Appendix I — INSTALLATION STANDARDS — 2025 California Plumbing Code (Title 24, Part 5)

(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

Adopting Agency	BSC	BSC- CG	SFM	HCD			DSA			OSHPD							BSCC	DPH	AGR	DWR	CEC	CA	SL	SLC
Adopting Agency	BSC	BSC- CG	SFM	1	2	1-AC	AC	SS	SS/CC	1	1R	2	3	4	5	6	6	6	6	6	6	6	6	6
Adopt Entire Chapter										X	X	X	X	X	X	X
Adopt Entire Chapter as amended (amended sections listed below)
Adopt only those sections that are listed below	X			X	X			X
Chapter/Section
IAPMO IS 31-2022	X			X	X			X

This state agency does not adopt sections identified with 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 1.11.0.

448 2025 CALIFORNIA PLUMBING CODE

APPENDIX I

INSTALLATION STANDARDS

CONTENTS

Page

IAPMO IS 26-2019 [e4]

IAPMO IS 31-2022

IAPMO IS 33-2019 [e2]

TCNA Handbook-2022

450 2025 CALIFORNIA PLUMBING CODE

"The information contained in this appendix is not part of this American National Standard (ANS) and has not been processed in accordance with ANSI's requirements for an ANS. As such, this appendix may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements necessary for conformance to the standard."

The following IAPMO Installation Standard is included here for the convenience of the users of the Uniform Plumbing Code. It is not considered as a part of the Uniform Plumbing Code unless formally adopted as such. This Installation Standard is an independent, stand-alone document published by the International Association of Plumbing and Mechanical Officials and is printed herein by the expressed written permission of IAPMO.

TRENCHLESS INSERTION OF

POLYETHYLENE (PE) PIPE FOR SEWER LATERALS

IAPMO IS 26-2019 [e4]

The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.

1 Scope

1.1 General

This standard shall govern the trenchless installation of polyethylene (PE) pipe for use in sanitary and storm sewers. The installed pipe shall comply with the requirements of the Uniform Plumbing Code (UPC [TM] ) published by the International Association of Plumbing and Mechanical Officials (IAPMO) as to grade and connections to existing pipe and shall also comply with this standard. This standard specifies requirements for the installation of the trenchless insertion of polyethylene (PE) pipe for use in sanitary and storm sewers. 1.2 Terminology

In this Standard,

(a) “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy to comply with the Standard;

(b) “should” is used to express a recommendation, but not a requirement;

(d) “can” is used to express a possibility or a capability.

Notes accompanying sections of the Standard do not specify requirements or alternative requirements; their purpose is to separate explanatory or informative material from the text. Notes to tables and figures are considered part of the table or figure and can be written as requirements.

2 Reference Publications

This Standard refers to the following publications, and where such reference is made, it shall be to the current edition of those publications, including all amendments published thereto.

ASTM International

ASTM D3261

Standard Specification for Butt Heat Fusion Polyethylene (PE) Plastic Fittings for Polyethylene (PE) Plastic Pipe and Tubing

ASTM F714

Standard Specification for Polyethylene (PE) Plastic Pipe (DR-PR) Based on Outside Diameter

ASTM F894

Standard Specification for Polyethylene (PE) Large Diameter Profile Wall Sewer and Drain Pipe

ASTM F1055

Standard Specification for Electrofusion Type Polyethylene Fittings for Outside Diameter Controlled Polyethylene and Crosslinked Polyethylene (PEX) Pipe and Tubing

ASTM F2620

Standard Practice for Heat Fusion Joining of Polyethylene Pipe and Fittings

3 Abbreviations

The following abbreviations apply in this Standard:

PE — Polyethylene

HDPE — High Density Polyethylene

4 General

4.1 Product Requirements

Polyethylene (PE) sewer pipe or tubing and fitting joining methods shall be installed in accordance

IS 26

with the manufacturer’s installation instructions and comply with ASTM F714, ASTM F894 the applicable nationally recognized standard.

4.2 HDPE Materials

HDPE Extra High Molecular Weight 3408 SDR 17 Pipe Socket-Type PE Fittings for Outside Diameter Controlled.

Note: The HDPE 3408 SDR 17 pipe used in this process was selected because of its ability to retain its circular shape even when bent on a 1.2 m (4 ft) radius during and after installation. 4.3 Protection of Pipe

Pipe shall be stored in a way to protect it from mechanical damage (slitting, puncturing, etc.). It shall be stored under cover to keep it clean and avoid long term exposure to sunlight. Exposure to sunlight during normal construction periods is acceptable. 4.4 Joining Methods

PE joints shall be made in accordance with the manufacturer’s installation instructions. PE pipe shall be joined to other pipe materials by an approved listed adapter or transition fittings listed for the specific transition intended.

4.4.1 Butt-Fusion Joints [2024 UPC 705.5.1.1]

Butt-fusion joints for PE pipe shall be installed in accordance with ASTM F2620 and shall be made by heating the prepared ends of two pipes, pipe and fitting, or two fittings by holding ends against a heated element. The heated element shall be removed when the required melt or times are obtained, and heated ends shall be placed together with applied force. Do not disturb the joint until cooled to ambient temper ature.

4.4.2 Electro-Fusion Joints [2024 UPC 705.5.1.2]

Electro-fusion joints shall be heated internally by a conductor at the interface of the joint. Fittings shall comply with ASTM F1055 for the performance requirements of polyethylene electro-fusion fittings. The specified electro-fusion cycle used to form the joint requires consideration of the properties of the materials being joined, the design of the fitting being used, and the environmental conditions. Align and restrain fitting to pipe to prevent movement and apply electric current to the fitting. Turn off the current when the required time has elapsed to heat the joint. Do not disturb the joint until cooled to ambient temperature. 4.4.3 Socket-Fusion Joints [2024 UPC 705.5.1.3]

Socket fusion joints shall be installed in accordance with ASTM F2620 and shall be made by simultaneously heating the outside surface of a pipe end and the inside of a fitting socket. Where the required melt is obtained, the pipe and fitting shall be joined by inserting one into the other with applied force. Do not disturb the joint until cooled to ambient temperature.

4.5 Trenchless Installation of Sewers

The trenchless installation of sewers will be as fol lows:

(a) Preliminary Steps (i) Inspect the inside of the sewer line using a camera and recording device to ascertain the line condition.

(ii) Mark the details revealed by the video inspection including:

The ground surface to show the location of the lateral tie of the city wye.
The line location with an arrow in the street pointing back at the lateral.
The property denoting the lateral location.
The locations of the proposed excavations.

(iii) Obtain utility line identification service contact information and all applicable permits. (b) Excavation In addition to the above markings, the local utility companies will mark utilities. Considerations are soil density; clearance from obstacles, utilities, and structures; location of bends, and water service locations. Excavations and shoring shall be in accordance with jurisdictional safety requirements. (c) Set Up Fuse the proper length of polyethylene pipe in accordance with ASTM F2620, or ASTM D3261 and fuse the end to a small length that is attached to the pulling head. A rod pusher cable is pushed through the damaged host pipe and attached to the pulling cable, which is then drawn through the pipe. The clevis end of the cable is attached to the pulling head. The pulling equipment is then set up according to the manufacturer’s instructions.

(d) Pulling Pull the pulling head through. Once the pull is done, complete the connection to the existing piping.

4.6 Cleanouts

4.6.1 Plug Each cleanout fitting for cast-iron pipe shall consist of a cast-iron or brass body and an approved plug. Each cleanout for galvanized wrought-iron, galvanized steel, copper, or brass pipe shall consist of a brass plug as specified in Table 1, or a standard weight brass cap, or an approved ABS or PVC plastic plug, or an approved stainless-steel cleanout or plug. Plugs shall have raised square heads or approved countersunk rectangular slots. 4.6.2 Approved Each cleanout fitting and each cleanout plug, or cap shall be of an approved type.

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4.6.3 Watertight and Gastight

Cleanouts shall be designed to be watertight and gastight.

5 Testing and Inspection Requirements

5.1 Media

The piping of the building sewer shall be tested with water. The Authority Having Jurisdiction shall be permitted to require the removal of cleanouts, etc., to ascertain whether the pressure has reached all parts of the system.

5.2 Water Test

The system shall be tested by plugging the end of the building sewer at its points of connection to the public sewer or private sewage disposal system and completely filling the building sewer with water from the lowest to the highest point thereof.

5.3 Inspections

The completed piping shall be internally inspected by camera unless waived by the Administrative Authority.

TABLE 1

CLEANOUTS (See Section 4.6.1)

NPS	SIZE OF CLEANOUT (inches)	THREADS PER INCH
1.5	1.5	11.5
2	1.5	11.5
2.5	2.5	8
3	2.5	8
4 & larger	3.5	8

Note: For SI units: 1 inch = 25 mm

Uniform Plumbing Code References

The following sections of the 2024 Uniform Plumbing Code apply.

105.2 Required Inspections

105.2.2 Other Inspections

105.3 Testing of Systems

301.2 Minimum Standards

309.0 Workmanship

312.0 Protection of Piping, Materials, and Structures

314.0 Trenching, Excavation, and Backfill

701.3 Drainage Fittings

705.5.1.1 Butt Fusion Joints

705.5.1.2 Electro-Fusion Joints

705.5.1.3 Socket-Fusion Joints

723.0 Building Sewer Test

TABLE 1

CLEANOUTS (See Section 4.6.1)

The following standards from Tables 1701.1 and 1701.2 of the 2024 Uniform Plumbing Code apply.

