Romex is a brand name that’s also come to refer to a type of electrical wire. This type of wire is a non-metallic wire housed in a flexible plastic-like material. An electrical conduit is a tube designed to carry, insulate, and protect wires. Conduit may be metallic (like copper or aluminum) or non-metallic (like plastic, rubber, or PVC).
In most cases, you can strip Romex wire and run it through conduit. However, you should also consider local codes before doing it. For example, if the outer sheath has markings to indicate things like the insulation type or temperature ratings, you may need to leave it.
In this article, we’ll explain everything you need to know about using Romex wires, along with some pros and cons. We’ll also discuss running Romex in conduit in more detail, so you know exactly what to expect and how to do it.
Can Stripped Romex Wire Run Through Conduit?
Technically, stripped Romex wire can typically be run through a conduit. However, the work may not be up to code or pass an inspection. So, while it may be an easier fix than calling a professional, it could end up costing you more time and trouble in the long run.
For example, the individual wires inside the Romex cable aren’t individually labeled. So, removing the outer jacket and running multiple unmarked wires through a conduit would not be up to code.
But if you’re not concerned about codes or inspections, you may be able to do this task without any issues. Just be sure to use the appropriate conduit type for the environment.
Advantages of Using Romex Wires
There are many advantages to using Romex wires, which is why they’re so popular in residential settings. For one, they’re easy to use and handle, and you don’t have to worry about conduits since they’re already insulated.
1. Available in Various Sizes
Romex wire is available in three different sizes. Depending on your project, you can easily find the right size wire already bundled in an insulated coating and ready to use. Here are the wire sizes available:
- 14-gauge: Has a white outer sheath and is most commonly used for 15-amp circuits. Small household appliances like lamps and fans are most suitable for this Romex wire.
- 12-gauge: Has a yellow outer sheath and is most commonly used for 20-amp circuits up to 2,500 Watts.
- 10-gauge: Has an orange outer sheath and is most commonly used for 30-amp circuits up to 7,200 Watts. Examples are larger appliances like microwaves and space heaters.
2. Suitable for Home and Office Use
Romex wire is perfect for at-home DIY projects and electrical work. It’s safe and easy to use, so it’s suitable for both residential and commercial settings.
If you need to run a wire to power a fan or lamp, Romex wire is perfect for the job. You can hide it behind a wall without having to use an additional conduit, making it more user-friendly than other conductors. Romex wires are easy to cut and smooth for sliding them through holes.
3. Comes in Color Codes
Romex wires are color-coded, making it easy to determine which one you need. Each color indicates the wire’s size. Color coding based on size means you can quickly and easily identify and pull the size wire you need for the job.
Here are the most common jacket colors and wire sizes:
Yellow – 12-gauge, rated for 20 Amps
White/Grey – 14-gauge, rated for 15 Amps
Orange – 10-gauge
Black – may be 6-gauge or 8-gauge
Note: Gray is typically reserved for underground (UF) cables or service entrance cables (SE/SER).
So, instead of trying to guess which size wire you need or having to eyeball whether the cable will fit into the opening, you can quickly determine at a glance which wire you need for the project. Color coding saves time and reduces rework.
Disadvantages of Using Romex Wires
Even though there are plenty of “pros” of using Romex wires, there are also some disadvantages to think about as well. Before making your decision about which materials are best for your project, here are some of the downsides to consider.
1. Not Suitable for Outdoor Use
Despite its durable coating, Romex wires are not suitable for outdoor projects. In some situations (like in a shed or garage), a Romex wire may do just fine, but if the cables are exposed to the environment or buried, you’ll need to use NEC-specified wires for outdoor use.
If Romex wires are exposed to damp environments, the moisture can penetrate the jacket and cause problems with the copper ground wire. Unlike some other cables, the ground wire in a Romex isn’t fully coated, leaving it vulnerable to moisture, temperature, and other environmental conditions.
Wires used in outdoor conditions have specific requirements for conduit and proper insulation that Romex wires don’t meet.
2. Sensitive Entry and Exit Points
Romex wires are known for being susceptible to damage at the entry and exit points. That means if you’re not careful, you can damage the wires while you’re installing them. To prevent any accidental damage, it’s important to use the right kinds of connectors or brushings to protect the ends.
Using Romex wires is sometimes more expensive than using other types of wiring, so you’ll want to avoid any unnecessary damage that might increase the cost even more. Plus, you don’t want to have to pull the cabling out and start over because you damaged the wiring.
3. Requires a Specific Conduit
Using conduit with Romex wires means you’ll need to be sure to select the right size conduit to fit the cabling. Remember, Romex is comprised of multiple wires encased in a protective jacket. So you’ll need to choose a conduit that’s big enough to fit the wires and the coating.
If you try to use a conduit that’s too small, the Romex wire may not fit inside, or you may damage the wire or jacket. Plus, these types of wires can sometimes generate heat, so you’ll need to have enough space inside the conduit without it being overcrowded.
Why Should I Run Romex in Conduit?
There’s some debate over whether you can or should run Romex wire in conduit. After all, the wire is already coated in a protective jacket, so you may feel like you don’t need an additional conduit. However, there are some benefits to using conduit you should consider.
1. Protection
Using conduit with your Romex wires will add even more protection than you’ll get with the insulation jacket alone. All wires are susceptible to damage or other impacts from their environments, so using a conduit helps reduce the potential for a tripped breaker or short circuit.
Romex wiring isn’t designed to use in wet locations or outdoors, so using a conduit will help protect the Romex from moisture in the air. It also helps to protect the cabling from heat and temperature changes. Pressure and gasses can also impact wiring, so conduit can help eliminate those issues, too.
Finally, wires are less likely to get chewed up by unwelcome critters when it’s run through a conduit. To keep squirrels and rodents away from your Romex, use a conduit to add even more protection.
2. Weather-Resistant
Since Romex can’t be used outdoors or in wet environments, using a conduit will protect the Romex from harsh weather. Even if you use it on a wall or in a ceiling, there’s still a chance that the weather can impact the wiring.
A conduit will save your Romex from getting damaged and needing to be replaced due to weather concerns, which can save you a lot of time and money in the long run.
3. Durability of Wire
Romex wires are known for being durable, but they’re still susceptible to damage from the elements. A rogue squirrel or rodent could decide to gnaw on your Romex coating, causing damage to the wires inside.
Using a conduit helps increase the wire’s durability tremendously. It means your wiring will last longer and be able to stand up to the conditions impacting it.
How to Run Romex Wire in Conduit
To run Romex wire through a conduit, you will need:
- Romex wire
- Conduit
- Wire stripper
If you choose, you can feed the Romex through the conduit without stripping it first. But you should know that you’ll need to check your local codes first to ensure it’s allowed.
Otherwise, simply strip the wires of the protective jacket and feed them through the conduit of your choosing. Just make sure there’s enough room in the conduit for the appropriate wire fill limit.
Ruben has a diverse background in the home services industry, with experience running a construction company, a kitchen and bath showroom, and a moving and relocation company. This breadth of experience has provided him with a wealth of knowledge and expertise in various areas of home improvement in general and specifically in the heating and plumbing niche.