copper flashing at 12 oz/ft² = conforms to the cited CPC subsections. Confirm manufacturer instructions and coordinate with roofing system to ensure watertight integration.
Related provisions
- § 1103.1 — sizing of vertical conductors and leaders (roof drainage sizing uses projected roof area).
- § 1103.2 — sizing of horizontal storm drains and sewers.
- § 1105.1 — controlled‑flow roof drainage (limits on stored water depth at drains).
- § 1105.2 — setback roofs (how setback drains may connect to controlled‑flow systems).
- § 1101.15 — traps on storm drains and leaders (where traps are required or not).
Code references
Grounded in the retrieved California Plumbing Code — click a citation to read the verbatim passage:
CPC § 1101.16 High relevance — show source text
1101.16 Leaders, Conductors, and Connections. Leaders or conductors shall not be used as soil, waste, or vent pipes nor shall soil, waste, or vent pipes be used as leaders or conductors.
1101.16.1 Protection of Leaders. Leaders installed along alleyways, driveways, or other locations where exposed to damage shall be protected by metal guards, recessed into the wall, or constructed from the ferrous pipe. 1101.16.2 Combining Storm with Sanitary Drainage. The sanitary and storm drainage system of a building shall be entirely separate, except where a combined sewer is used, in which case the building storm drain shall be connected in the same horizontal plane through a single wye fitting to the combined building sewer not less than 10 feet (3048 mm) downstream from a soil stack.
1102.0 Roof Drains.
1102.1 Applications. Roof drains shall be constructed of aluminum, cast-iron, copper alloy of not more than 15 percent zinc, leaded nickel bronze, stainless steel, ABS, PVC, polypropylene, polyethylene, or nylon and shall comply with ASME A112.3.1 or ASME A112.6.4.
1102.2 Dome Strainers Required. Roof drains shall have domed strainers.
Exception: Roof drain strainers for use on sun decks, parking decks, and similar areas that are normally serviced and maintained, shall be permitted to be of the flat surface type. Such roof drain strainers shall be level with the deck.
1102.3 Roof Drain Flashings. The connection between the roof and roof drains that pass through the roof and into the interior of the building shall be made watertight by the use of proper flashing material. 1102.3.1 Lead Flashing. Where lead flashing material is used, it shall be not less than 4 pounds per square foot (lb/ft [2] ) (19 kg/m [2] ). 1102.3.2 Copper Flashing. Where copper flashing material is used, it shall be not less than 12 ounces per square foot (oz/ft [2] ) (3.7 kg/m [2] ).
1103.0 Size of Leaders, Conductors, and Storm Drains.
1103.1 Vertical Conductors and Leaders. Vertical conductors and leaders shall be sized by the maximum projected roof area and Table 1103.1.
1103.2 Size of Horizontal Storm Drains and Sewers. The size of building storm drains, or building storm sewers or their horizontal branches shall be based on the maximum projected roof or paved area to be handled and Table 1103.2.
1103.3 Size of Roof Gutters. The size of semi-circular gutters shall be based on the maximum projected roof area and Table 1103.3.
1103.4 Side Walls Draining onto a Roof. Where vertical walls project above a roof to permit storm water to drain into the roof area below, the adjacent roof area shall be permitted to be computed from Table 1103.1 as follows:
(1) For one wall – add 50 percent of the wall area to the roof area figures.
(2) For two adjacent walls of equal height – add 35 percent of the total wall areas.
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CPC § 1103.1 High relevance — show source text
(3) Not less than two drains shall be installed in roof areas of 10 000 square feet (929 m [2] ) or less, and not less than one additional drain shall be installed for each 10 000 square feet (929 m [2] ) of roof area exceeding 10 000 square feet (929 m [2] ). (4) Each roof drain shall have a precalibrated, fixed (nonadjustable), and proportional weir (notched) in a standing water collar inside the strainer. No mechanical devices or valves shall be permitted. (5) Pipe sizing shall be based on the pre-calibrated rate of flow (gpm) (L/s) of the pre-calibrated weir for the maximum allowable water depth, and Table 1103.1 and Table 1103.2.
(6) The height of stones or other granular material above the waterproofed surface shall not be considered in water depth measurement, and the roof surface in the vicinity of the drain shall not be recessed to create a reservoir.
