Outdoor lamp post lighting goes beyond illuminating our home exterior and providing a warm ambience for entertaining guests. It also helps to deter crime. Here is a step by step guide for installing this type of light fixture.
Part 1: Underground Works
Step 1: Rough out a hole about 18 inches deep using a posthole digger. Crosscut a concrete form 2 inches longer than the depth of the hole. Drill a hole near the bottom of the concrete form, then fit the form with a 1/2-inch diameter PVC conduit and a 90-degree elbow. With PVC cement, glue all the pieces together. Put the conduit riser in the form’s center, then tape the elbow on to the form. Covering both ends of the conduit with tape to protect these.
Step 2: Put the form inside the hole then level it. Backfill around the concrete form with soil. You may also use scrap wood braces to hold the form in place.
Step 3: Shovel concrete into the form carefully. See to it that the PVC conduit riser stays centered in the form.
Step 4: Check the foundation for level then with a hand float, smooth the surface of the concrete.
Step 5: Thread anchor bolts into the hold-down bracket. Leave 1 inch of threads at the top then press the bolts into the concrete.
Part 2: Running the Conduit
Step 6: Dig a trench from the outdoor light post up to the power source about 18-inch in depth. Remove the concrete form, then peel off the tape from the conduit stub. With a coupling, glue the first stretch of conduit to the stub. In case you need to make a turn, glue a 45 or 90 degree elbow in place.
Step 7: If you are installing the conduit under a deck, you will need to install a slip coupling and an LB conduit body. Glue the slip coupling to the lower end of the 1/2-inch LB conduit body. Drill a hole through the band joist of the deck about 1-inch in diameter. Glue a length of 1/2-inch conduit to the LB fitting. Drive a screw through the mounting tab of the LB conduit body and into the deck framing. Run the conduit under the deck, supporting every 4 feet with hangers. If you do not have adequate headroom under the deck, you will have to remove the deck boards in order to install the conduit.
Part 3: Electrical Works
Step 8: Tap the GFCI-protected receptacle by shutting off the power to the receptacle. Remove its weather-proof cover then mount a metal extension box over the receptacle.
Step 9: Run a 1/2-inch EMT conduit between the box extension and a tee conduit body. Stretch a length of conduit down from the tee conduit body through the deck. Connect the EMT and the PVC conduit under the deck using a male adapter and a threaded coupling. Bring a second length of conduit up from the tee conduit body for the switch box, then install the switch box. Fasten the fittings.
Step 10: Install separate insulated 14-gauge wires. Make sure to avoid the cable as this is difficult to pull through the 1/2-inch conduit. Pull the white, black and green ground wires from the receptacle and switch box to the light. Leave at least 8 feet of excess wire above the concrete base.
Step 11: Mount the light heads on the post. Feed the wires into the post starting from the bottom up to the top. Join the wire leads from the light heads to the circuit wires. Connect like-colored wires using twist connectors. Tape the wires together with vinyl tape to keep the weight of the dangling circuit wires from straining the connections.
Step 12: Tip the post up, then settle the base over its hold-down bolts. Firmly secure the nuts with a wrench.
Step 13: Place the white and green circuit wires from the light directly into the receptacle box. Pigtail these to the white and green wires from the cable that’s coming from the house, then attach them to the outlet receptacle. The white wire should connect to the receptacle’s silver screw, while the green wire to the green screw. The pigtailed black wire should be connected to the brass screw.
Step 14: Ensure that the electrical assembly is grounded safely. Make sure that the switch has its own ground wire, and the metal conduit and fittings must also be grounded.
Step 15: Mount the weather-proof cover plate over the switch box. The external lever will control the toggle below it.