Can You Bury Pex Fittings Underground

PEX (Polyethylene Cross-linked) fittings are a popular choice for plumbing systems due to their flexibility, durability, and resistance to corrosion. However, one question that often arises is whether PEX fittings can be buried underground. The answer is yes, but certain precautions must be taken to ensure their longevity and safety.

Types of PEX Fittings for Underground Use

Not all PEX fittings are suitable for underground burial. The most commonly used types for this purpose are:

• Type B PEX: This type of PEX has a higher density and is more resistant to environmental stresses, making it ideal for underground applications.
• PEX-AL-PEX: This type of PEX has an aluminum layer sandwiched between two layers of PEX, providing additional strength and rigidity.
• Barrier PEX: This type of PEX has an oxygen barrier layer to prevent oxygen from permeating the pipe, which can cause corrosion and premature failure.

Considerations Before Burying PEX Fittings

Before burying PEX fittings underground, several important factors need to be considered:

• Soil Conditions: The soil should be well-drained and free of sharp objects or debris that could damage the fittings.
• Depth of Burial: PEX fittings should be buried at least 18 inches below the frost line or the depth required by local building codes.
• Protection from Moisture: The fittings should be wrapped in a protective sleeve or conduit to prevent moisture from penetrating the joints.
• Pressure Rating: The pressure rating of the PEX fittings should be compatible with the water pressure in the system.
• Environmental Factors: The fittings should be protected from extreme temperatures, UV radiation, and other environmental hazards.

How to Bury PEX Fittings Underground

To bury PEX fittings underground, follow these steps:

• Excavate the Trench: Dig a trench that is deep enough to accommodate the PEX fittings and the protective sleeve or conduit.
• Install the Protective Sleeve or Conduit: Wrap the PEX fittings in a protective sleeve or conduit to prevent moisture and soil damage.
• Place the Fittings in the Trench: Carefully place the fittings in the trench, ensuring that they are properly aligned and connected.
• Backfill the Trench: Fill the trench with well-compacted soil, free of sharp objects or debris.
• Mark the Location: Use stakes or flags to mark the location of the buried fittings for future reference.

Maintenance and Troubleshooting

Once buried, PEX fittings require minimal maintenance. However, it is important to be aware of potential problems and how to troubleshoot them:

• Leaks: If a leak is detected, it is important to locate the source and repair it promptly to prevent further damage.
• Corrosion: Corrosion can be prevented by using barrier PEX or by wrapping the fittings in a protective sleeve or conduit.
• Freezing: In areas with freezing temperatures, it is important to bury the fittings below the frost line to prevent freezing and bursting.

In a nutshell: The Importance of Proper Burial

By following the guidelines outlined above, you can ensure that your PEX fittings are properly buried underground, providing a reliable and long-lasting plumbing system. Remember, the key to success lies in choosing the right fittings, considering the environmental factors, and adhering to proper installation and maintenance practices.

Frequently Discussed Topics

Q: What type of PEX fittings are best for underground use?
A: Type B PEX, PEX-AL-PEX, and Barrier PEX are all suitable for underground burial.

Q: How deep should PEX fittings be buried?
A: PEX fittings should be buried at least 18 inches below the frost line or the depth required by local building codes.

Q: Do I need to use a protective sleeve or conduit when burying PEX fittings?
A: Yes, it is recommended to wrap the fittings in a protective sleeve or conduit to prevent moisture and soil damage.

Q: Can PEX fittings freeze underground?
A: Yes, PEX fittings can freeze if they are not buried below the frost line.

Q: How do I troubleshoot a leak in an underground PEX fitting?
A: Locate the source of the leak and repair it promptly using a PEX repair clamp or by replacing the damaged fitting.