National Electrical Code (NEC) Rules for Outdoor Wiring Type UF cable is the most commonly used nonmetallic cable for residential outdoor wiring runs. UF cable can be direct-buried (without conduit) with a minimum of 24 inches of earth cover. Wiring buried inside rigid metal (RMC) or intermediate metal (IMC) conduit must have at least 6 inches of earth cover; wiring in PVC conduit must have at least 18 inches of cover. How to Wire Your Outdoor Water Fountain | DoItYourself Wiring your outdoor water fountain was a challenge, but you tackled it fearlessly. Now, you are finished and can enjoy the fruits of your labor without any safety concerns. More From Doityourself Related Posts. GFCI problem I replaced the regular outlet on my porch with a