About Romex®NM-B Cable
We sell the South Wire brand Romex ® wire and UFB Cable. It’s used for indoor and outdoor electrical wiring applications. Romex® is for indoor use only and the UFB cables can go outdoors and even directly underground without conduit. They come in 2 and 3 conductor in AWG sizes 14, 12, and 10.
We also sell the larger cables in the 8, 6, 4, and 2 AWG by the foot. We understand that you have exact lengths and want to limit waste, so we allow you to purchase any length at all on the larger Romex ® wire and UFB Cables.
If you’re looking for just the THHN wire inside the cable please see our electrical wire. We also have hook up wire for indoor use on appliances and Welding Cable for flexible outdoor use.
Things Know About Romex® NMB Wire
Romex® NMB by Southwire is a thoroughly insulated electrical wire developed in 1922. It was originally owned by the Romex® Wire Company, which was later on purchased by General Cable in 1927, and purchased by Southwire in 2001. Romex® wire is often used in home and small business wiring applications.
Before its Southwire acquisition, Romex® was originally wrapped with braided cotton. It was modified later on and provided with PVC covering and non-metallic nature. The non-metallic nature of Romex® NMB by Southwire proved to be a disadvantage though as it became very sensitive to heat, water and physical damage. Because of this, Romex® NMB by Southwire became limited — it cannot be used in areas where heat, agitation, water and even dampness is present.
This however did not make Romex® altogether inefficient. It was, later on, discovered that this type of wire is very useful outdoors and inside the house when provided with sufficient covering. They became useful for interior walls, garages and above ground surface wiring applications. However, there are careful measures that you have to do first to ensure that you can safely install Romex® wires outdoors. There are also specifications that you have to remember so that you will not violate National Electric Code regulations.
Your first priority must be prevention of damage to the Romex’s® sheathed cables or any point where it will enter or leave. You must make sure that these points are fitted by the appropriate connectors or brushings at all times. Look for connectors and brushings that are specifically manufactured for Romex® conduits.
You must also be careful not to place your Romex® wire in conduits which are too small for the cable size. Doing this may damage, bind or crush the sheathing. Make sure you always select a conduit size that will allow your Romex® cable to pass through easily.
Take note of your local jurisdiction code. The NEC codes usually vary from state to state. Look for your local code enforcement building department so you can ask for guidance whenever you plan on installing Romex® wires. They will send a building inspector as well as a very experienced technician to check if your wiring project can be approved.
Try to place your Romex® wires in PVC pipes before using them. Make sure the wires are not buried more than 3 to 4 inches from the ground’s surface. If you can, just run the wires along building boulders — you can, later on, clip them in place so that they won’t slip or be exposed to element exposure.
If you can, hire a very good technician who can help you obtain stable electrical conditions especially when the wires are installed outdoors. Make sure you replace your Romex® wires after a year or two. Always have your wires inspected so that they will still conform to NEC standards during use.
Romex® wires are indeed very useful. However, always bear in mind that it has a very sensitive nature. Making sure you comply first with the NEC codes before you set a wiring project in motion can save you lots of trouble.
UF-B Cable can be used outdoors and underground if you need more protection. We also offer many types of portable power cable that have a rubbder insulation and jacket for added flexibility and protection outdoors.
Please call us with any specific requirements. We also offer FREE SHIPPING over $250.00 and stock this material in many different areas throughout the USA. Call now (800) 334-8400!
NMB Cable Acronym
NMB cable sands for Non-Metallic Sheathed cable. It’s specified as non-metallic because it has a PVC jacket and it’s used indoors only. Metallic Cable, or MC cable, uses an aluminum interlocked armor for a jacket because it also works as a conduit for indoor applications. NMB cable would need to be installed in duct or conduit if it were being used in the same application as MC cable.
Romex® NMB Cable
Romex® is a brand name of NMB cable created by Southwire. Southwire also branded the name SIMpull® because its special jacket is easy to pull through conduit. Southwire has been designing and manufacturing electrical cables for years and they’re known as a reputable supplier of USA made products in the industry.
You can buy NMB cable from any number of manufacturers that also design a great cable. It’s manufactured with copper strands, Thermoplastic insulation and a PVC jacket. It’s manufactured in a cost-effective way for the most basic of applications. That doesn’t mean the copper is drawn in China, it’s 100% manufactured in the USA. I’m talking about the protection from the jacket and insulation only being sufficient enough for indoor applications. Environmental conditions will tear the insulation apart long before it’s expected life.
