Installing PVC Conduit

If you are looking to run electricity to the outdoors you will be tapping into an existing circuit from inside the house and running conduit with wires outside. The new trend these days is to have a great outdoor living space and one way to spruce up your deck or patio is to have TV, speakers or any other electrical device outside. Cable runs from the breaker box to a junction box inside the house. Inside the junction box, each wire in the cable is attached to a corresponding cable or wire. A nipple is a length of conduit that protects the cable as it runs through the wall. Outside, attach the nipple to an L-shaped fitting called an LB fitting. This fitting has a removable plate that turn the cable toward the ground. The fitting mounts onto conduit that goes down the house wall and into an 18 inch deep trench. From there, an elbow fitting allows the conduit and cable to run along the bottom of the trench, and to the desired location in the outdoor living space. It sounds a little complicated but it's not, here's how you do it.

Using a hammer drill and percussion bit, drill a hole through the house wall just above the foundation where you want the wire to enter the house. This hole should be wide enough to accommodate an LB fitting and a nipple. Cut a PVC nipple to length so it extends 1 inch into the inside. Install it through the hole and glue the LB fitting on the end of the nipple that extends outside. Push the assembly into the hole until the fitting is against the wall of the house.

To accommodate the conduit and the wire you must dig a trench starting directly under the LB fitting. Make the trench about the width of a shovel and about 18 inches deep as code requires this depth for PVC conduit. You might want to check your local code to be sure but I'm quite certain that this is code everywhere. Next, attach a piece of conduit to the LB fitting. With a small paintbrush, spread PVC adhesive onto the conduit and push it into the opening at the bottom of the fitting. Leave space to fit an elbow at the bottom of the conduit. Next cut and assemble the entire run of conduit in the trench. Go back and spread PVC adhesive on an elbow and glue it to the conduit running down the side of the house. Glue the remaining length of conduit together.

Once you have laid and glued all the conduit together you need to attach the conduit to the house wall with plastic straps. Drill holes in the foundation for shields, then insert the shields in the holes. Screw into the shields to hold the straps in place. A shield is basically a concrete anchors that hold the screws into place so you don't have to worry about the concrete cracking or the screws falling out. Finally, you need to caulk the gaps between the siding and the conduit to create a watertight seal.

You will most likely be cutting the conduit so you can get it to where it's supposed to go. Cutting PVC conduit can be a little tricky and frustrating. The best way to cut it is by placing the conduit into a vice and cut using a hacksaw. A hacksaw with a 32 teeth per inch blade works really well for PVC. Cutting PVC usually results in those little burrs, remove them with a utility knife and if you are really particular you can use a little sand paper to smooth them out. You also will need to bevel the outside edges so it will fit the couplings. You really want to be sure your cuts are clean and your connections are secure.

This is a pretty easy project, it takes some time and patience but it really is pretty easy. The best thing to have is a plan before you begin. With this project you really don't want to be winging is as you go. It will be much easier and faster if you know exactly where you are going and how you are going to get there. Good luck.