Revised: September 27, 2020 @ 4:30 PM.

Background Information

This is an existing installation by a national builder. I had to dig up this section for another reason and found a PEX splice. I wanted to determine if I need to do something to better protect the PEX pipe before covering this backup.

Side Rant: It may have been installed by code, inspected and approved, but code is a minimum standard. Sometimes minimum standard is fine. Sometimes, the inspector misses it or the installation is altered after inspection.

I may decide to buy the tools or decide to hire a plumber (if I can find one) with the correct tools to fix any problems before I re-bury the line. Let me be the judge of what is too expensive.


  1. Does PEX pipe that is buried in the ground need to be protected? If so, how?

  2. Does PEX pipe fittings / splices buried in the ground need to be protected? If so, how?

  3. How should the PEX pipe be protected as it is going through the PVC sleeve penetrating the footing/foundation? It appears that the PVC could cause chafing of the PEX over time via expansion / contraction process.

  4. The writing on the PEX says, "Pure Flow". Is that PEX-B?

Picture of dig site

PEX Splice

The PEX Splice appears to be a plastic fitting with copper crimp rings.

Picture of PEX Splice

Pureflow PEX Writing

Note: I noticed that as I was cleaning the pipe, the writing was coming off the PEX Pipe. The dirt was acting as sandpaper. So I have be very careful as I was cleaning the dirt away from the PEX so that I could get a good picture of the writing on the PEX.

Picture of PEX writing

PureFlow Water Systems Installation Manual - June 2009

Source: https://www.houseneeds.com/upload/pdf/viega-pexsystemmanual.pdf ` I did a search and found "PureFlow Water Systems Installation Manual".

When direct burying PureFlow fittings, PEX Press fittings do not need to be wrapped; however, Brass PEX Crimp fittings do. When Brass PEX Crimp fittings are put in contact with ground soil by direct burial, it is the position of Viega, that these brass fittings and copper crimp rings be securely wrapped using self-fusing, fully cured silicone rubberlike tape with a minimum 0.020" thickness.

Contact a Viega representative for additional information on approved wrapping materials.

Viega PEX Water Systems Installation Manual -

Source: https://www.pexuniverse.com/uploads/literature/viega-pex-installation-manual.pdf

Viega PEX Crimp fittings (Eco Brass and Polymer) and their crimp rings shall be securely wrapped with tape meeting the following criteria for direct burial installations.

  • Self-fusing
  • Formaldehyde-free
  • Fully cured silicone tape
  • Minimum of 0.020" thickness

The wrap is available from Viega (part number 15320).

** Repair coupling tape (PN: 15320) **

Viega Website: https://www.viega.us/en/products/Catalog/Heating-and-Cooling-Systems/Heating-and-Cooling-Solutions/Couplings/Repair-coupling-tape-2890-4US.html

** Product Instructions - Viega PureFlow Coupling Repair Wrap **

Vendor instructions to using the "Coupling Repair Wrap": https://www.viega.us/content/dam/viega/aem_online_assets/download_assets/us/pihc_560939_1119_coupling_repair_wrap_enesfr.pdf

Note: Viega Wrap appears to be similar to the SharkBite Wrap idea provided in the "jwh20"'s answer below.


SharkBite - Non-Adhesive Multi-Purpose Silicone Wrap

  • HomeDepot: $13.98

Viega - Repair Coupling Tape for PEX Press Fittings (PN: 15320)

  • SupplyHouse.com: $22.39 - Out of Stock

Viega - 10 foot Coupling Silicone Tape (PN: 15320)

  • Ferguson: $29.09 - Out of Stock in my area
  • 3
    But why? Regular (non-crosslinked) black (or blue if you want this fancy price) polyethylene well pipe is far more durable and "made for this purpose." Even there, if going under a driveway, sleeving it in PVC pipe so you can dig up both ends and pull the PEX or Poly out without digging up the driveway is cheap insurance.
    – Ecnerwal
    Sep 22, 2020 at 14:24
  • Ecnerwal, thank you. This is an existing installation by a national builder when the house was built in 2014. Sep 22, 2020 at 15:01
  • 1
    Ah, yes - where "national builder" can be interpreted as "cuts every corner possible" - got it - cheapness rules.
    – Ecnerwal
    Sep 22, 2020 at 15:04
  • I don't think there's anything wrong with the existing installation as you described it. A conduit under the driveway would've been better, and no splice would be better; but what you've described meets major manufacturer' guidance and probably complies with your local building codes. As a regular homeowner myself, I, too, have been surprised to learn what's able to be just buried in the ground! Sep 22, 2020 at 16:39
  • I figured that since it was already dug up, I could do something to increase the life of the installation. I believe it is a Brass PEX Connector with copper rings. I am going into my retirement years and need to keep expenses low during retirement. Just did not save enough. Sep 22, 2020 at 20:14

1 Answer 1


Yes, but be sure to bury it below the frost line and ensure that none of the backfill is large enough to puncture or damage the pipe. A clean run of PEX is preferred but if you must use joints, follow the procedure from the manufacturer.

In the case of Sharkbite connectors, the manufacturer does support using them buried provided you follow their procedure:

Buried Sharkbite Connectors

I'll note that some prefer PEX crimp connectors for this application but if you don't have the tooling that can be cost prohibitive.

  • 2
    Pex can be joined with shark bite connectors but it is not the 1st choice. Pex crimp connectors are the preferred method of joining
    – Kris
    Sep 22, 2020 at 13:32
  • @Kris I updated my answer to reflect that. Thanks!
    – jwh20
    Sep 22, 2020 at 14:01
  • Tooling is not a problem. I will hire a plumber to correct any problems with the install. This is an existing installation by a national builder in 2014. I had to dig up this section for other reason and discovered the PEX. I'll explain more later. Sep 22, 2020 at 15:03
  • jwh20, what PEX Crimp connectors and tools do you use? Sep 27, 2020 at 21:29

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