Romex® Wire Information
Romex® wire is a type of electrical wire that was made for an easier installation. It is made up of 2 or 3 conductors of THHN wire with a thin PVC jacket over them so that electrical contractors can run 3 wires through a house at once. Otherwise, they would just use the THHN wires individually.
Romex® wire comes in different sizes depending on how much power needs to be run. The Romex® 14/2 and 14/3 have a white jacket, the Romex® 12/2 and 12/3 have a yellow jacket and the Romex® 10/2 and 10/3 come in the orange jacket. The color only represents the AWG size of the wires inside the jacket so that an electrician knows what size it is by looking at it. You should always speak to an electrician before trying to pick an AWG size yourself because there are many different factors to think about first. They will ask you the proper questions to get the information that they need and then run the calculation for the right AWG size. You can ask your electrician about any type of electrical wire and they’ll be glad to help.
We get a lot of phone calls where people ask if the wire we sell is real copper. All wire made in the USA must be made to certain standards and they have to be approved. As long as the wire is made domestically then you can be assured you’re getting the right product. We buy all of our wire and cable from the largest most reliable manufactures in the industry. It takes a long time to buy wire and cable from places like South Wire or General Cable because they require large stocking orders and year-end minimums. If you don’t meet the requirements then they don’t have to sell to you. Not only does that mean we sell a good quality product but also that we have the cheapest price.
If your product says Romex® on it then that means South Wire made it because it’s a brand name that South Wire owns. So that also means you’re getting a product that came from the best in the business.
Romex® cables are used in homes and buildings to hook up power from the electrical panel to the lights and appliances throughout a particular home or building. The most popular AWG sizes are the 14 AWG, 12 AWG and 10 AWG so they are each specified with their own color. Romex® 14/2 and 14/3 come in a grey outer jacket, Romex® 12/2 and 12/3 come in a yellow jacket and Romex® 10/2 and 10/3 come in the orange outer jacket.
The reason for the color codes are because it makes it much easier for an electrical contractor to tell the difference of each cable just by looking at them. They also get phone calls from people in their homes about replacing a wire that may have been cut or ripped somehow. So the easiest thing for them to ask is, What color is the wire? That way they can bring the correct Romex® wire with them to the job. There are many different types of electrical wire so it makes it much easier for the contractor to bring the correct items with them.
Anything bigger than the 10 awg Romex® comes in a white outer jacket. That’s standard and you can’t even request another color unless you want to buy a full minimum run of Romex ®. If you wanted a minimum run we could get that done for you with a 4-6 week lead time and a 50,000 foot run of wire. Otherwise, Romex® 6/3 and Romex® 8/2 all come in the same outer jacket color.
UFB cable comes in gray only. It’s an underground cable anyways so having a specific color would be just about pointless. You can run UFB through conduit if you would like but you definitely don’t need to. It was built tough for the rough outdoor weather so it will be able to handle just about anything that comes its way. UFB cable has the same inner wires as the Romex ® cable does. The both have THHN / THWN conductors with a pvc insulation and a nylon coating. You can also buy the THHN wire by itself if you need and run the wires individually. It may take a bit more time but you will save some money in the long run.
Romex® electrical cable is a multi-conductor THHN cable that has an optional ground wire. Romex® NMB is made with a thin PVC jacket manufactured as an indoor-only cable which also excludes it from conduit use. This is a common question in the electrical field because Romex® is very popular and sometimes a run needs to go outdoors for a few feet and the Romex ® specifications do not permit any outdoor use.
The next step up for an outdoor cable is Type MC cable which is also made with THHN wires and an additional green THHN wire as a ground. Having a THHN ground wire means the cale can be used outdoors or in conduit because there’s no change of moisture hitting the bare copper. “MC” stands for Metal Clad because the jacket is an aluminum metal clad jacket which is great for pushing MC cable through conduit.
UFB cable is similar to Romex® as well because it’s also made with THHN wires and a bare copper ground wire. However, with UFB, the ground wire and the THHN wires are individually covered by the extra protection of the UFB jacket. UFB is also known as an underground cable because it can be buried directly in the earth to hook up a new electrical panel in your barn or garage.
You can call us for help finding the exact electrical wire you need whether it’s portable cord, welding cable or any type of electrical cable.
All Romex®, or NMB cables, must stay indoors. They cannot run outdoors at all because they don’t have enough protection to withstand outdoor conditions. You can pay slightly more for a UFB 14/2 cable that runs indoors, outdoors and directly underground without conduit. Each conductor is covered individually by the thick durable PVC jacket.
We ONLY sell the best quality Southwire SimPull Romex® brand so that our customers can make their money last as long as possible.