Table 1701.1 Standards

ASTM D2239 Polyethylene (PE) Plastic Pipe (SIDRPR) Based on Controlled Inside Diameter

ASTM D2683 Socket-Type Polyethylene Fittings for Outside Diameter-Controlled Polyethylene Pipe and Tubing

ASTM D3261 Butt Heat Fusion Polyethylene (PE) Plastic Fittings for Polyethylene (PE) Plastic Pipe and Tubing

ASTM F714 Polyethylene (PE) Plastic Pipe (DRPR) Based on Outside Diameter

ASTM F894 Polyethylene (PE) Large Diameter Profile Wall Sewer and Drain Pipe

ASTM F1055 Electrofusion Type Polyethylene Fittings for Outside Diameter Controlled Polyethylene and Crosslinked Polyethylene (PEX) Pipe and Tubing

ASTM F2620 Heat Fusion Joining of Polyethylene Pipe and Fittings

Table 1701.2 Standards

ASTM D2657 Heat Fusion Joining of Polyolefin Pipe and Fittings

IAPMO PS 25 Metallic Fittings for Joining Polyethylene Pipe for Water Service and Yard Piping

Note: For SI units: 1 inch = 25 mm

454 2025 CALIFORNIA PLUMBING CODE

INSTALLATION STANDARD FOR PEX TUBING SYSTEMS

FOR HOT- AND COLD-WATER DISTRIBUTION

IAPMO IS 31-2022

The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.

1 Scope

1.1 General

1.1.1 This Standard specifies requirements for the installation of SDR 9 CTS crosslinked polyethylene (PEX) tubing and fittings, including cold-expansion, crimp, press, and mechanical compression fittings, intended for hot- and cold-water distribution systems within buildings.

1.1.2 This Standards applies to

(a) SDR 9 CTS PEX tubing complying with ASTM F876 and pressure-rated in accordance with PPI TR-3; and (b) PEX fitting systems complying with (i) ASTM F877, for mechanical compression fittings and metal or plastic insert fittings with stainless steel press sleeves; (ii) ASTM F1807 or ASTM F2159, for metal or plastic insert fittings with copper crimp rings; (iii) ASTM F1960, for cold expansion fittings with PEX reinforced rings; or (iv) ASTM F2080, for cold expansion fittings with metal compression sleeves. 1.2 Terminology

In this Standard,

(a) “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy to comply with the Standard; (b) “should” is used to express a recommendation, but not a requirement; (c) “may” is used to express an option or something permissible within the scope of the Standard; and (d) “can” is used to express a possibility or a capability. Notes accompanying sections of the Standard do not specify requirements or alternative requirements; their purpose is to separate explanatory or informa

tive material from the text. Notes to tables and figures are considered part of the table or figure and can be written as requirements.

1.3 Units of Measurement

SI units are the primary units of record in global commerce. In this Standard, the inch/pound units are shown in parentheses. The values stated in each measurement system are equivalent in application, but each unit system is to be used independently. All references to gallons are to U.S. gallons.

2 Reference Publications

This Standard refers to the following publications, and where such reference is made, it shall be to the current edition of those publications, including all amendments published thereto.

ASTM International

ASTM F876 Standard Specification for Crosslinked Polyethylene (PEX) Tubing

ASTM F877 Standard Specification for Crosslinked Polyethylene (PEX) Hot- and Cold-Water Distribution Systems

ASTM F1807 Standard Specification for Metal Insert Fittings Utilizing a Copper Crimp Ring, or Alternate Stainless Steel Clamps, for SDR9 Crosslinked Polyethylene (PEX) Tubing and SDR9 Polyethylene of Raised Temperature (PE-RT) Tubing

ASTM F1960 Standard Specification for Cold Expansion Fittings with PEX Reinforcing Rings for Use with Cross-linked Polyethylene (PEX) Polyethylene of Raised Temperature (PE-RT) Tubing

IS 31

ASTM F2080 Standard Specification for ColdExpansion Fittings with Metal Compression-Sleeves for CrossLinked Polyethylene (PEX) Pipe and SDR9 Polyethylene of Raised Temperature (PE-RT) Pipe

ASTM F2159 Standard Specification for Plastic Insert Fittings Utilizing a Copper Crimp Ring, or Alternate Stainless Steel Clamps for SDR9 Cross-linked Polyethylene (PEX) Tubing and SDR9 Polyethylene of Raised Temperature (PE-RT) Tubing

ASTM F2657 Standard Test Method for Out door Weathering Exposure of Crosslinked Polyethylene (PEX) Tubing

AWWA (American Water Works Association)

AWWA C904 Cross-Linked Polyethylene (PEX) Pressure Tubing, ½ In. (13 mm) Through 3 In. (76 mm), for Water Service

IAPMO (International Association of Plumb- ing and Mechanical Officials)

IAPMO/ANSI

UPC-1 Uniform Plumbing Code

PPI (Plastics Pipe Institute)

PPI TR-3 Policies and Procedures for

Developing Hydrostatic Design Basis (HDB), Hydrostatic Design Stresses (HDS), Pressure Design Basis (PDB), Strength Design Basis (SDB), Minimum Required Strength (MRS) Ratings, and Categorized Required Strength (CRS) for Thermoplastic Piping Materials or Pipe

3 Abbreviations

The following abbreviations apply in this Standard:

CTS — copper tube size

HDPE — high density polyethylene

IC — insulation contact

NTS — nominal tubing size

PEX — crosslinked polyethylene

SDR — standard dimension ratio

UV — ultraviolet light

4 General

4.1 Tubing

4.1.1 PEX tubing can be

(a) pigmented throughout (i.e., with color); (b) non-pigmented (e.g., translucent or natural); or (c) coated with a pigmented layer. 4.1.2 PEX tubing is typically available in NTS-1/4 to NTS-3.

4.1.3 Before installation, the installer shall review the tubing markings and verify that

(a) the standard designation(s) of the fittings to which the tube can be joined to is included in the markings; (b) it bears a certification mark from an accredited certification organization; and (c) pressure and temperature ratings meet or exceed that of the intended end-use. 4.2 Fittings 4.2.1 Cold-Expansion Fittings

Cold-expansion fittings typically are made of brass, stainless steel, or sulfone; consist of an insert and a PEX reinforcing ring; and are available in NTS-3/8 to NTS-3.

4.2.2 Crimp or Press Insert Fittings

Crimp or press insert fittings typically

(a) are made of brass, stainless steel, or sulfone; (b) consist of an insert and a copper crimp ring or a stainless steel press ring (c) are available in NTS-3/8 to NTS-2 4.2.3 Compression Fittings

Compression (i.e., transition) fittings typically

(a) are made of brass; and (b) consist of (i) a nut, a compression ring, and an insert; or (ii) an O-ring brass insert with a compression sleeve. (c) are available in NTS-1/4 to NTS-3. 4.3 Installation

Only fittings systems marked on the tubing shall be used for installation with that particular tubing.

4.4 Tools

Tools and tool accessories (e.g., tool heads) used for the installation of PEX tubing systems shall be in accordance with the manufacturer’s specifications and written instructions.

4.5 Tubing Protection

4.5.1 Abrasion

PEX tubing passing through drilled or notched metal studs or metal joists, or hollow-shell masonry walls shall be protected from abrasion by elastomeric or plastic sleeves or grommets.

4.5.2 Puncture

Steel-plate protection shall be installed in accordance with the local plumbing code.

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5 Handling 5.1 Receiving

When receiving PEX tubing shipments, the receiver shall inspect and inventory each shipment, ensuring that there has been no loss or damage. In addition:

(a) At the time of unloading, the markings of all tubing, fittings, and accessories shall be verified to ensure that all items have been manufactured in accordance with the applicable product Standard and appropriately certified. (b) An overall examination of the shipment shall be made. If the shipment is intact, ordinary inspection while unloading shall be sufficient to ensure that the items have arrived in good condition. (c) If the load has shifted, has broken packaging, or shows evidence of rough treatment, each item shall be carefully inspected for damage. (d) The total quantities of each shipment (e.g., tubing, gaskets, fittings, and accessories) shall be checked against shipping records. (e) Any damaged or missing items shall be noted on the delivery slip. The carrier shall be notified immediately, and a claim made in accordance with its instructions. (f) No damaged material shall be disposed of. The carrier shall recommend the procedure to follow. (g) Shortages and damaged materials are normally not reshipped without request. If replacement material is needed, it shall be reordered from the manufacturer, the distributor, or a manufacturer’s representative. 5.2 Storage and UV Exposure

5.2.1 PEX tubing and fittings shall be stored indoors and in its original packaging until the time of installation. Appropriate precautions to protect the tubing from damage, impact, and punctures shall be taken.

5.2.2 Accumulative exposure time to UV radiation during storage and installation shall not exceed the UV exposure limits recommended by the manufacturer or specified in ASTM F876. Note: ASTM F876 has four categories for UV-resis- tance, ranging from untested to 6 months of contin- uous exposure, as listed in the material designation code.

5.3 Exposure to Heat

5.3.1 PEX tubing and fittings shall not be exposed to open flames.

5.3.2 PEX tubing shall not be exposed to temperatures exceeding 93 ºC (200ºF). 5.4 Exposure to Chemicals

5.4.1 Chemical compatibility (e.g., with common construction materials) shall be verified with the manufacturer prior to direct contact.

5.4.2 In general, petroleum- or solvent-based chemicals (e.g., paints, greases, pesticides, or sealants) shall not be allowed to come in direct contact with PEX tubing or fittings.