(7) Roof design, where controlled-flow roof drainage is used, shall be such that the design roof live load is not less than 30 lb/ft [2] (146 kg/m [2] ) to provide a safety factor exceeding the 15 lb/ft [2] (73 kg/m [2] ) represented by the depth of water stored on the roof in accordance with Table 1105.1(1). (8) Scuppers shall be provided in parapet walls. The distance of scupper bottoms above the roof level at the drains shall not exceed the maximum distances specified in Table 1105.1(2).
(9) Scupper openings shall be not less than 4 inches (102 mm) high and have a width equal to the circumference of
208 2025 CALIFORNIA PLUMBING CODE
), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
STORM DRAINAGE
the roof drain required for the area served, sized in accordance with Table 1103.1.
(10)Flashings shall extend above the top of the scuppers.
(11)At a wall or parapet, 45 degree (0.79 rad) cants shall be installed.
(12)Separate storm and sanitary drainage systems shall be provided within the building.
(13)Calculations for the roof drainage system shall be submitted along with the plans to the Authority Having Jurisdiction for approval.
TABLE 1105.1(1) CONTROLLED-FLOW MAXIMUM ROOF WATER DEPTH
ROOF RISE*
(inches)MAXIMUM WATER DEPTH AT
DRAIN
(inches)
Flat3
24
45
66 For SI units: 1 inch = 25.4 mm
- Vertical measurement from the roof surface at the drain to the highest point of the roof surface served by the drain, ignoring a local depression immediately adjacent to the drain.
TABLE 1105.1(2) DISTANCE OF SCUPPER BOTTOMS ABOVE ROOF
CPC § 2.1 High relevance — show source text
R903.2.1 Locations. Flashings shall be installed at wall and roof intersections, wherever there is a change in roof slope or direction and around roof openings. A flashing shall be installed to divert the water away from where the eave of a sloped roof intersects a vertical sidewall. Where flashing is of metal, the metal shall be corrosion resistant with a thickness of not less than 0.019 inch (0.5 mm) (No. 26 galvanized sheet).
R903.2.2 Crickets and saddles. A cricket or saddle shall be installed on the ridge side of any chimney or penetration more than 30 inches (762 mm) wide as measured perpendicular to the slope. Cricket or saddle coverings shall be sheet metal or of the same material as the roof covering.
Exception: Unit skylights installed in accordance with Section R324.6 and flashed in accordance with the manufacturer’s instructions shall be permitted to be installed without a cricket or saddle.
R903.3 Coping. Parapet walls shall be properly coped with noncombustible, weatherproof materials of a width not less than the thickness of the parapet wall.
R903.4 Roof drainage. Unless roofs are sloped to drain over roof edges, roof drains shall be installed at each low point of the roof.
R903.4.1 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. Overflow drains having the same size as the roof drains shall be installed with the inlet flow line located 2 inches (51 mm) above the low point of the roof, or overflow scuppers having three times the size of the roof drains and having a minimum opening height of 4 inches (102 mm) shall be installed in the adjacent parapet walls with the inlet flow located 2 inches (51 mm) above the low point of the roof served. The installation and sizing of overflow drains, leaders and conductors shall comply with the California Plumbing Code .
SECTION R904—MATERIALS
R904.1 Scope. The requirements set forth in this section shall apply to the application of roof covering materials specified herein. Roof assemblies shall be applied in accordance with this chapter and the manufacturer’s installation instructions. Installation of roof assemblies shall comply with the applicable provisions of Section R905.
R904.2 Compatibility of materials. Roof assemblies shall be of materials that are compatible with each other and with the building or structure to which the materials are applied.
R904.3 Material specifications and physical characteristics. Roof covering materials shall conform to the applicable standards listed in this chapter.
R904.4 Product identification. Roof covering materials shall be delivered in packages bearing the manufacturer’s identifying marks and approved testing agency labels required. Bulk shipments of materials shall be accompanied by the same information issued in the form of a certificate or on a bill of lading by the manufacturer.
