Minimum Burial Depth
Fast reference for common residential and commercial trench depths and cover rules.
Related NEC Tables
Professional Usage Disclaimer
This data is provided for informational purposes only. Always verify with the latest edition of the National Electrical Code (NFPA 70) and consult with a licensed electrical professional or AHJ (Authority Having Jurisdiction) before performing any electrical work. Zing² is a reference tool, not a substitute for qualified engineering.
Professional Field Notes & Gotchas
- ▸'Cover' vs 'Depth': NEC measures 'Cover' from the top of the conduit/cable to the finished grade. Trench depth must account for the diameter of the pipe plus the required cover.
- ▸Residential Driveways: Requirements for 18 inches of cover apply to one- and two-family dwelling driveways. Public streets always require 24 inches regardless of wiring method.
- ▸GFCI Protection: 120V circuits protected by a GFCI before entering the ground can often be buried at shallower depths (12 inches for direct burial) per Column 4.
- ▸Under Slabs: Wiring under a building is considered 0 inches of cover as long as it is in a raceway and extends beyond the building footprint per 300.5(C).
NEC 2023 vs 2026: What changed?
NEC 2023 vs 2026: New notes were added regarding 'Finished Grade' to prevent disputes when landscaping or pavestones are added after inspection. The core depth values remain unchanged from the 2023 cycle.
Technical FAQs
How deep to bury PVC conduit in a yard?
For most general non-driveway areas, PVC conduit (nonmetallic raceway) requires a minimum of 18 inches of cover per NEC Table 300.5.
What is the burial depth for 12/2 UF cable?
Direct burial UF cable requires 24 inches of cover under general areas. If the circuit is GFCI protected and 120V/20A or less, this can be reduced to 12 inches.
Can I bury RMC only 6 inches deep?
Yes. Rigid Metal Conduit (RMC) is robust and only requires 6 inches of cover in almost all locations, making it ideal for rocky soil or areas where deep trenching is impossible.