6 Thermal Expansion and Contraction

6.1 Horizontal Tubing Runs

Thermal expansion and contraction forces on suspended horizontal runs of PEX tubing that can experience a 22 ºC (40ºF) or greater change in temperature (operating temperature compared to ambient temperature) shall be controlled by a means of mitigating temperature-induced stresses to other parts of the water distribution system. Means for controlling thermal expansion and contraction include

(a) loops; (b) offsets; (c) arms with rigid anchor points; and (d) supporting the tubing with continuous runs of CTS support channels with (i) rigid anchor points installed every 20 m (65 ft); and (ii) proper strapping (e.g., 27 kg (60 lb) straps or equivalent) spaced 1 m (3 ft) and rated for the maximum temperature and UV exposure of the PEX tubing application. 6.2 Vertical Tubing Runs

Thermal expansion and contraction forces on vertical runs of PEX tubing that pass through more than one floor and can experience a 22 ºC (40ºF) or greater change in temperature (operating temperature compared to ambient temperature) shall be controlled by installing

(a) a riser clamp at the top of every other floor; and (b) mid-story guides to maintain the alignment of the vertical tubing. Note: Installing riser clamps isolates expansion and contraction to two-floor intervals allowing the PEX tubing to naturally compensate for the expan- sion and contraction.

6.3 Clearance

Adequate clearance shall be provided between PEX tubing and the building structure (e.g., using bored holes and sleeves) to allow for free longitudinal movement of the tubing.

6.4 Expansion Arms and Expansion Loops

6.4.1 Expansion Arms (See Figure 1)

6.4.1.1 Expansion arms shall be installed as illustrated in Figure 1.

6.4.1.2 The minimum length of expansion arms shall be calculated using the following equation:

LB = C × √ (D × Δ L)

where

LB = length of flexible arm

C = material constant (12 for PEX)

D = nominal outside diameter of tubing

Δ L = thermal expansion length

IS 31

6.4.2 Expansion Loops (See Figure 2) 6.4.2.1 Expansion loops shall be installed at the mid-point between anchors, as illustrated in Figure 2. 6.4.2.2 The minimum length of expansion loops shall be calculated using the equation in Section 6.4.1.2; however, the distance LB shall be divided into three sections, as illustrated in Figure 2.

where

L1 = LB ÷ 5; and L2 = L1 × 2.

7 Hangers and Supports 7.1 Vertical Tubing

Vertical PEX tubing shall

(a) be supported at each floor or as specified by the water-distribution system designer to allow for expansion and contraction; and (b) have mid-story guides. 7.2 Horizontal Tubing

Unless otherwise authorized by the authority having jurisdiction, suspended horizontal runs of PEX tubing

(a) NTS-1 and smaller shall be supported every 0.8 m (32 in), unless continuously supported by metallic CTS or V channels that (i) are supported at intervals not exceeding 1.8 m (6 ft); (ii) have a maximum cantilever, measured from the support to the end of the CTS support channel, of 0.5 m (1.5 ft); and (b) NTS-1-1/4 and larger shall be supported every 1.2 m (4 ft), unless continuously supported by metallic CTS or V channels that (i) are supported at intervals not exceeding 2.4 m (8 ft); and (ii) have a maximum cantilever, measured from the support to the end of the CTS support channel, of 0.5 m (1.5 ft). 7.3 Anchors

Anchors shall be

(a) used to restrict PEX tubing movement; (b) made of materials that provide rigidity to the support system and utilize pipe clamps designed for plastic tubing capable of restraining the tubing; and (c) installed in accordance with Figures 1 or 2, as applicable (i.e., anchor distances and size of arms and offsets). Note: Anchors are typically installed every 20 m (65 ft). See Section 6.

8 Joints and Connections

8.1 Assembly Procedure

The procedure for making joints shall be as specified by the manufacturer.

8.2 Concealed Joints

PEX tubing systems manufactured in accordance with the applicable standards referenced in Section 2 are deemed manufactured joints and may be installed in concealed spaces without the need for access panels.

9 Clearances

9.1 Gas Vents

Except for double-wall B-vents, which require a 25 mm (1 in) clearance, the clearance between gas appliance vents and PEX tubing shall be at least 150 mm (6 in). 9.2 Recessed Light Fixtures

Except when the PEX tubing is protected with fiberglass or closed-cell insulation or the recessed light is IC-rated, the clearance between recessed light fixtures and PEX tubing shall be at least 300 mm (12 in). 9.3 Fluorescent Lighting

When in direct view of the light source, the clearance between fluorescent lighting and PEX tubing shall be at least 1.5 m (5 ft). If the minimum clearance cannot be achieved, the PEX tubing shall be protected with a UV-blocking sleeve.

10 Other Considerations

10.1 Hot-Work Joints ¶

Hot-work joints (e.g., soldering, brazing, welding, and fusion-welding) shall be

(a) made at least 500 mm (18 in) from PEX tubing in the same water line; and (b) performed prior to completing the PEX joints.

10.2 Bending Radius ¶

10.2.1 The free (unsupported) bending radius for PEX tubing, measured at the outside of the bend, shall be not less than six times the actual outside diameter of the tubing, unless otherwise specified by the PEX manufacturer. Supports should be used to facilitate rigid bends and to alleviate stress on PEX joints when bends are needed in close proximity to such joints. 10.2.2 Tighter bends may be used when the PEX tubing is uniformly bent (supported) around a curved bracket or other rigid fixture. In this case, the minimum outside radius of the supported bend shall be as specified by the PEX manufacturer.

10.3 Directional Fittings ¶

Directional fittings (e.g., 90º and 45º elbows) should only be installed where necessary. Note: The flexible nature of PEX tubing allows for sweeping bends resulting in less fittings and joints.

10.4 Direct Burial ¶

PEX tubing and fittings may be used in direct burial applications when allowed in the manufacturer’s written installation instructions.

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Note: AWWA C904 should be consulted for water service applications.

10.5 Fire-Resistive Construction ¶

Manufacturer’s installation instructions shall be consulted prior to installation of PEX tubing in fire resistive constructions. PEX tubing penetrating a wall or floor-and-ceiling fire-rated assembly shall include a means of passive fire protection in accordance with the local codes.

10.6 Sizing and Flow Velocities ¶

10.6.1 PEX tubing shall be sized in accordance with IAPMO/ANSI UPC 1.

Note: Potable water piping sizing is addressed in Chapter 6 and Appendix A of IAPMO/ANSI UPC 1. 10.6.2 The tubing manufacturer’s pressure-loss data should be referenced when using Appendix A of IAPMO/ANSI UPC 1. In absence of such data, Figures 3 and 4 shall be used.

10.6.3 Flow velocities through the water distribution system, used for calculating flush tank and flush valve fixture units depending on the tubing sizes (see Table 1), shall not exceed

(a) 3.0 m/s (10 ft/s) for cold-water distribution systems; and (b) 2.4 m/s (8 ft/s) for hot-water distribution systems. Note: The flow velocities in Items (a) and (b) account for the increased velocities through the fit- tings. 10.6.4 Hot-water recirculation systems shall

(a) be balanced to maintain adequate system temperatures; and (b) have flow velocities that do not exceed 0.6 m/s (2 ft/s) (see Table 2); and (c) use only PEX tubing designated for hot, chlorinated water recirculation systems and rated for the maximum percentage of time during which the system is intended to be operated at elevated temperatures, in accordance with ASTM F876.

10.7 Installation Testing ¶

Installation of PEX water distribution systems may be tested with air when

(a) expressly allowed in the written instructions of the manufacturers of all plastic pipe and fittings installed at the time the PEX piping system is being tested; and (b) compressed air or other gas testing is not prohibited by the authority having jurisdiction.

Note: LB = C × √ (D × Δ L)

where

LB = length of flexible arm

C = material constant (12 for PEX)

D = nominal outside diameter of tubing

Δ L = thermal expansion length

FIGURE 1

EXPANSION ARMS

(See Sections 6.4.1 and 7.3)

IS 31

TABLE 1

CALCULATION OF FLUSH TANK AND FLUSH VALVE FIXTURE UNITS

(See Section 10.6.3)

NOMINAL TUBING SIZE	FLOW VELOCITY: 3.0 m/s (10 ft/s)			FLOW VELOCITY: 2.4 m/s (8 ft/s)
NOMINAL TUBING SIZE	FLOW VOLUME, L/min (gpm)	FLUSH TANK FIXTURE UNITS	FLUSH VALVE FIXTURE UNITS	FLOW, L/min (gpm)	FLUSH TANK FIXTURE UNITS	FLUSH VALVE FIXTURE UNITS
1⁄2	20.8 (5.5)	6	—	16.7 (4.4)	4	—
3⁄4	41.6 (11.0)	15	—	33.3 (8.8)	11	—
1	68.9 (18.2)	26	—	55.3 (14.6)	20	—
11⁄4	103.0 (27.2)	46	10	82.5 (21.8)	33	5
11⁄2	143.5 (37.9)	77	24	114.7 (30.3)	54	13
2	246.1 (65.0)	200	91	196.8 (52.0)	135	52
3	533.0 (140.8)	590	495	426.2 (112.6)	443	310

TABLE 2

TUBING SIZES, FLOWS, AND FRICTION LOSSES FOR HOT-WATER RECIRCULATION SYSTEMS

(See Section 10.6.4)

NOMINAL TUBING SIZE	FLOW VELOCITY m/s (ft/s)	FLOW VOLUME L/min (gpm)	FRICTION LOSSES AT 49ºC (120ºF) kPa/m (psi/ft)
1⁄2	0.6 (2)	4.2 (1.1)	0.4411 (0.0195)
3⁄4	0.6 (2)	8.3 (2.2)	0.2850 (0.0126)
1	0.6 (2)	13.6 (3.6)	0.2081 (0.0092)
11⁄4	0.6 (2)	20.4 (5.4)	0.1629 (0.0072)
11⁄2	0.6 (2)	28.4 (7.5)	0.1335 (0.0059)
2	0.6 (2)	48.8 (12.9)	0.0950 (0.0042)

Note:

LB shall be calculated as specified in Figure 2 and divided into three sections, as follows: LB = L1 + (2 × L2)

where

L1 = LB ÷ 5; and

L2 = L1 × 2.

