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You will need to run wires through your exterior walls every once in a while. It’s a great way to add wiring to the garage or workshop. You can quickly run these wires through a conduit.
You can find conduits that are resistant to impact, moisture, and vapors. They are outdoor weather resistant. Conduits can be made submersible or waterproof.
By knowing how to run conduit through an exterior wall, there won’t be exposed wires running along walls to ruin the exterior of the house.
How to run a conduit through an exterior wall
First, you’ll drill a hole in the wall using a drill bit. The size you choose will be a bit larger than the size of the conduit.
Then, cut and bend the conduit as required (more details below).
Next, slide the conduit through the hole in the wall. Add conduit supports where needed.
Finally, use caulk to seal the gaps in the wall.
Choosing the Conduit
PVC conduits are best for putting underground because they are corrosion resistant.
– PVC Conduit and connector kit
They often come in a gray color so that people can differentiate between an electric line and a water line.
There are metal conduits that will shield circuits from electromagnetic interference.
If you need to pull 3 or 4 wires, you will need a PVC conduit that is at least 1/2 inch. You might need to add wires in the future. So, it’s a good idea to use a larger one.
You will need to mark the area you want to use the conduit. After marking, measure the length of the EMT or PVC conduit that you will need.
Below is a step by step guide to install a conduit through your exterior wall.
How to Run Conduit through Exterior Wall – 6 Steps with Bonus Tips
Step 1: Drill a hole in the wall
First, drill a hole in the wall. You will need to choose the right size of the drill bit. The hole size should be able to hold the conduit.
– Spade drill bit – Check Price >
Step 2: Cut and bend the conduit
For EMT conduit and non-flexible conduit, you will need to bend it with a bender. Without a bender, you can use fittings with 90- and 45-degree angles that will connect the straight sections of the conduit.
For 90-degree bends, an easy solution is to use a pulling ell. It has a removable cover that you will use to bend the wires around the corner.
– Pulling ell or L fitting – Check Price >
For PVC conduit, you can use a propane torch to heat the pipe to bend it to the angle that you need. It will hold the shape once it is cooled.
After taking the measurement, measure the conduit, and cut it accordingly.
For thick metal conduit, a circular saw will make the cut smoother.
– Circular saw – Check Price >
Conduits need smooth insides with no sharp edges for easy pull through action that won’t ruin conductors.
So, use the blade of a screwdriver to smooth-out the inside edge of the cut end.
Next, use slip-joint pliers on the outside of the cut end to remove any sharp edges.
Step 3: Slide the conduit through the hole
Now you will slide the conduit through the hole in the wall.
You likely need an ell puller. The ‘L’ or “el” stands for the 90-degree bend. The second letter refers to the direction of the exit point.
– LB – “Back” conduit fitting – Check Price >
– LL – “Left” conduit fitting – Check Price >
– LR – “Right” conduit fitting – Check Price >
Check that there is enough space for the conduit in the drilled hole of the outside wall.
Before sliding the conduit through the wall, make sure that there is no presence of water. Remember to add a GFCI breaker if the wires will be near water.
The L fitting will help you turn the wires around at a 90-degree angle, inside the conduit. The back part of the L fitting will be removable so that you can pull wires in or out easily.
Attach the conduit with its L fitting. If working with PVC, you can use PVC glue.
You may use a conduit connector for solid attachment to the wall and ground connection. Be sure to really tighten the nuts onto the box connector.
If you’re using an existing electrical box to run the conduit, you will need a box extension. For a single gang box, use a 4-inch square box.
– Box extension for threaded outlets – Check Price >
Use an offset fitting for where the conduit enters the box.
– Offset fitting – Check Price >
Step 4: Add conduit supports
For conduit running along the wall, you will need to support it with conduit hangers.
– Conduit hangers – Check Price >
Measure 3ft from the box for the first hanger.
Then, the next hangers will be 10ft apart.
Measure and mark where the hangers will be.
Conduit hangers can be attached with a screw.
You will need drywall anchors for areas that do not have a solid attachment.
– drywall anchors – Check Price >
Step 5: Pull the wire through the conduit
You can use fish tape to pull the wire all the way through the conduit.
– Fish tape – Check Price >
The removable lid of the L fitting will help you turn the wire around the corner.
Now the conduit, its connectors, and wires are slipped through the hole in the wall.
Step 6: Seal wall gaps with caulk
Finally, use silicone caulk to seal around the connection between the hole in the exterior wall and the conduit.
– Weatherproof silicone caulk – Check Price >
Step 7 (optional): Dig a trench
If you are putting a wire underground, you’ll have to dig a trench.
You should contact your local municipality before digging the hole. They will inform you of existing lines (electric, water, gas, etc) where you want to dig.
Use a shovel to dig a narrow hole about 25 inches deep.
For longer wire, use a trenching machine. These are also available for rent at local hardware stores.
– Electric lawn trencher – Check Price >
Filling the trench
After you run the wire through the trench, put a layer of sand in first. This layer acts as a warning for any future diggers.
Then add red caution tape over the layer of sand.
– Caution warning tape – Check Price >
Finally, add the soil as the top layer.
How to Install EMT Conduit?
EMT conduit is commonly used to install electrical conductors in houses.
You will need to mark the area you want to cover with the conduit. After marking, measure the length of the conduit that you will need.
Use a hacksaw to cut the conduit. If the cut has not been smooth, use a tool to smooth out the corners, such as the blade of a screwdriver and pliers.
Use a fishing tape to pull the wires through the conduit.
– Fish tape – Check Price >
Do Electrical Wires Need to Be in Conduit?
Yes, electrical wires need to be in conduit for protection from outside forces like sunlight, rain, chemical vapors, crushing force, etc.
Based on your needs, you can use any type of conduit made from plastic, metal, or fiberglass. You can choose rigid ones or flexible ones.
It is a good idea to conduit electrical wires. As electrical wires can be very sensitive, you will need to protect them.
Also, conduits like PVC conduit or electrical metallic tubing (EMT) conduit will last for a long time.
The wires that are kept in the conduit stay in a more organized way. If you need to repair or work with the wires, you will easily find all the wires.
Finally, make sure the conduit is grounded with a wire that is securely connected to the ground.
With the right tools and techniques, you can run a conduit through your exterior wall successfully.