SECTION R905—REQUIREMENTS FOR ROOF COVERINGS
R905.1 Roof covering application. Roof coverings shall be applied in accordance with the applicable provisions of this section and the manufacturer’s installation instructions. Unless otherwise specified in this section, roof coverings shall be 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).
CPC § 1101.16 High relevance — show source text
1101.16 Leaders, Conductors, and
Connections . . . . . . . . . . . . . . . . .207
1102.0 Roof Drains . . . . . . . . . . . . . . . . . .207
1102.1 Applications . . . . . . . . . . . . . . . . .207
1102.2 Dome Strainers Required . . . . . . .207
1102.3 Roof Drain Flashings . . . . . . . . . .207
1103.0 Size of Leaders, Conductors,
and Storm Drains . . . . . . . . . . . . .207
1103.1 Vertical Conductors and
Leaders . . . . . . . . . . . . . . . . . . . . .207
1103.2 Size of Horizontal Storm
Drains and Sewers . . . . . . . . . . . .207
1103.3 Size of Roof Gutters . . . . . . . . . . .207
1103.4 Side Walls Draining onto a Roof . . . . . . . . . . . . . . . . . .207
Table 1103.1 Sizing Roof Drains, Leaders, and Vertical Rainwater Piping . . .208
1104.0 Values for Continuous Flow . . . . .208
1104.1 General . . . . . . . . . . . . . . . . . . . . .208
1105.0 Controlled-Flow Roof
Drainage . . . . . . . . . . . . . . . . . . . .208
1105.1 Application . . . . . . . . . . . . . . . . . .208
Table 1105.1(1) Controlled-Flow Maximum Roof Water Depth . . . . . . . . . . . . .209
Table 1105.1(2) Distance of Scupper Bottoms Above Roof . . . . . . . . . . . . . . . . . .209
xxxviii 2025 CALIFORNIA PLUMBING CODE
), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
TABLE OF CONTENTS
1105.2 Setback Roofs . . . . . . . . . . . . . . .209
1106.0 Engineered Storm Drainage System . . . . . . . . . . . . . . . . . . . . .209
1106.1 General . . . . . . . . . . . . . . . . . . . . .209
1106.2 Siphonic Roof Drainage Systems . . . . . . . . . . . . . . . . . . . .209
1106.3 Siphonic Roof Drains . . . . . . . . . .209
1107.0 Testing . . . . . . . . . . . . . . . . . . . . .209
1107.1 Testing Required . . . . . . . . . . . . .209
1107.2 Methods of Testing Storm Drainage Systems . . . . . . . . . . . .209
Table 1103.2 Sizing of Horizontal Rainwater Piping . . . . . . . . . . . . .210
Table 1103.3 Size of Gutters . . . . . . . . . . . . . . .211
CPC § 1103.1. High relevance — show source text
(9) Scupper openings shall be not less than 4 inches (102 mm) high and have a width equal to the circumference of
208 2025 CALIFORNIA PLUMBING CODE
), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
STORM DRAINAGE
the roof drain required for the area served, sized in accordance with Table 1103.1.
(10)Flashings shall extend above the top of the scuppers.
(11)At a wall or parapet, 45 degree (0.79 rad) cants shall be installed.
(12)Separate storm and sanitary drainage systems shall be provided within the building.
(13)Calculations for the roof drainage system shall be submitted along with the plans to the Authority Having Jurisdiction for approval.
TABLE 1105.1(1) CONTROLLED-FLOW MAXIMUM ROOF WATER DEPTH
ROOF RISE*
(inches)MAXIMUM WATER DEPTH AT
DRAIN
(inches)
Flat3
24
45
66 For SI units: 1 inch = 25.4 mm
- Vertical measurement from the roof surface at the drain to the highest point of the roof surface served by the drain, ignoring a local depression immediately adjacent to the drain.
TABLE 1105.1(2) DISTANCE OF SCUPPER BOTTOMS ABOVE ROOF
ROOF RISE*
(inches)ABOVE ROOF LEVEL
AT DRAIN
(inches)
Flat3
24
45
66 For SI units: 1 inch = 25.4 mm
- Vertical measurement from the roof surface at the drain to the highest point of the roof surface served by the drain, ignoring a local depression immediately adjacent to the drain.
