Below Ground Wiring Installation

Below Ground Wiring Burial Depth
1. The following table lists how much cover is required for wiring and conduit buried underground. Depths are in inches.

Protection where Wires Emerge from Ground
1. Protect wires where they emerge from the ground using enclosures or raceways beginning at the wire’s minimum burial depth or at least (≥) 18 inches below where the wires emerge from the ground, whichever is less. Extend the protection to at least (≥) 8 feet above fi nished grade.
2. Protect wires at the point where they enter the building.

Below Ground Splices and Taps
1. You may splice or tap below ground wires using approved methods and materials. Boxes are not required when using methods and materials approved for splicing and tapping buried wires.

Raceway Seals
1. Seal conduit and tubing at both ends where moisture could enter and damage wires.

Conduit Installed Below Ground
1. Treat conduit installed below ground as a wet location. Do not use wiring methods that are not approved for wet locations, such as NM cable, in buried conduit.
2. Protect metal conduit and tubing installed at or below ground from corrosion by tape, coatings or other appropriate means.
3. Install cables listed for burial in conduit listed for burial when run under a building. You may use MC cable if the cable is listed and labeled for burial or concrete encasement. Refer to the IRC for additional restrictions on using MC cable under a building.