FIGURE 2

EXPANSION LOOPS

(See Sections 6.4.2 and 7.3)

460 2025 CALIFORNIA PLUMBING CODE

IS 31

FIGURE 3

PRESSURE LOSS OF PEX TUBING AT 16 ºC (60ºF) (See Section 10.6.2)

IS 31

FIGURE 4 PRESSURE LOSS OF PEX TUBING AT 49 ºC (120ºF)

(See Section 10.6.2)

462 2025 CALIFORNIA PLUMBING CODE

THRUST BLOCKING FOR RUBBER GASKETED AND

SOLVENT CEMENT JOINTS

IAPMO IS 33-2019 [e2]

The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.

1 Scope

1.1 General

1.1.1 This Standard specifies requirements for the installation of thrust blocking for ductile iron pipe with elastomeric gasketed joints and fittings and PVC piping with solvent cemented or elastomeric gasketed joints intended for cold water building supply and yard piping.

1.1.2 Thrust blocks covered by this standard prevent separation of joints and pipe movement by transferring the resultant thrust force at a bend to the undisturbed soil behind the thrust block. The bearing strength of the soil is expressed in pounds per square foot. Therefore, the area behind the thrust block must engage enough soil area to resist the resultant thrust force at a change in direction. 1.2 Terminology

In this Standard,

(a) “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy to comply with the Standard;

(b) “should” is used to express a recommendation, but not a requirement;

(d) “can” is used to express a possibility or a capability.

1.3 Amendments

Proposals for amendments to this Standard will be processed in accordance with the standards-writing procedures of IAPMO.

2 Reference Publications

This Standard refers to the following publications, and where such reference is made, it shall be to the current edition of those publications, including all amendments published thereto.

IAPMO/ANSI UPC-1 Uniform Plumbing Code

3 Abbreviations

The following abbreviations apply in this Standard:

PVC — polyvinyl chloride

4 General

4.1 Thrust Blocking for Rubber Gasket Joints

In lines with rubber gasketed joints, thrust blocks shall be installed at all locations including:

(a) Changes in direction, as at tees and bends

(b) Changes in size, as at reducers

(d) Valves, where thrusts may be expected.

Note: See examples in Figure 1. 4.2 Sizing

Piping shall be sized in accordance with the applicable code or jurisdictional requirements.

Note: For example, Appendix A, “Recommended Rules for Sizing the Water Supply System”, or Section 610.0, “Size of Potable Water Piping” of IAPMO/ANSI UPC-1 may be use for sizing pipe.

4.3 Flow Velocity

Flow velocity shall not exceed 8 fps (2.4 m/s) for PVC pipe or 10 fps (3m/s) for other pipe materials.

4.4 Deflection

Elastomeric gasketed pipe may be deflected in accordance with the manufacturer’s recommendations pro

IS 33

vided that it shall not be permanently staked or blocked to maintain this deflection.

4.5 Maximum Working Pressure

The pipe and fitting system shall be designed for the maximum working pressure in accordance with Table 1.

5 Thrust Blocking Sizing and Calculations

5.1 Sizes

Thrust block sizes shall be based on the maximum line pressure, pipe size and the safe bearing load of the soil.

5.2 Calculation Examples

5.2.1 Thrust

5.2.1.1 Example 1

From Table 2, Thrust at Fittings in pounds at 100 psi of Water Pressure, the thrust for a NPS 4 Dead End Tee at a pressure of 100 psi is 1620 lb.

5.2.1.2 Example 2

The thrust for an NPS 4, Dead End Tee, at a pressure of 150 psi is 2430 lb or 1.5 times the thrust found in Table 2.

The calculation is as follows:

(a) The thrust from Table 2, for an NPS 4, Dead End Tee, at 100 psi, is 1,620 lb.

(b) The actual pressure of the system is 150 psi.

(d) Multiply the thrust from Table 2, for an NPS 4, Dead End Tee, at 100 psi, times the ratio of the actual/table pressure, or 1.5 times 1620 lb for a thrust of 2430 lb.

5.2.1.3 Example 3

From Table 3, Thrust at Fittings in Newtons at 689 kPa of Water Pressure, the thrust for a DN 125, 90° Bend, at a pressure of 689 kPa is 15,757 N.

5.2.1.4 Example 4

The thrust for a DN 125, 90° Bend, at a pressure of 861 kPa is 19,469 N or 1.25 times the force in Table 3.

The calculation is as follows

(a) The thrust from Table 3, for a DN 127, 90° Bend at a pressure of 689 kPa, is 15,575 N.

(b) The actual pressure of the system is 861 kPa.

(d) Multiply the thrust from Table 2, for a DN 125, 90° Bend, at a pressure of 689 kPa times, the ratio of the actual/table pressure, or 1.25 times 15,757 N for a thrust of 19,469 N.

Note: 1000 N is equal to 1 kN for a thrust of 19.469 kN.

5.2.2 Thrust Block Bearing Area

The thrust block bearing area is determined by dividing the thrust by the safe bearing load of the soil.

Note: See examples in Figure 2

5.2.2.1 Example 5

From Table 4, Safe Bearing Loads of Various Soils the safe bearing load of sand is 2000 lb/ft [2] .

5.2.2.2 Example 6

The thrust block bearing area for an NPS 4, Dead End Tee, at a pressure of 100 psi in sand is 0.81 ft [2] .

The calculation is as follows

(a) From Table 2, Thrust at Fittings in pounds at 100 psi of Water Pressure, the thrust for a 4 in Dead End Tee at a pressure of 100 psi is 1620 lb.

(b) From Table 4 the safe bearing load of sand is 2000 lb/ft [2] .

(c) Divide the thrust by the safe bearing load of sand, or 1620 lb/2000 lb/ft [2] for a thrust block bearing area of 0.81 ft [2] .

5.2.2.3 Example 7

The thrust block bearing area for an NPS 4, Dead End Tee at a pressure of 150 psi in sand is 1.22 ft [2] .

The calculation is as follows:

(a) The thrust for an NPS 4, Dead End Tee, at a pressure of 150 psi was found in Example 2 to be 2430 lb.

(b) The soil type is sand and the safe bearing load of sand from Table 4 is 2000 lb/ft [2] .

(c) The required bearing area of the thrust block is determined by dividing the thrust by the safe bearing load or 2430 lb/2000 lb/ft [2] for a thrust block bearing area of 1.22 ft [2] .

5.2.2.4 Example 8

The thrust block bearing area for a DN 125, 90° Bend, at a pressure of 861 kPa in Soft Clay is 2.82 m [2]

The calculation is as follows:

(a) The thrust for a DN 125, 90° Bend at a pressure of 861 kPa was found in Example 4 to be 19,469 N.

(b) The soil condition is soft clay and the safe bearing load of soft clay from Table 4 is 48 kPa or 48,000 N/m [2] .

Note: 1 kPa = 1 kN/m [2 ] = 1000 N/m [2]

(c) The required block bearing area is determined by dividing the thrust by the safe bearing load or 19,469 N/48,000 N/ m [2] for a thrust block bearing area of 0.4 m [2] .

464 2025 CALIFORNIA PLUMBING CODE

IS 33

6 Testing Requirements

6.1 Rubber Gasketed Joints

Properly sized thrust blocks, either permanent or temporary, shall be installed at all required points before testing. When concrete thrust blocks are installed, wait at least 24 hours before pressure testing.

6.2 Solvent Cement Joints

The entire system shall be purged before testing to eliminate all solvent cement vapors and air. The system shall not be pressurized until the joints have cured (set) at least as long as recommended by the manufacturer. If the manufacturers recommendation is not available the cure times in Table 5 shall apply. Systems with solvent cement joints shall be pressure tested filled with water or other fluid. CAUTION: Water Test Only.

7 Identification

A label shall be fastened to the main electrical meter panel stating, “This structure has a nonmetallic water service”.

TABLE 1

MAXIMUM WORKING PRESSURE FOR PIPE AND FITTING SYSTEM DESIGN (See Section 4.5)

MAXIMUM WORKING PRESSURE kPa (psi)	SIZES		PIPE	FITTINGS
MAXIMUM WORKING PRESSURE kPa (psi)	NPS	DN	DN	DN
1103 kPa (160 psi)	1/2 to 8	15 to 200	SDR 26	Schedule 40
1103 kPa (160 psi)	1/2 to 8	15 to 200	SDR 26	Schedule 80
1379 kPa (200 psi)	1/2 to 4	15 to 100	SDR 21	Schedule 40
1379 kPa (200 psi)	1/2 to 8	15 to 200	15 to 200	Schedule 80
1724 kPa (250 psi)	1/2 to 3	15 to 80	SDR 17	Schedule 40
1724 kPa (250 psi)	1/2 to 8	15 to 200	15 to 200	Schedule 80
2172 kPa (315 psi)	1/2 to 1-1/2	15 to 40	SDR 13.5	Schedule 40
2172 kPa (315 psi)	1/2 to 4	15 to 100	15 to 100	Schedule 80
1103 kPa (160 psi)	5 to 8	125 to 200	Schedule 40	Schedule 40
1517 kPa (220 psi)	2 to 4	50 to 100	Schedule 40	Schedule 40
1517 kPa (220 psi)	2 to 4	50 to 100	Schedule 40	Schedule 80
2206 kPa (320 psi)	1/2 to 1-1/2	15 to 40	Schedule 40	Schedule 40
2206 kPa (320 psi)	1/2 to 1-1/2	15 to 40	Schedule 40	Schedule 80
1103 kPa (160 psi)	5 to 8	125 to 200	Schedule 80	Schedule 40
1517 kPa (220 psi)	2 to 4	50 to 100	Schedule 80	Schedule 40
2206 kPa (320 psi)	1/2 to 1-1/2	15 to 40	Schedule 80	Schedule 40
1724 kPa (250 psi)	5 to 8	125 to 200	Schedule 80	Schedule 80
2206 kPa (320 psi)	1/2 to 4	15 to 100	Schedule 80	Schedule 80