1105.2 Setback Roofs. Drains on setback roofs shall be permitted to be connected to the controlled-flow drainage systems provided:
(1) The setback is designed for storing water, or
(2) The square footage of the setback drainage area is converted as outlined in Section 1105.0 to gpm, and the storm-water pipe sizes in the controlled-flow system are based on the sum of the loads.
(3) The branch from each of the roof drains that are not provided with controlled flow shall be sized in accordance
with Table 1103.1.
1106.0 Engineered Storm Drainage System. 1106.1 General. The design and sizing of a storm drainage system shall be permitted to be determined by accepted engineering practices. The system shall be designed by a regis
TABLE 1105.1(1) CONTROLLED-FLOW MAXIMUM ROOF WATER DEPTH
For SI units: 1 inch = 25.4 mm
- Vertical measurement from the roof surface at the drain to the highest point of the roof surface served by the drain, ignoring a local depression immediately adjacent to the drain.
TABLE 1105.1(2) DISTANCE OF SCUPPER BOTTOMS ABOVE ROOF
For SI units: 1 inch = 25.4 mm
CPC § 1101.1 High relevance — show source text
1101.1 Applicability . . . . . . . . . . . . . . . . . .205
1101.2 Where Required . . . . . . . . . . . . . .205
1101.3 Storm Water Drainage to Sanitary Sewer Prohibited . . . . . .205
1101.4 Material Uses . . . . . . . . . . . . . . . .205
Table 1101.4.6 Materials for Subsoil Drainpipe and Fittings . . . . . . . . . . . . . . . . . .205
1101.5 Expansion Joints Required . . . . . .205
1101.6 Subsoil Drains . . . . . . . . . . . . . . .205
1101.7 Building Subdrains . . . . . . . . . . . .206
1101.8 Areaway Drains . . . . . . . . . . . . . .206
1101.9 Window Areaway Drains . . . . . . .206
1101.10 Filling Stations and Motor Vehicle Washing Establishments . . . . . . . . . . . . . . .206
1101.11 Paved Areas . . . . . . . . . . . . . . . . .206
1101.12 Roof Drainage . . . . . . . . . . . . . . .206
1101.13 Cleanouts . . . . . . . . . . . . . . . . . . .207
1101.14 Rainwater Sumps . . . . . . . . . . . . .207
1101.15 Traps on Storm Drains and Leaders . . . . . . . . . . . . . . . . . . . . .207
1101.16 Leaders, Conductors, and
Connections . . . . . . . . . . . . . . . . .207
1102.0 Roof Drains . . . . . . . . . . . . . . . . . .207
1102.1 Applications . . . . . . . . . . . . . . . . .207
1102.2 Dome Strainers Required . . . . . . .207
1102.3 Roof Drain Flashings . . . . . . . . . .207
1103.0 Size of Leaders, Conductors,
and Storm Drains . . . . . . . . . . . . .207
1103.1 Vertical Conductors and
Leaders . . . . . . . . . . . . . . . . . . . . .207
1103.2 Size of Horizontal Storm
Drains and Sewers . . . . . . . . . . . .207
1103.3 Size of Roof Gutters . . . . . . . . . . .207
1103.4 Side Walls Draining onto a Roof . . . . . . . . . . . . . . . . . .207
Table 1103.1 Sizing Roof Drains, Leaders, and Vertical Rainwater Piping . . .208
1104.0 Values for Continuous Flow . . . . .208
1104.1 General . . . . . . . . . . . . . . . . . . . . .208
1105.0 Controlled-Flow Roof
Drainage . . . . . . . . . . . . . . . . . . . .208
CPC § 1.2. High relevance — show source text
R902.3 Building-integrated photovoltaic (BIPV) systems. Building-integrated photovoltaic (BIPV) systems installed as the roof covering shall be tested, listed and labeled for fire classification in accordance with UL 7103 [SFM] Section R902.1 through R902.1.2. Class A, B or C BIPV products shall be installed where the edge of the roof is less than 3 feet (914 mm) from a lot line.
