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Your distribution source for Belden Cable, Alpha Wire, Southwire Cable and equals
Your distribution source for Belden Cable, Alpha Wire, Southwire Cable and equals

THHN vs Romex Cables

When it comes to electrical wiring, there are a lot of options. But when you need something for general purpose wiring, two of the most popular choices are THHN vs Romex cable. 

In this blog post, we'll discuss the differences between these two types of cable and which one is best for different applications. THHN is a great choice for conduit or wiring embedded in walls or ceilings since it has a high-temperature rating and excellent protection against moisture and abrasion damage.

In contrast, Romex is a great choice for more cost-effective wiring in residential projects like lighting circuits or outlets. It’s easier to install with no specialized tools required, too.

But whether you need Romex wires or THHN wires, AudioVideoElectric.com is your trusted supplier. We offer the same quality as the brand name at a fraction of the price. Shop today or get in touch for one-on-one assistance choosing between THHN wire vs Romex cables!

What is THHN Wire?

THHN stands for Thermoplastic High Heat-Resistant Nylon Coated. It is a single conductor wire that is commonly used in indoor applications such as conduit or wiring in walls or ceilings. It is rated at 600 volts and is made from copper strands coated with nylon insulation. 

THHN cable has a higher temperature rating than other types of cable, making it suitable for high-heat applications such as lighting fixtures or electric motors. The insulation on THHN also provides better protection against moisture, corrosion, and abrasion than other types of wires.

What is Romex Wire?

Romex cable is another type of electrical wire that is commonly used in residential applications such as lighting circuits and outlets. It consists of two or more insulated conductors surrounded by an outer jacket (the “sheath”). 

Romex cable is made from copper strands coated with polyvinyl chloride (PVC) insulation, which provides protection against moisture, chemicals, abrasion, and impact damage. 

Unlike THHN cable, Romex does not have a high-temperature rating so it should not be used in high-heat applications such as lighting fixtures or electric motors. 

Additionally, Romex cannot be installed outdoors unless it is specifically designed for outdoor use as the PVC insulation will degrade over time when exposed to UV light or extreme temperatures. 

THHN vs Romex Cables: Key Differences to Consider

You might already see which is right for you between THHN wire vs Romex cables just from what we’ve covered so far. But since this is such a nuanced decision that you want to get right, we’re going to compare and contrast the two wires side by side below to leave you with a clear grasp.

Applications and Use Cases

The decision between THHN vs Romex wires is actually fairly simple when you know exactly what you intend to use the cables for. They are best suited to different applications.

For example, THHN is ideal for commercial and industrial environments - like inside conduits or raceways for wiring walls, ceilings, or other high-temperature applications. You’ll find them in lighting fixtures, motors, and HVAC systems due to their high-heat resistance and durability.

Meanwhile, Romex wires are primarily designed for residential settings. They’re used mostly in lighting circuits, outlets, and basic electrical installations. Think low-heat, non-conduit environments. 

Cost Comparison

Your budget may dictate which cables use in your project to some degree, too. 

Generally, THHN wire is more cost-effective per foot because it’s sold as single conductors without an outer sheath. Just be aware that sourcing conduit during installation can increase overall project costs. This can sneak up on you if you aren’t prepared for it.

Romex appears more expensive per foot, but it doesn’t need any additional conduit or raceways due to its bundled design (multiple conductors within a single sheath). This reduces overall costs and makes it the more economical choice for simpler installations.

Specifications and Ratings

Even the specifications and ratings for THHN wire vs Romex cables vary. While they’re both rated for up to 600 volts, that’s where the similarities end. 

THHN wires can withstand up to 90°C (194°F) in dry conditions and 75°C (167°F) in wet conditions, whereas Romex is only rated to 60°C (140°F) under typical use.

From a protection perspective, you’ll see that THHN is far more resilient thanks to its nylon coating that shields against moisture, abrasion, and chemicals. Romex wires only have a PVC sheathing, which offers basic protection, but falls far short of THHN wires.

Installation Requirements

The work required to install either a Romex vs THHN wire will differ as well, with THHN being far more complicated. They must be installed within conduits or raceways for protection, which can be quite a labor-intensive task. However, this unlocks greater flexibility in complex wiring setups.

In contrast, Romex cables come with an integrated sheath that eliminates the need for conduit in most installations. It’s easier to handle and install, especially in straightforward residential projects.

So, Which Wire is Right For You - Romex vs THHN?

You likely have a clear understanding of which is the optimal wiring choice between THHN wire vs Romex at this point. Choose THHN for high-temperature, industrial, or commercial environments where durability and conduit installation are priorities.

On the other hand, Romex will get the job done in simple residential projects where ease of installation and cost savings are key.

These are just two of the many types of cables you have at your disposal, though. Learn more about fiber optic vs coaxial cable, coax vs cat5, LSZH vs plenum, solid vs stranded wire, or single conductor vs multi-conductor cable in our blog.

Otherwise, the only thing left to do now that you know which is right for you between THHN vs Romex is source yours from a company you can trust. Look no further than AudioVideoElectric.com.

Whether You Need Romex vs THHN or Anything in Between, Trust AudioVideoElectric.com!

We specialize in providing high-quality, affordable alternatives to brand-name cables like THHN and Romex. Discover options that meet or exceed industry standards for optimal performance without stretching your budget.

From mil-spec cables to multi-conductor cables, bulk coaxial cable, we can help customers save as much as 40-65% annually without compromising on quality. How do we do it? It’s all thanks to our Belden alternative cables. They’re identical in fit, form, and function to the industry’s leading brands but at a fraction of the price. Spec sheets are available on request.

Plus, you gain access to industry-leading customer service if you still need help selecting the right wire or have questions about the installation side of things. We’re always available to provide friendly one-on-one support.

Whether you’re wiring a residential building or outfitting a commercial setup, AudioVideoElectric.com is your trusted source for all things wiring. Shop today and see for yourself what separates us from the rest!

Bringing Our THHN Wire vs Romex Cables Comparison to a Close

That does it for our comparison of THHN vs Romex. In conclusion, both THHN wire vs Romex cables have their pros and cons depending on the application they are being used for. 

For general-purpose wiring indoors such as conduit or wiring embedded in walls or ceilings, THHN cable is an excellent choice thanks to its high-temperature rating and excellent protection against moisture and abrasion damage. 

However, if you're looking for a more affordable solution for residential projects like lighting circuits or outlets then Romex may be the better option due to its lower cost and ease of installation (no special tools required). 

Our blog has additional resources on topics like conduit fill calculator, how to test coax cable, how to splice coax cable, extending coaxial cable, what does RG stand for in coax, cable sizes AWG, and more. Or, check out some of our most popular collections below:

Whether you need THHN cables, Rolex cables, Belden alternative cables, bulk coaxial cables, or multi-conductor cable, AudioVideoElectric can address all of your cable and wiring needs, and do it at a very affordable price. Shop today!

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