IS 33

TABLE 2 THRUST AT FITTINGS IN POUNDS AT 100 psi OF WATER PRESSURE (See Sections 5.2.1.1, 5.2.1.2, and 5.2.2.2)

PIPE SIZE NPS	90° BENDS	45° BENDS	22-1/2° BENDS	DEAD ENDS AND TEES
1-1/2	415	225	115	295
2	645	350	180	455
2-1/2	935	510	260	660
3	1395	755	385	985
3-1/2	1780	962	495	1260
4	2,295	1245	635	1620
5	3,500	1900	975	2,490
6	4,950	2,710	1385	3,550
8	8,300	4,500	2,290	5,860
10	12,800	6,900	3,540	9,050
12	18,100	9,800	5,000	12,800

TABLE 3 THRUST AT FITTINGS IN NEWTONS (N) AT 689 kPa OF WATER PRESSURE (See Sections 5.2.1.3, and 5.2.1.4)

PIPE SIZE DN	90° BENDS	45° BENDS	22-1/2° BENDS	DEAD ENDS AND TEES
40	1847	1000	515	1315
50	2870	1560	800	2025
65	4160	2270	1160	3940
80	6210	3360	1715	4385
90	7925	4280	2205	5610
100	10,215	5540	2815	7210
125	15,575	8455	4340	11,080
150	22,030	12,060	6165	15,800
200	36,935	20,025	10,190	26,080
250	56,960	30,705	15,755	40,275
300	80,545	43,610	22,250	56,960

466 2025 CALIFORNIA PLUMBING CODE

IS 33

TABLE 4

SAFE BEARING LOADS OF VARIOUS SOILS (See Sections 5.2.2.1, and 5.2.2.3 and 5.2.2.4)

	Safe Bearing Load
SOIL	lbs/ft2 (psf)	kN/m2 (kPa)
Mulch, Peat, etc.	0	0
Soft Clay	1000	48
Sand	2000	96
Sand and Gravel	3000	143
Sand and Gravel Cement with Clay	4000	191
Hard Shale	10,000	478

TABLE 5 MINIMUM CURE TIME, IN HOURS (h)* TEST PRESSURE FOR PIPE (See Section 6.2)

	DN 15 TO 32 (NPS 1/2 TO 1-1/4)		DN 40 TO 80 (NPS 1-1/2 TO 3)		DN 80 TO 200 (NPS 3-1/2 TO 8)
	DN 15 (NPS 1/2)	DN 32 (NPS 1-1/2)	DN 40 (NPS 1-1/2)	DN 80 (NPS 1-1/2)	DN 90 (NPS 3-1/2)	DN 200 (NPS 8)
TEMPERATURE RANGE DURING CURE PERIOD	UP TO 1240 kPa (180 PSI)	ABOVE 1240 TO 2549 kPa (180 TO 370 psi)	UP TO 1240 kPa (180 PSI)	ABOVE 1240 TO 2549 kPa (180 TO 370 psi)	UP TO 1240 kPa (180 PSI)	ABOVE 1240 TO 2549 kPa (180 TO 370 psi)
60°F - 100°F (16°C-38°C)	1 h	6 h	2 h	12 h	6 h	24 h
40°F-60°F (4°C-16°C)	2 h	12 h	4 h	24 h	12 h	48 h
10°F- 40°F (-12°C+4°C)	8 h	48 h	16 h	96 h	48 h	8 days
*If gaps or loose fits are encountered in the system, double these cure times.

IS 33

FIGURE 1

LOCATION OF THRUST BLOCKS (STANDARD AND METRIC COMBINED) A COMPARISON OF THRUST-BLOCK AREAS (See Section 4.1)

468 2025 CALIFORNIA PLUMBING CODE

IS 33

FIGURE 2

THRUST BLOCK BEARING AREA (See Section 5.2.2)

IS 33

Uniform Plumbing Code References for Ductile Iron and PVC Pressure Building Supply and Exterior Cold-Water Piping

The following sections of the 2024 Uniform Plumbing Code apply to ductile iron and PVC pressure building supply and exterior cold-water piping.

Chapter 3 General Regulations

309.0 Workmanship

312.0 Protection of Piping, Materials, and Struc tures

313.0 Hangers, Supports, and Anchors

314.0 Trenching, Excavation, and Backfill

Chapter 6 Water Supply and Distribution

604.0 Materials (water piping)

Table 604.1 Materials for Building Supply and Water Distribution Piping and Fittings

605.4 Ductile Iron Pipe and Joints

605.12 PVC Plastic Pipe and Joints

605.16.2 Plastic Pipe to Other Materials

609.0 Installation, Testing, Unions, and Location

Abbreviations

IAPMO International Association of Plumbing and Mechanical Officials

UPC Uniform Plumbing Code published by IAPMO

AWWA American Water Works Association

CSA Canadian Standards Association

Applicable Standards.

ASME B16.4 Gray Iron Threaded Fittings Classes 125 and 250

ASTM D1785 Poly (Vinyl Chloride) (PVC) Plastic Pipe, Schedules 40, 80, and 120

ASTM D2241 Poly (Vinyl Chloride) (PVC) Pressure-Rated Pipe (SDR Series)

ASTM D2466 Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 40

ASTM D2467 Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 80

ASTM F1970 Special Engineered Fittings, Appurtenances or Valves for use in Poly (Vinyl Chloride) (PVC) or Chlorinated Poly (Vinyl Chloride) (CPVC) Systems

AWWA C110 Ductile Iron and Gray-Iron Fittings

AWWA C111 Rubber-Gasket Joints for Ductile-Iron Pressure Pipe and Fittings

AWWA C151 Ductile-Iron Pipe, Centrifugally Cast

AWWA C153 Ductile-Iron Compact Fitting

AWWA C900 Polyvinyl Chloride (PVC) Pressure Pipe and Fabricated Fittings, 4 in. through 12 in. (100 mm through 300 mm)

AWWA C904 Crosslinked Polyethylene (PEX) Pressure Tubing, ½ in. through 3 In. (13 mm through 76 mm), for Water Service

AWWA C907 Injection-Molded Polyvinyl Chloride (PVC) Pressure Fittings, 4 In, through 12 in (100 mm through 300 mm) for Water, Wastewater and Reclaimed Water Service

IAPMO/

ANSI UPC-1 Uniform Plumbing Code

470 2025 CALIFORNIA PLUMBING CODE

The information contained in this appendix is not part of this American National Standard (ANS) and has not been processed in accordance with ANSI's requirements for an ANS. As such, this appendix may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements necessary for conformance to the standard.

The following Sections B414-22, B417-22, B421C-22, B422C-22, SR614-22, TR41822, TR420-22, are excerpted in their entirety from the 2022 Handbook for the Instal- lation of Ceramic, Glass, and Stone Tile Installations, with permission from the Tile Council of North America, Inc.

In addition to these, the TCNA Handbook, includes 200+ methods for tile and stone installation based on various installation requirements and application types, as well as product selection guides, field and installation requirements, and guidelines for wet areas. For a complete copy, visit www.TCNAtile.com.

For the following standards, refer to the complete copy of the 2022 TCNA Handbook for Ceramic, Glass, and Stone Tile Installations : B441-22 [Wood or Metal Studs, Backer Board, Mortar Bed Walls (One Coat Method), Mortar Bed Floor, Ceramic Tile]; B415-22 (Wood or Metal Studs, Cement Backer Board or Fiber-Cement Backer Board Walls, Mortar Bed Floor, Ceramic Tile, Glass Tile); B420-22 (Wood or Metal Studs, Coated Glass Mat Water-Resistant Gypsum Backer Board Walls, Mortar Bed Floor, Ceramic Tile, Glass Tile); B426-22 (Wood or Metal Studs, Cementitious-Coated Extruded Foam Backer Board Walls, Mortar Bed Floor, Ceramic Tile, Glass Tile); B431-22 (Wood or Metal Studs, Fiber-Reinforced Water-Resistant Gypsum Backer Board Walls, Mortar Bed Floor, Ceramic Tile, Glass Tile); B421-22 (Solid Backing, Bonded Waterproof Membrane, Ceramic Tile, Glass Tile); and B422-22 (Solid Backing, Bonded Waterproof Membrane, Integrated).

2022 TCNA HANDBOOK

FOR CERAMIC, GLASS, AND

STONE TILE INSTALLATION

The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.

TCNA HANDBOOK

NOTICE OF DISCLAIMER AND LIMITATION OF LIABILITY

This publication is provided as a guide, and all of the information it contains is provided ‘as is’ without warranty of any kind, whether express or implied. All implied warranties, including, without limitation, implied warranties of merchantability, fitness for a particular purpose, and non-infringement, are hereby expressly disclaimed.

Publisher expressly disclaims any obligation to obtain and include information other than that presented herein resulting from the handbook committee consensus process. This information does not purport to address safety issues or applicable regulatory requirements associated with its use. It is the responsibility of the user of this information to review any applicable codes and other regulations and any site specific conditions in connection with the use of this information. Publisher expressly makes no representations or warranties regarding use of this information and compliance with any applicable statute, rule or regulation.

The reader is expressly warned to consider and adopt all safety precautions appropriate for the activities herein and to avoid all potential hazards. Such precautions are generally not listed herein and are outside the scope of this document.