R902.4 Rooftop-mounted photovoltaic (PV) panel systems. Rooftop-mounted photovoltaic (PV) panel systems installed on or above the roof covering shall be tested, listed and identified with a fire classification in accordance with UL 2703. Listed systems shall be installed in accordance with the manufacturer’s installation instructions and their listing. Class A, B or C photovoltaic panel systems
2025 CALIFORNIA RESIDENTIAL CODE 9-3
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ROOF ASSEMBLIES
and modules shall be installed in jurisdictions designated by law as requiring their use or where the edge of the roof is less than 3 feet (914 mm) from a lot line.
SECTION R903—WEATHER PROTECTION
R903.1 General. Roof decks shall be covered with approved roof coverings secured to the building or structure in accordance with the provisions of this chapter. Roof assemblies shall be designed and installed in accordance with this code and the approved manufacturer’s instructions such that the roof assembly shall serve to protect the building or structure.
R903.2 Flashing. Flashings shall be installed in a manner that prevents moisture 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.
R903.2.1 Locations. Flashings shall be installed at wall and roof intersections, wherever there is a change in roof slope or direction and around roof openings. A flashing shall be installed to divert the water away from where the eave of a sloped roof intersects a vertical sidewall. Where flashing is of metal, the metal shall be corrosion resistant with a thickness of not less than 0.019 inch (0.5 mm) (No. 26 galvanized sheet).
R903.2.2 Crickets and saddles. A cricket or saddle shall be installed on the ridge side of any chimney or penetration more than 30 inches (762 mm) wide as measured perpendicular to the slope. Cricket or saddle coverings shall be sheet metal or of the same material as the roof covering.
Exception: Unit skylights installed in accordance with Section R324.6 and flashed in accordance with the manufacturer’s instructions shall be permitted to be installed without a cricket or saddle.
R903.3 Coping. Parapet walls shall be properly coped with noncombustible, weatherproof materials of a width not less than the thickness of the parapet wall.
R903.4 Roof drainage. Unless roofs are sloped to drain over roof edges, roof drains shall be installed at each low point of the roof.
R903.4.1 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.
CPC § 10-3 Medium relevance — show source text
1003 Building Elements and Materials . . . . . . . . . . . . . . . . 10-3
1004 Fire Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3
1005 Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3
1006 Structural. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3
1007 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-4
1008 Mechanical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-4
1009 Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-4
1010 Other Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-5
1011 Change of Occupancy Classification . . . . . . . . . . . . . 10-5
CHAPTER 11 ADDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . .11-3
1101 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-3
1102 Heights and Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-3
1103 Structural. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
1104 Energy Conservation. . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
CHAPTER 12 HISTORIC BUILDINGS . . . . . . . . . . . . . . . . . .12-1
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CHAPTER 13 PERFORMANCE COMPLIANCE METHODS. . 13-3
1301 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-3
1302 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-3
1303 Acceptance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-4
CPC § 1101.13.1 Medium relevance — show source text
1101.13.1 Rain Leaders and Conductors. Rain leaders and conductors connected to a building storm sewer shall have a cleanout installed at the base of the
leader or conductor before it connects to the horizontal
drain.
1101.14 Rainwater Sumps. Rainwater sumps serving “public use” occupancy buildings shall be provided with dual pumps arranged to function alternately in the case of overload or mechanical failure. Pumps rated 600 V or less shall comply with UL 778 and shall be installed in accordance with the manufacturer’s installation instructions.
1101.15 Traps on Storm Drains and Leaders. Leaders and storm drains, where connected to a combined sewer, shall be trapped. Floor and area drains connected to a storm drain shall be trapped.
Exception: Traps shall not be required where roof drains, rain leaders, and other inlets are at locations permitted under Section 906.0, Vent Termination.
1101.15.1 Where Not Required. No trap shall be required for leaders or conductors that are connected to a sewer carrying storm water exclusively. 1101.15.2 Trap Size. Traps, where installed for individual conductors, shall be the same size as the horizontal drain to which they are connected.
1101.15.3 Method of Installation of Combined Sewer. Individual storm-water traps shall be installed on the stormwater drain branch serving each storm-water inlet, or a single trap shall be installed in the main storm drain just before its connection with the combined building sewer. Such traps shall be provided with an accessible cleanout on the outlet side of the trap.
1101.16 Leaders, Conductors, and Connections. Leaders or conductors shall not be used as soil, waste, or vent pipes nor shall soil, waste, or vent pipes be used as leaders or conductors.
