CALIFORNIA PLUMBING CODE - MATRIX ADOPTION TABLE
APPENDIX I - INSTALLATION STANDARD FOR PEX TUBING SYSTEMS FOR HOT- AND COLD-WATER DISTRIBUTION
(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	CA	CEC	SL	SLC
Adopting Agency	BSC	BSC-CG	SFM	1	2	1-AC	AC	SS	SS/C	1	2	3	4	BSCC	DPH	AGR	DWR	CA	CEC	SL	SLC
Adopt Entire Chapter	X			X	X
Adopt Entire Chapter as amended (amended sections listed below)
Adopt only those sections that are listed below
Chapter/Section

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.

"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.

IAPMO IS 31-2014

1.0 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

SDR 9 CTS PEX tubing complying with ASTM F876 and pressure-rated in accordance with PPI TR-3; and
PEX fitting systems complying with
1. ASTM F877, for mechanical compression fittings and metal or plastic insert fittings with stainless steel press sleeves;
2. ASTM F1807 or ASTM F2159, for metal or plastic insert fittings with copper crimp rings;
3. ASTM F1960, for cold expansion fittings with PEX reinforced rings; or
4. ASTM F2080, for cold expansion fittings with metal compression sleeves.

1.2 Terminology

In this Standard,

"shall" is used to express a requirement, i.e., a provision that the user is obliged to satisfy to comply with the Standard;
"should" is used to express a recommendation, but not a requirement;
"may" is used to express an option or something permissible within the scope of the Standard; and
"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 figures and can be written as requirements.

1.3 Amendments

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

2.0 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 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 for SDR9 Cross-linked 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) Tubing
ASTM F2080	Standard Specification for Cold-Expansion Fittings With Metal Compression-Sleeves for Cross-Linked Polyethylene (PEX) Pipe
ASTM F2159	Standard Specification for Plastic Insert Fittings Utilizing a Copper Crimp Ring for SDR9 Cross-linked Polyethylene (PEX) Tubing and SDR9 Polyethylene of Raised with Temperature (PE-RT) Tubing
ASTM F2657	Standard Test Method for Outdoor with Weathering Exposure of Crosslinked Polyethylene (PEX) Tubing
AWWA C904	Cross-Linked Polyethylene (PEX) Pressure Tubing, ¹/₂ In. (12 mm) Through 3 In. (76 mm) for Water Service
IAPMO/ANSI UPC-I	Uniform Plumbing Code
PPI TR-3	Policies and Procedures for Developing Hydrostatic Design Basis (HDB), Pressure Design Basis (PDB), Strength Design Basis (SDB), and Minimum Required Strength (MRS) Ratings for Thermoplastic Tubing Materials or Tubing

3.0 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

4.0 General

4.1 Tubing

4.1.1

PEX tubing can be

pigmented throughout (i.e., with color);
non-pigmented (e.g., translucent or natural); or
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

the standard designation(s) of the fittings to which the tube can be joined to is included in the markings;
it bears a certification mark from an accredited certification organization; and
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

are made of brass, stainless steel, or sulfone;
consist of an insert and a copper crimp ring or a stainless steel press ring
are available in NTS-³/₈ to NTS-2.

4.2.3 Compression Fittings

Compression (i.e., transition) fittings typically

are made of brass; and
consist of
1. a nut, a compression ring, and an insert; or
2. an O-ring brass insert with a compression sleeve
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.

5.0 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:

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.
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.
If the load has shifted, has broken packaging, or shows evidence of rough treatment, each item shall be carefully inspected for damage.
The total quantities of each shipment (e.g., tubing, gaskets, fittings, and accessories) shall be checked against shipping records.
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.
No damaged material shall be disposed of. The carrier shall recommend the procedure to follow.
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-resistance, ranging from untested to 6 months of continuous 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°C (200°F).

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.

6.0 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°C (40°F) 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

loops;
offsets;
arms with rigid anchor points; and
supporting the tubing with continuous runs of CTS support channels with
1. rigid anchor points installed every 20 m (65 ft); and
2. 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°C (40°F) or greater change in temperature (operating temperature compared to ambient temperature) shall be controlled by installing

a riser clamp at the top of every other floor; and
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 expansion 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)

FIGURE 1
EXPANSION ARMS
(See Sections 6.4.1 and 7.3)

6.4.1.1

Expansion arms shall be installed as illustrated in Figure 1.

6.4.1.2

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

LB	=	C x √(D x ΔL)
where
LB	=	length of flexible arm
C	=	material constant (12 for PEX)
D	=	nominal outside diameter of tubing
ΔL	=	thermal expansion length

6.4.2 Expansion Loops (See Figure 2)

FIGURE 2
EXPANSION LOOPS
(See Sections 6.4.2 and 7.3)

6.4.2.1

Expansion loops shall be installed at the midpoint 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 x 2

7.0 Hangers and Supports

7.1 Vertical Tubing

Vertical PEX tubing shall

be supported at each floor or as specified by the water-distribution system designer to allow for expansion and contraction; and
have mid-story guides.

7.2 Horizontal Tubing

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

NTS-1 and smaller shall be supported every 0.8 m (32 in), unless continuously supported by metallic CTS or V channels that
1. are supported at intervals not exceeding 1.8 m (6 ft);
2. have a maximum cantilever, measured from the support to the end of the CTS support channel, of 0.5 m (1.5 ft); and
NTS-1¹/₄ and larger shall be supported every 1.2 m (4 ft), unless continuously supported by metallic CTS or V channels that
1. are supported at intervals not exceeding 2.4 m (8 ft); and
2. 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

used to restrict PEX tubing movement;
made of materials that provide rigidity to the support system and utilize pipe clamps designed for plastic tubing capable of restraining the tubing; and
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.

8.0 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.

9.0 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.

10.0 Other Considerations

10.1 Hot-Work Joints

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

made at least 500 mm (18 in) from PEX tubing in the same water line; and
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., 90° and 45° 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.

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.

3.0 m/s (10 ft/s) for cold-water distribution systems; and
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 fittings.

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	—
1-1/4	103.0 (27.2)	46	10	82.5 (21.8)	33	5
1-1/2	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

10.6.4

Hot-water recirculation systems shall

be balanced to maintain adequate system temperatures; and
have flow velocities that do not exceed 0.6 m/s (2 ft/s) (see Table 2); and
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.

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 49°C (120°F) 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)
1 ¹/₄	0.6 (2)	20.4 (5.4)	0.1629 (0.0072)
1 ¹/₂	0.6 (2)	28.4 (7.5)	0.1335 (0.0059)
2	0.6 (2)	48.8 (12.9)	0.0950 (0.0042)

10.7 Installation Testing

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

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
compressed air or other gas testing is not prohibited by the authority having jurisdiction.

Note:
LB	=	C x √(D x ΔL)
where
LB	=	length of flexible arm
C	=	material constant (12 for PEX)
D	=	nominal outside diameter of tubing
ΔL	=	thermal expansion length