Under no circumstances will publisher be liable to any person or business entity for any damages, including without limitation any and all direct, indirect, special, incidental, consequential, or exemplary damages, resulting, in whole or in part, from any use of, reference to, or reliance upon this publication, even if advised of the possibility of such damages. The foregoing limitation of liability is a fundamental element of the use of this information and the information would not be offered by the publisher without such limitation.

472 2025 CALIFORNIA PLUMBING CODE

SHOWER RECEPTORS TCNA HANDBOOK

Recommended Uses

For showers that do not have prefabricated receptors.
For areas where wall flatness is critical, such as when tiles with any edge longer than 15" are specified.

Environmental Exposure Classifications

Res1, 2, 3, 5; Com1, 2, 3, 5.
For Res4 and Com4, see SR614.
For installations that may be exposed to staining, specify tile and grout suitable for exposure. Consult product manufacturers; see also “Product Selection Guides.”
For installations that may be exposed to mild chemical attack, specify epoxy grout and tile suitable for exposure. For greater resistance to chemical exposure, also specify an

epoxy bonding material. Consult product manufacturers; see also “Product Selection Guides.”

Limitations

Maximum mortar bed thickness with scratch coat (wood or metal studs) not to exceed 1 [1] ⁄ 2 ".
Maximum stud spacing 16" on center.

Membrane Options

A vapor retarder membrane (A108.02-3.8) is required in order to prevent moisture intrusion and protect adjacent building materials.
A waterproof membrane (A118.10) may be additionally specified for walls to further prevent moisture intrusion and protect adjacent building materials. Specifier shall indicate if complete waterproofing of walls is required, including treatment at termination points.
Check with membrane manufacturer for suitability for applicable conditions, as not all membranes are suitable for steam, high-temperature and/or chemical exposure, or exterior use.
When glass tile is used, consult glass tile manufacturer for membrane options and recommendations.

Requirements

Wood studs—dry and well-braced, minimum depth 3½".
Metal studs—well-braced; 20 gauge (0.033") or heavier; minimum depth 3 [1] ⁄ 2 " for residential applications or 3 [5] ⁄ 8 " for commercial applications.
Mortar bed thickness (with scratch coat)— [3] ⁄ 4 " minimum to 1½ “ maximum (wood or metal studs).
Vapor retarder membrane behind mortar bed must lap over shower pan membrane.
Slope shower pan membrane [1] ⁄ 4 " per foot to weep holes in drain.
Turn shower pan membrane up walls a minimum of 3" above shower curb (6" above floor in showers without curbs).
Surround drain with pea gravel or other weep protection to prevent mortar from blocking weep holes.

Materials

• Multiple options exist for membranes, mortars, grouts, and other materials and must be clearly specified to be included. If not specifically indicated, optional materials are not included and mortar/grout choice defaults to minimum performance specification indicated. Con- sider each system component and intended use to deter- mine minimum requirements and to specify options.

Ceramic tile—ANSI A137.1.
Glass tile, when used—ANSI A137.2; see also “Glass Tile Selection and Installation Guide,” and consult tile manufacturer for environmental exposure classification recommendations. Not all glass tiles are suitable.
Cementitious grout—ANSI A118.6 or better or ISO CG1 or better. When glass tile is used, specify grout designated by tile and grout manufacturers.

TCNA HANDBOOK SHOWER RECEPTORS

Epoxy grout, when used—ANSI A118.3 or ISO RG.
Cementitious bond coat—portland cement paste on a mortar bed that is still workable. For a cured mortar bed, follow recommendations below to select appropriate bonding mor tar:
When a waterproof membrane is not used—ANSI A118.1 or better or ISO C1 or better.
When a waterproof membrane is used—ANSI A118.4 or better or ISO C2S1 or better unless ANSI A118.1 or ISO C1 is recommended by membrane manufacturer.
When porcelain tile is used—ANSI A118.4 or better or ISO C2 or better.
When glass tile is used, specify mortar designated by tile and mortar manufacturers. Bond coat color will impact the final appearance of translucent glass tile. Specifier shall confirm bond coat color is acceptable.
Epoxy bond coat, when used—ANSI A118.3 or ISO R1 or better.
When glass tile is used, specify epoxy bond coat designated by tile and bond coat manufacturers. Bond coat color will impact the final appearance of translucent glass tile. Specifier shall confirm bond coat color is acceptable.
Vapor retarder membrane—ANSI A108.02-3.8.
Waterproof membrane, when used—ANSI A118.10.
Mortar bed, metal lath, and cleavage membrane— ANSI A108.1A.
Flexible mildew-resistant sealant—ASTM C920.
Shower pan membrane—local building code.
Metal studs—ASTM C645.

Materials for Green/Sustainable Design

See “Green Building Standards and Green Product Selection Guide” and consult manufacturers and suppliers for product sustainability and contribution to green building design.
Consider specifying tile and installation materials that meet ANSI A138.1, the American National Standard Specifica- tions for Sustainable Ceramic Tiles, Glass Tiles, and Tile Installation Materials .

Preparation by Other Trades

Wall framing shall meet the general framing requirements of ANSI A108.11-4.0–4.3.
Apply blocking between the studs to support the shower pan membrane.

Movement Joint (architect must specify type of joint and show location and details on drawings)

Movement joints—mandatory according to EJ171.
When glass tile is used, adhere to more frequent placement recommendations within the ranges listed in EJ171.

Installation Specifications

Shower pan membrane—ANSI A108.01-3.6.
Tile—ANSI A108.1A, .1B, or .1C. A108.1B required if waterproof membrane or epoxy bond coat to be used.
Glass tile—ANSI A108.14, .15, .16, or manufacturer’s directions.
Cementitious grout—ANSI A108.10.
Epoxy mortar/grout—ANSI A108.6.
Waterproof membrane—ANSI A108.13.
Movement Joints—EJ171 and ASTM C1193.

Notes

Test shower pan membrane and drainage fitting for leaks before commencing tilework.
Materials adversely affected by moisture in areas immediately adjacent to showers, tubs, and roman tubs should be properly protected.
A sloped portland cement mortar fill or approved preformed slope may be used under shower pan membrane when subfloor is not sloped to drain.
All horizontal surfaces, for example shower seats, sills, curbs, etc., must slope towards drain or other surface sloped toward drain. Where present, waterproofing also must be sloped.
When glass tile is used, see “Glass Tile Selection and Installation Guide,” and consult manufacturer for recommendations and requirements.
For curbless shower receptor, see B421C and B422C.

474 2025 CALIFORNIA PLUMBING CODE

TILE TUBS AND FOUNTAINS TCNA HANDBOOK

Requirements

                          - Waterproof membrane—slope membrane [1] ⁄ 4 " per foot to

weep holes in drain.

Wood framing, when used, should be pressure treated and designed to resist deflection and movement. Preparation by Other Trades

                                - Test tank, membrane, and drainage fittings for leaks before

starting tilework. Materials for Green/Sustainable Design

                              - See “Green Building Standards and Green Product Selection Guide” and consult manufacturers and suppliers for

product sustainability and contribution to green building design.

                                   - Consider specifying tile and installation materials that meet

ANSI A138.1, the American National Standard Specifications for Sustainable Ceramic Tiles, Glass Tiles, and Tile Installation Materials.

Installation Methods

                                  - Attach metal lath only above water line.

                              - Floor—follow F121.

                            - Walls—follow W221.

Installation Specifications

                            - Tile—ANSI A108.1A, 1B, 1C.

                              - Glass tile—ANSI A108.14, .15, .16, or manufacturer’s

directions.

                           - Grout—ANSI A108.10.

                          - Movement Joints—EJ171 and ASTM C1193.

TCNA HANDBOOK CURBLESS SHOWER RECEPTORS

Recommended Uses

For construction of a shower without a curb.

Environmental Exposure Classifications

Res1, 2, 3; Com1, 2
May be suitable for Com3, Res5, and Com5 as determined by membrane and backing material manufacturers.
For Res4 and Com4, see SR613 and SR614.
For installations that may be exposed to staining, specify tile and grout suitable for exposure. Consult product manufacturers; see also “Product Selection Guides.”
For installations that may be exposed to mild chemical attack, specify epoxy grout and tile suitable for exposure. Consult product manufacturers; see also “Product Selection Guides.”

Limitations

Facilitates construction of a curbless shower without adding floor height at restroom entryway, but does not inherently comply with Americans with Disabilities Act (ADA) Standards for Accessible Design. Follow ADA where ADA compliance is required or desired.
Refer to appropriate wall method for applicable limitations based on type of backing used—W201, W202E, W202I, W211, W221, W222, W231/W241, W243, W244C, W244E, W244F, W245, W246, and W247.

Requirements

When glass tile is used, consult glass tile manufacturer for tile suitability over non-absorptive surface.
Bonded waterproof membrane must be continuous, including at changes in plane. Follow membrane manufacturer’s requirements for corners, seaming, and overlap.
Waterproof membrane inside shower area must extend to full height of tile assembly. Also, the floor and wall waterproofing must continue outside the immediate shower area one foot beyond the high point of the floor, but not beyond the tiled area. Additional waterproofing of floor and/or walls outside the shower area may be needed to effectively contain and evacuate shower water and splash water and to protect building materials. When additional waterproofing of floor and/or walls outside the shower area is desired or

required, the building design professional must specify all areas to be waterproofed and indicate membrane termination points.

A secondary drain may be required outside the immediate shower area to facilitate evacuation of shower water and

splash water that is not contained in the shower area due to curbless design. When required or desired, building design professional must specify type and location of secondary drain.

High point of the floor must be outside the shower area, i.e., beyond shower door or curtain, to facilitate evacuation of shower water and splash water that is not contained in the shower area due to curbless design. Location of the high point of the floor is especially critical when secondary drain is not included outside the shower area.
Surround drain with pea gravel or other weep protection to prevent mortar from blocking weep holes.