1101.16.1 Protection of Leaders. Leaders installed along alleyways, driveways, or other locations where exposed to damage shall be protected by metal guards, recessed into the wall, or constructed from the ferrous pipe. 1101.16.2 Combining Storm with Sanitary Drainage. The sanitary and storm drainage system of a building shall be entirely separate, except where a combined sewer is used, in which case the building storm drain shall be connected in the same horizontal plane through a single wye fitting to the combined building sewer not less than 10 feet (3048 mm) downstream from a soil stack.
1102.0 Roof Drains.
1102.1 Applications. Roof drains shall be constructed of aluminum, cast-iron, copper alloy of not more than 15 percent zinc, leaded nickel bronze, stainless steel, ABS, PVC, polypropylene, polyethylene, or nylon and shall comply with ASME A112.3.1 or ASME A112.6.4.
1102.2 Dome Strainers Required. Roof drains shall have domed strainers.
Exception: Roof drain strainers for use on sun decks, parking decks, and similar areas that are normally serviced and maintained, shall be permitted to be of the flat surface type. Such roof drain strainers shall be level with the deck.
CPC § 11-3 Medium relevance — show source text
1101 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-3
1102 Heights and Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-3
1103 Structural. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
1104 Energy Conservation. . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4
CHAPTER 12 HISTORIC BUILDINGS . . . . . . . . . . . . . . . . . .12-1
xviii 2025 CALIFORNIA EXISTING BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
CHAPTER 13 PERFORMANCE COMPLIANCE METHODS. . 13-3
1301 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-3
1302 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-3
1303 Acceptance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-4
1304 Investigation and Evaluation . . . . . . . . . . . . . . . . . . . 13-4
1305 Scoring and Evaluation . . . . . . . . . . . . . . . . . . . . . . . . 13-4
1306 Building Score . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-14
1307 Evaluation of Building Safety. . . . . . . . . . . . . . . . . . 13-16
CHAPTER 14 RELOCATED OR MOVED BUILDINGS . . . . . . 14-3
1401 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-3
1402 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-3
CHAPTER 15 CONSTRUCTION SAFEGUARDS . . . . . . . . . . 15-3
1501 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-3
1502 Owner’s Responsibility for Fire Protection . . . . . . . 15-3
1503 Sanitary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-4
CPC § 907.5.2.3.1 Medium relevance — show source text
Employee Accessibility for work areas 907.5.2.3.1, Chapter 11B Deputies to building official 103.3 Liability 104.8 Qualifications A101 Termination of employment A101.4 Toilet facilities Chapter 11B Encroachments Into the Public Right-of-Way Chapter 32 End-Jointed Lumber 2303.1.1.2
Relocated structures 101.4.7, D103.3 Rodentproofing Appendix F
INDEX-6 2025 CALIFORNIA BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
Energy Efficiency Chapter 13, 101.4.6, 110.3.9 Enforcing Agency 202 Housing and Community Development 1.8 Engineer (see Definition for Registered Design Professional) Entrances 905.3.3, 1030.4, Chapter 11B Equipment Countertop Equipment 202 Essential Equipment 202 Fixed Equipment 202 Interim Equipment 202 Mobile Equipment 202 Movable Equipment 202 Other Equipment 202 Temporary Equipment 202 Equipment Platform 505.3 Area limitation 505.2.1, 505.2.1.1,
