Polyethylene (PE)

General Information

Polyethylene (PE) is a thermoplastic material produced from the polymerization of ethylene. PE plastic pipe is manufactured by extrusion in sizes ranging from ½" to 63". PE is available in rolled coils of various lengths or in straight lengths up to 40 feet. Generally small diameters are coiled and large diameters (>6" OD) are in straight lengths. PE pipe is available in many varieties of wall thicknesses, based on three distinct dimensioning systems:

• Pipe Size Based on Controlled Outside Diameter (DR)
• Iron Pipe Size Inside Diameter, IPS-ID (SIDR)
• Copper Tube Size Outside Diameter (CTS)

PE pipe is available in many forms and colors such as the following:

• Single extrusion colored or black pipe
• Black pipe with coextruded color striping
• Black or natural pipe with a coextruded colored layer

Uses and Applications

PE pipe offers distinct advantages as a piping material:

• Light weight
• Flexibility
• Chemical resistance
• Overall toughness
• Longevity

These benefits make it an ideal piping material for a broad variety of applications such as potable water service or distribution lines, natural gas distribution, lawn sprinklers, sewers, waste disposal, and drainage lines. PE materials are generally resistant to most ordinary chemicals.

Pex Tubing

What is PEX?

PEX is cross-linked Polyethylene. Through one of several processes, links between polyethylene macromolecules are formed to create bridges between PE molecules (thus the term "cross-linked"). This resulting molecule is more durable under temperature extremes, chemical attack, and resists creep deformation, making PEX an excellent material for hot water applications (up to 200° F).

How long has PEX been used?

PEX was developed in the 1960s. PEX tubing has been in use in many European countries for plumbing, radiant heating and snow melt applications since that time. PEX was introduced in the United States in the 1980s, and has seen significant growth in market demand and production.

What are recommended uses for PEX?

PEX 's flexibility and strength at temperatures ranging from below freezing up to 200 degrees Fahrenheit makes it an ideal piping material for hot and cold water plumbing systems, hydronic radiant heating systems, snow melting applications, and, even ice rinks and refrigeration warehouses.

Why is PEX an excellent piping material for plumbing?

PEX is ideally suited for potable water plumbing applications. It is flexible, making it easy to install and service. PEX is able to withstand the high and low temperatures found in plumbing and heating applications, and is highly resistant to chemicals found in the plumbing environment. Although not freeze proof, PEX also provides the homeowner with many useful benefits. Flexible systems are quieter than rigid piping. The smooth interior resists scale buildup and corrosion that can affect long term pipe flow characteristics. PEX is also very freeze- break resistant. Finally, PEX systems have attractive installation costs when compared with rigid materials. PEX is the best piping material for many plumbing applications, but not for outdoor or UV exposed applications.

How can I be sure that PEX is a safe product for plumbing?

PEX is manufactured and tested according to stringent national consensus standards: ASTM F 876 and F 877. Both the product manufacturer and independent third party testing agencies conduct routine quality control and quality assurance evaluations to insure the product meets ASTM and NSF Standards. Compliance with the standards ensures the end user of safety and quality. Additionally, PEX is included in all of the major model plumbing codes used in the United States and Canada, CSA, IAPMO, SBCCI, BOCA, ICBO, IPC and NSPC, and approved by HUD for hot and cold potable water plumbing use.

Can PEX be used for underground cold-water service applications?

CPVC

General Information

Chlorinated Poly (Vinyl Chloride) (CPVC) is a thermoplastic pipe and fitting material made with CPVC compounds meeting the requirements of ASTM Class 23447 as defined in ASTM Specification D1784. CPVC applications are for potable water distribution, corrosive fluid handling in industry, and fire suppression systems.

CPVC piping systems are:

• Environmentally friendly
• Provide long service life
• Easy to install and handle
• Corrosion resistant
• Cost effective
• Widely accepted by codes

Industrial CPVC pipe is manufactured by extrusion in sizes from ¼" to 12" diameter to Sch 40, Sch 80, and SDR (Standard Dimension Ratio) dimensions. CPVC pipe for plumbing systems is manufactured by extrusion in sizes ¼" through 2" copper tube size (CTS) dimensions. The CTS plumbing products are made to copper tube outside diameter dimensions, in accordance with ASTM D-2846 specifications, and have an SDR 11 wall thickness. The pressure ratings of the CTS SDR 11 systems are 400 psi (pounds per square inch) at 73° F and 100 psi at 180° F. CPVC plumbing pipe is sold in both straight lengths and (in small diameters) coils.

Uses and Applications

CPVC piping which is suitable for hot and cold water distribution has a 400 psi pressure rating at room temperature, and a 100 psi pressure rating at 180° F.

Polyvinyl Chloride (PVC)

General Information

Polyvinyl Chloride (PVC) piping is the most widely used plastic piping material. PVC piping systems are:

• Environmentally sound
• Provide long service life
• Easy to install and handle
• Corrosion resistant
• Cost effective
• Widely accepted by codes

PVC pipe is manufactured by extrusion in a variety of sizes and dimensions and generally sold in 10' and 20' lengths. PVC pipe is available in both solid wall or cellular core construction. Cellular core construction involves the simultaneous extrusion of at least three layers of material into the pipe wall: a solid outer layer, a cellular core intermediate layer, and a solid inner layer. PVC pipe is made to conform to various ASTM standards for both pressure and non-pressure applications.

Uses and Applications

PVC piping is used for:

• Drain-waste-vent (DWV)
• Sewers
• Water mains
• Water service lines
• Irrigation
• Conduit
• Various industrial installations

It can be used under ground or above ground in buildings. It can also be used outdoors if the pipe contains stabilizers and UV inhibitors to shield against ultraviolet radiation and it is painted with a water-based latex paint.

PVC materials are resistant to many ordinary chemicals such as acids, bases, salts and oxidants.

Because PVC piping system components can be manufactured in a variety of colors, identification of application is easy. A common color scheme (although not universal) is:

• White for DWV and some low pressure applications
• White, blue, and dark gray for cold water piping
• Green for sewer service
• Dark gray for industrial pressure applications