476 2025 CALIFORNIA PLUMBING CODE

CURBLESS SHOWER RECEPTORS TCNA HANDBOOK

Refer to appropriate wall method for applicable requirements based on type of backing used.
Slope mortar bed [1] ⁄ 4 " per foot toward drain and follow membrane manufacturer’s instructions for connecting membrane to drain.

Materials

Ceramic tile—ANSI A137.1.
Glass tile, when used—ANSI A137.2; see also “Glass Tile Selection and Installation Guide,” and consult tile manufacturer for environmental exposure classification recommendations. Not all glass tiles are suitable.
Cementitious grout—ANSI A118.6 or better or ISO CG1 or better. When glass tile is used, specify grout designated by tile and grout manufacturers.
Epoxy grout, when used—ANSI A118.3 or ISO RG.
Cementitious bond coat:
ANSI A118.4 or better or ISO C2S1 or better unless ANSI A118.1 or ISO C1 is recommended by membrane manufacturer.
When glass tile is used, specify mortar designated by tile and mortar manufacturers. Bond coat color will impact the final appearance of translucent glass tile. Specifier shall confirm bond coat color is acceptable.
Waterproof membrane—ANSI A118.10 and recommended by manufacturer of membrane for use over backing type in intended application.
Flexible mildew-resistant sealant—ASTM C920.

Materials for Green/Sustainable Design

See “Green Building Standards and Green Product Selection Guide” and consult manufacturers and suppliers for product sustainability and contribution to green building design.
Consider specifying tile and installation materials that meet ANSI A138.1, the American National Standard Specifica- tions for Sustainable Ceramic Tiles, Glass Tiles, and Tile Installation Materials .

Preparation by Other Trades/Backer Board Installers

Depressed slab by others. Depressed area must extend beyond shower area to facilitate a finished floor installation that effectively evacuates shower water and splash water, which are often difficult to contain within a curbless

shower.

Refer to appropriate wall method for applicable preparations by other trades and backer board installers.
Maximum allowable variation in the tile substrate—for tiles with all edges shorter than 15", maximum allowable variation is [1] ⁄ 4 " in 10' from the required plane, with no more than 1 ⁄ 16 " variation in 12" when measured from the high points in

the surface. For tiles with at least one edge 15" in length, maximum allowable variation is [1] ⁄ 8 " in 10' from the required plane, with no more than [1] ⁄ 16 " variation in 24" when measured from the high points in the surface.

Center backer board end or edge joints on framing and stagger joints in adjacent rows so four corners do not come together within the same plane. Space panel ends and edges in accordance with manufacturer’s recommendations.

Movement Joint (architect must specify type of joint and show location and details on drawings)

Movement joints—mandatory according to EJ171.
When glass tile is used, adhere to more frequent placement recommendations within the ranges listed in EJ171. Installation Specifications
Waterproof membrane—ANSI A108.13.
Tile—ANSI A108.5.
Glass tile—manufacturer’s directions.
Cementitious grout—ANSI A108.10.
Epoxy grout—ANSI A108.6.
Movement Joints—EJ171 and ASTM C1193.

Notes

Test shower pan membrane/waterproof membrane and drainage fitting for leaks before commencing tilework.
Materials adversely affected by moisture in areas immediately adjacent to showers, tubs, and roman tubs should be properly protected.
All horizontal surfaces, for example shower seats, sills, curbs, etc., must slope towards drain or other surface sloped toward drain. Where present, waterproofing also must be sloped.
When glass tile is used, see “Glass Tile Selection and Installation Guide,” and consult manufacturer for recommendations and requirements.
Follow applicable plumbing and building codes.

TCNA HANDBOOK CURBLESS SHOWER RECEPTORS

Recommended Uses

For construction of a shower without a curb.

Environmental Exposure Classifications

Res1, 2, 3; Com1, 2
May be suitable for Com3, Res5, and Com5 as determined by membrane and backing material manufacturers.
For Res4 and Com4, see SR613 and SR614.
For installations that may be exposed to staining, specify tile and grout suitable for exposure. Consult product manufacturers; see also “Product Selection Guides.”
For installations that may be exposed to mild chemical attack, specify epoxy grout and tile suitable for exposure. Consult product manufacturers; see also “Product Selection Guides.”

Limitations

Facilitates construction of a curbless shower without adding floor height at restroom entryway, but does not inherently comply with Americans with Disabilities Act (ADA) Standards for Accessible Design. Follow ADA where ADA compliance is required or desired.
Refer to appropriate wall method for applicable limitations based on type of backing used—W201, W202E, W202I, W211, W221, W222, W231/W241, W243, W244C, W244E, W244F, W245, W246, and W247.

Requirements

When glass tile is used, consult glass tile manufacturer for tile suitability over non-absorptive surface.
Bonded waterproof membrane must be continuous, including at changes in plane. Follow membrane manufacturer’s requirements for corners, seaming, and overlap.
Waterproof membrane inside shower area must extend to full height of tile assembly. Also, the floor and wall waterproofing must continue outside the immediate shower area one foot beyond the high point of the floor, but not beyond the tiled area. Additional waterproofing of floor and/or walls outside the shower area may be needed to effectively contain and evacuate shower water and splash water and to protect building materials. When additional waterproofing of floor and/or walls outside the shower area is desired or required, the building design professional must specify all areas to be waterproofed and indicate membrane termination points.
A secondary drain may be required outside the immediate shower area to facilitate evacuation of shower water and splash water that is not contained in the shower area due to curbless design. When required or desired, building design professional must specify type and location of secondary drain.
High point of the floor must be outside the shower area, i.e., beyond shower door or curtain, to facilitate evacuation of

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CURBLESS SHOWER RECEPTORS TCNA HANDBOOK

shower water and splash water that is not contained in the shower area due to curbless design. Location of the high point of the floor is especially critical when secondary drain is not included outside the shower area.

Refer to appropriate wall method for applicable requirements based on type of backing used.
Slope mortar bed [1] ⁄ 4 " per foot toward drain and follow membrane and integrated bonding flange manufacturer’s instructions for connecting membrane to integrated bonding flange.

Materials

Ceramic tile—ANSI A137.1.
Glass tile, when used—ANSI A137.2; see also “Glass Tile Selection and Installation Guide,” and consult tile manufacturer for environmental exposure classification recommendations. Not all glass tiles are suitable.
Cementitious grout—ANSI A118.6 or better or ISO CG1 or better. When glass tile is used, specify grout designated by tile and grout manufacturers.
Epoxy grout, when used—ANSI A118.3 or ISO RG.
Cementitious bond coat:
ANSI A118.4 or better or ISO C2S1 or better unless ANSI A118.1 or ISO C1 is recommended by membrane manufacturer.
When glass tile is used, specify mortar designated by tile and mortar manufacturers. Bond coat color will impact the final appearance of translucent glass tile. Specifier shall confirm bond coat color is acceptable.
Waterproof membrane—ANSI A118.10 and recommended by manufacturer of membrane for use over backing type in intended application.
Flexible mildew-resistant sealant—ASTM C920.

Materials for Green/Sustainable Design

See “Green Building Standards and Green Product Selection Guide” and consult manufacturers and suppliers for product sustainability and contribution to green building design.
Consider specifying tile and installation materials that meet ANSI A138.1, the American National Standard Specifica- tions for Sustainable Ceramic Tiles, Glass Tiles, and Tile Installation Materials .

Preparation by Other Trades/Backer Board Installers

Depressed slab by others. Depressed area must extend beyond shower area to facilitate a finished floor installation that effectively evacuates shower water and splash water, which are often difficult to contain within a curbless

shower.

Refer to appropriate wall method for applicable preparations by other trades and backer board installers.
Maximum allowable variation in the tile substrate—for tiles with all edges shorter than 15," maximum allowable variation is [1] ⁄ 4 " in 10’ from the required plane, with no more than 1 ⁄ 16 " variation in 12" when measured from the high points in the surface. For tiles with at least one edge 15" in length, maximum allowable variation is [1] ⁄ 8 " in 10' from the required plane, with no more than [1] ⁄ 16 " variation in 24" when measured from the high points in the surface.
Center backer board end or edge joints on framing and stagger joints in adjacent rows so four corners do not come together within the same plane. Space panel ends and edges in accordance with manufacturer’s recommendations.

Movement Joint (architect must specify type of joint and show location and details on drawings)

Movement joints—mandatory according to EJ171.
When glass tile is used, adhere to more frequent placement recommendations within the ranges listed in EJ171.

Installation Specifications

Waterproof membrane—ANSI A108.13.
Tile—ANSI A108.5.
Glass tile—manufacturer’s directions.
Cementitious grout—ANSI A108.10.
Epoxy grout—ANSI A108.6.
Movement Joints—EJ171 and ASTM C1193.

Notes

Test shower pan membrane/waterproof membrane and drainage fitting for leaks before commencing tilework.
Materials adversely affected by moisture in areas immediately adjacent to showers, tubs, and roman tubs should be properly protected.
All horizontal surfaces, for example shower seats, sills, curbs, etc., must slope towards drain or other surface sloped toward drain. Where present, waterproofing also must be sloped.
When glass tile is used, see “Glass Tile Selection and Installation Guide,” and consult manufacturer for recommendations and requirements.
Follow applicable plumbing and building codes.