505.3.1 Automatic sprinkler system 505.3.2 Equivalent Opening Factor Figure 705.8 Escalators 3004 Floor opening protection 712.1.3 Means of egress 1003.7 Essential Facilities (see Risk Category) Table 1604.5 Excavation, Grading and Fill 1804, 3304 Existing Building 101.4.7, 102.6, 705.3, 912.2.2, 915.1, 11B- 202 Additions D103.1
Alteration D103.1 Change of occupancy D103.2 Flood-resistant 104.3.1, Appendix G Historic 101.4.7
Relocated structures D103.3
Repairs 101.4.7, 116.5 Rodentproofing Appendix F Exit (see Means of Egress) 1022, 1023, 1024, 1025, 1026, 1027 Atrium 404.10, 1023.2 Boiler room 1006.2.1.1 Configuration 1007 Construction 713.2, 1019, 1023.2 Doorways 1007 Dwellings 1006.2.2.6, 1006.3.4.1 Electrical rooms 1006.2.2.4
Enclosure 707.3.2, 1023.2 Fire resistance 707.3, 1019, 1023.2
Furnace rooms 1006.2.2.1
Group H-5 415.11.6.6 High rise 403.5, 403.6, 1025 Horizontal 707.3.5, 1026 Incinerator rooms 1006.2.2.1
CPC § 505.2 Medium relevance — show source text
3, 505.2, 603 Level 3 Chapter 9, 106.2.3, 604, 1011.4 Alternative Materials, Design and Methods of Construction 104.2.3 Ambulatory Care Facility 202, 302.2.1, 406.1.2, 408.3, 501.3, 503.15, 503.17, 804.4,
902.3
Appeals 104.8, 112, 116.6 Approved 202 Approved Agency A304.2.6, 104.2.3.6.1, 202 Archaic Materials and Assemblies
Resource A
Architect (see Registered Design Professional) Area (see Building) Automatic Sprinkler System 110.2, 501.2, 504.5, 802.2.1, 802.6, 803.1.1, 803.2, 804.5.1.1, Table 804.5.1.1(1), 804.5.1.2.1, 804.5.1.2.2, 804.7.1, 804.8, 904.1, 1011.2.1, 1011.6.1, 1011.6.1.1, 1011.7.3, 1011.8.3, 1305.1.1, Table 1305.2.9, 1305.2.10.1, 1305.2.17, 1305.2.17.1, Table 1305.2.17, 1305.2.19, Table 1305.2.19, 1507
Board of Appeals 104.8, 112, Appendix D Building Area 503.5, 503.7, 503.8, 503.9, 503.10, 503.11, 503.16, 503.18, 506.5.2, 506.5.3, 506.6, 603.1, 604.1, 1006.2, 1006.3, 1011.6, 1011.6.1, 1011.6.1.1, 1011.6.2, Table 1011.6, 1102, 1302.1.3, 1305.2.2 Dangerous 104.4, 114.1, 117.1, 202, 302.1 Height 202, 502.1, 804.4.1.1, 1011.6, Table 1011.6, 1011.7.1, 1011.7.3, 1102, 1302.1.3, 1305.2.1, Table 1306.1, A301.2 Historic Chapter 12, 202, 401.1, 501.1, 507, 601.1, 607, 701.1, 1301.1, B101 Relocatable 202, 1401.1 Relocated Chapter 14, 301.4
INDEX
Relocation of 101.2, 101.3, 101.4, 104.3, 301.1 Unsafe 104.4, 115, 116, 117.1, 202
Frequently asked questions
Can I use PVC roof drains?
Yes — PVC is an explicitly listed permitted material for roof drains provided the product complies with ASME A112.3.1 or A112.6.4, per § 1102.1. Verify the listing with the manufacturer.
When is a flat strainer acceptable?
A flat surface strainer is allowed only on sun decks, parking decks, and similar areas that are normally serviced and maintained, and it must be level with the deck (the exception in § 1102.2). Outside those areas, a domed strainer is required.
What if I want to use lead flashing — how thick must it be?
Lead flashing used at roof drains must be not less than 4 pounds per square foot (≈19 kg/m²), per § 1102.3.1.
What minimum copper flashing is required?
Copper flashing must be not less than 12 ounces per square foot (≈3.7 kg/m²), per § 1102.3.2.
Is the roof‑to‑drain connection required to be watertight?
Yes — the connection between the roof and roof drains that pass through the roof into the interior of the building must be made watertight by the use of proper flashing material as required in § 1102.3.
More in California Plumbing Code
- Administration
- Definitions
- General Regulations
- Plumbing Fixtures and Fixture Fittings
- Water Heaters
- Water Supply and Distribution
- Sanitary Drainage (Drain, Waste, and Vent)
- Indirect Wastes
- Vents
- Traps and Interceptors
- Storm Drainage
- Fuel Gas Piping
- Health Care Facilities — Medical Gas and Medical Vacuum Systems
- Alternate Water Sources and Nonpotable Rainwater Catchment Systems
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