TCNA HANDBOOK COMMON SHOWER CONFIGURATIONS

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COMMON SHOWER CONFIGURATIONS TCNA HANDBOOK

TCNA HANDBOOK STEAM SHOWER/ROOM; WOOD/METAL STUDS

Recommended Uses

For steam showers and steam rooms framed with wood or metal studs. Specify mortar bed walls option when wall flatness is critical, such as when tiles with any edge longer than 15" are specified. Environmental Exposure Classifications
Res4.
For installations that may be exposed to staining, specify tile and grout suitable for exposure. Consult product manufacturers; see also Notes and “Product Selection Guides.”

Limitations

Duration of use as a steam shower or steam room as determined by membrane and cement backer board (when used) manufacturers; lower membrane water vapor permeance decreases water vapor transmission.
Maximum stud spacing 16" on center. Requirements
Steam rooms are highly specialized applications. Design and installation are critical to avoid damage to adjoining materials from vapor migration. Design criteria must include consideration of necessary insulation and temperature and humidity differential.
Use a tile contractor knowledgeable in steam applications and experienced with the materials specified.
Bonded waterproof membrane (sheet, liquid, and trowelon) must be continuous and must adequately limit vapor transmission into adjacent spaces and building materials, according to intended duration of use as a steam shower.
Steam showers designed for continuous use applications should specify a low perm waterproof membrane (a waterproof membrane meeting ANSI A118.10 and with a water vapor permeance rating of 0.5 perms or less when tested per ASTM E96 Procedure E, tested at 90% relative humidity). When a waterproof membrane with a water vapor permeance rating greater than 0.5 perms is specified, a vapor retarder behind the wall assembly is required, and vapor retarder must have a water vapor permeance rating of 0.1 perm or less when tested per ASTM E96 Procedure A, tested at 50% relative humidity. Consult waterproof membrane manufacturer for water vapor permeance rating and vapor retarder requirements.
Specifier shall indicate how waterproofing and vapor retarding is to be achieved, including details for membrane penetrations such as penetrations for plumbing, lighting fixtures, fasteners, etc. Specifier shall also indicate where and how to waterproof curbs and jambs and where membrane terminates. Area outside steam shower door is a wet area and should be treated accordingly.
Check with membrane manufacturer for suitability for applicable conditions, as not all membranes are suitable for steam, high temperature and/or chemical exposure.
Some waterproof membrane manufacturers require use of a vapor retarder membrane in addition to the waterproof membrane. Consult membrane manufacturer for requirements. When used, vapor retarder membrane must weather lap itself and lap into the shower pan membrane.
If vapor retarder membrane is required, integrated bonding flange cannot be used.
Follow waterproof membrane manufacturers’ directions for interface between drain and membrane(s).
Design professional to specify adequate insulation on walls and ceilings to reduce condensation. Consult insulation manufacturer for application suitability.
Seal all membrane penetrations with appropriate sealant according to membrane manufacturer’s requirements.

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STEAM SHOWER/ROOM; WOOD/METAL STUDS TCNA HANDBOOK

Specify slip joints at change in plane, such as where walls and ceiling meet.
Slope ceiling minimum 2" per foot to avoid condensate dripping onto occupants; sloping ceiling from center can minimize rundown on walls.
When mortar bed walls, studs must provide firm anchorage for metal lath.
When mortar bed walls, mortar bed wall thickness— [3] ⁄ 4 " minimum to 1 [1] ⁄ 2 " maximum.
When mortar bed walls, cut lath at all slip joints.
Slope shower pan membrane minimum [1] ⁄ 4 " per foot to weep holes in drain.
Turn shower pan membrane up walls a minimum of 3" above shower curb (6" above floor in showers without curbs).
Surround drain with pea gravel or other weep protection to prevent mortar from blocking weep holes. (Does not apply if integrated bonding flange is used.)
Wood studs, when used—dry and well braced, minimum depth 3 [1] ⁄ 2 ".
Metals studs, when used—well-braced; 20 gauge (0.033") or heavier; minimum depth 3 [1] ⁄ 2 " for residential applications or 3 [5] ⁄ 8 " for commercial applications. Preparation by Backer Board Installers
Maximum allowable variation in the tile substrate—for tiles with all edges shorter than 15," maximum allowable variation is [1] ⁄ 4 " in 10' from the required plane, with no more than 1 ⁄ 16 " variation in 12" when measured from the high points in the surface. For tiles with at least one edge 15" in length, maximum allowable variation is [1] ⁄ 4 " in 10' from the required plane, with no more than [1] ⁄ 16 " variation in 24" when measured from the high points in the surface.
Horizontal joints— [1] ⁄ 8 " spacing filled solid and taped with latex-portland cement mortar and 2" alkali-resistant glass fiber mesh tape.
Vertical joints—fill any space and tape with latex-portland cement mortar and 2" alkali-resistant glass fiber mesh tape.
Corners—leave space between backer units. Tape joints using skim coat of latex-portland cement mortar, but do not fill.
Center backer board end or edge joints on framing and stagger joints in adjacent rows so four corners do not come together within the same plane. Space panel ends and edges in accordance with manufacturer’s recommendations.

Materials

Ceramic tile—ANSI A137.1 and recommended by manufacturer for use in steam showers.
Cementitious grout—ANSI A118.6 or better or ISO CG1 or better.
Epoxy grout, when used—ANSI A118.3 or ISO RG.
Cementitious bond coat:
ANSI A118.15 or better or ISO C2S1 or better, unless ANSI A118.1 or ISO C1 is recommended by membrane manufacturer.
Cement backer board, when used—ANSI A118.9 or ASTM C1325 (Type A).
Fasteners—noncorrosive and nonoxidizing.
Hot dipped fasteners meeting ASTM F2329 required in wet

areas.

2" alkali-resistant glass fiber mesh tape.
Waterproof membrane—ANSI A118.10 and recommended by membrane manufacturer for use in specific application. For continuous use applications, see Requirements for water

vapor permeance.

Vapor retarder membrane, when used—recommended by manufacturer for use in specific application.
Metal studs, when used—ASTM C645.
Shower pan membrane—ANSI A118.10, ASTM D4068, or D4551 and meeting applicable building code.
Mortar bed and reinforcing—ANSI A108.1A.
Flexible mildew-resistant sealant—ASTM C920 and recommended by manufacturer for use in steam showers. Materials for Green/Sustainable Design
See “Green Building Standards and Green Product Selection Guide” and consult manufacturers and suppliers for product sustainability and contribution to green building design.
Consider specifying tile and installation materials that meet ANSI A138.1, the American National Standard Specifications for Sustainable Ceramic Tiles, Glass Tiles, and Tile Installation Materials.

Preparation by Other Trades

Wall framing shall meet the general framing requirements of ANSI A108.11-4.0-4.3.

Movement Joint (architect must show type of joint and show location and details on drawings)

Movement joints—mandatory according to EJ171.
Slip joints at changes in plane, such as where walls and ceiling meet. Installation Specifications
Shower pan membrane—ANSI A108.01-3.6.
Mortar bed and reinforcing—ANSI A108.1A, .1B, and .1C.
Tile—ANSI A108.5.
Cementitious grout—A108.10.
Epoxy grout—A108.6.
Waterproof membrane and slip joint—ANSI A108.13 and membrane manufacturer’s slip joint directions.
Movement Joints—EJ171 and ASTM C1193.

Notes

Use of softened water in steam showers and steam rooms helps reduce grout and tile staining due to iron and/or hard water. Such stains may require harsh chemicals for removal. Select products suitable for water type and maintenance practices that will be used.
Standard grouts will need to be periodically maintained over the life of the steam shower.
Steam unit design must take into consideration the affect of moisture vapor transmission (MVT) on opposite side of steam unit walls. MVT can cause efflorescence and can affect paints and other adhered finishes.

TCNA HANDBOOK SHOWER RECEPTOR RENOVATION

Recommended Uses

For use where old shower pan has failed. Requirements
Remove existing shower receptor, shower pan, and wall tile, as required, to install new shower pan.
Replace any damaged wall and floor substrate materials.
New shower pan—slope [1] ⁄ 4 " per foot to weep holes in drain.
New shower pan to turn up wall a minimum of 3" above curb (6" above floor in showers without curbs).
New wall membrane/flashing (ANSI A108.02-3.8) placed behind existing wall membrane, out over new shower pan, and fastened to studs.
Place continuous bead of sealant on existing wall mortar with new wall mortar brought up tight against it. Materials for Green/Sustainable Design
See “Green Building Standards and Green Product Selection Guide” and consult manufacturers and suppliers for product sustainability and contribution to green building design.
Consider specifying tile and installation materials that meet ANSI A138.1, the American National Standard Specifica- tions for Sustainable Ceramic Tiles, Glass Tiles, and Tile Installation Materials .

Notes

See B414 for complete specifications.

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SHOWER RECEPTOR RENOVATION TCNA HANDBOOK

tions for Sustainable Ceramic Tiles, Glass Tiles, and Tile Installation Materials.

Notes

See B415, B420, B426, or B431 for complete specifications based on wall backing type.

Recommended Uses

- For use where old shower pan has failed.

Requirements

- Remove existing shower receptor, shower pan, and wall tile,

as required, to install new shower pan.

- Replace any damaged wall and floor substrate materials.

- New shower pan—slope ¼" per foot to weep holes in drain.

- New shower pan to turn up wall a minimum of 3" above

curb (6" above floor in showers without curbs).

- New wall membrane/flashing (ANSI A108.02-3.8) placed

behind existing wall membrane, out over new shower pan, and fastened to studs.

- Place continuous bead of sealant on existing wall substrate

material with new wall substrate material brought up tight against it.

Materials for Green/Sustainable Design

- See “Green Building Standards and Green Product Selection Guide” and consult manufacturers and suppliers for

product sustainability and contribution to green building design.

- Consider specifying tile and installation materials that meet

ANSI A138.1, the American National Standard Specifica-

486 2025 CALIFORNIA PLUMBING CODE

CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE