Ul 723 vs Ul 181- Duct Tape Comparison

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There are literally tons of UL-tested and listed duct tapes available. Even some are better than the rest. But when two products are quite similar in nature, it’s tough to make the call.

That’s what happens when you try to compare ul 723 and ul 181.

So, what is the difference between ul 723 vs ul 181?

First of all, ul 723 goes through more rigorous lab testing than ul 181. That’s why it can resist fire and severe thermal conditions better. However, ul 181 has its perks as well. It can be found in different varieties and sizes. And the most important difference can be seen in the use cases.

I know you didn’t get to learn about the different usages. For that, you’ll have to come along with me through the whole journey.

So, let’s begin!

Key Differences Between the Tapes

I think you’re already quite aware of the different UL certifications and testing. They can be a tough read and hard to understand but quite necessary if you ask me. So, try to understand this basic HVAC concept. It’ll make the comparison seem easier to follow.

You can check out this simple explanation of UL certification-

Now, both the duct tapes have their strengths and weaknesses. I mean, without that, there wouldn’t have been any comparison in the first place, right? On one side, the UL 181 duct tape is made exceptionally well in different sizes.

On the other side, ul 723 duct tape is more robustly made but with fewer variations. Now, this might seem like a downside of ul 723, but I’ll urge you to be patient. 

For your understanding, explore this ul 723 vs 181 table to get a glimpse of the differences-

CharacteristicsUl 723Ul 181
Materials UsedMostly AluminumAluminum, silver, metallic
UL TestingMore rigorousLess rigorous
UsageFor any building materialsFor AC connectors

There are still several things left to be unraveled. So, let’s go straight to the full comparison now.

Full Comparison

I know you already got a glimpse of what you’ll be seeing ahead. Now, it’s time to get behind the discussion where you’ll be crystal clear about these tapes!

Materials & Sizes

Very frequently both the UL tested tapes can be made with the same raw materials. However, there are subtle differences you might miss noticing. I know you might think whether I’m nitpicking or not, but you’ll soon find out.

Many famous duct tape brands have their duct tapes tested under the UL benchmark. Most of the time, the UL 181 class 1 is made with different materials. For example, aluminum, aluminum silver, silver, metallic, and so on. So, you get many different offerings of duct tapes.

Even ul 181a aluminum foil tape is available in most local stores.

On the other hand, it’s hard to find all of the different variations of UL 723 duct tapes. Even popular brands like Nashua make aluminum silver duct tapes. Here’s a media company giving due credit to a duct tape that meets UL 723 standards-

Now, you can obviously find different material-based ul 723 tapes with some deep searching.

But that’s not the point here, right? Because it’s all about the products that you can easily find and use. So, the main focus should be on the available duct tape material found in the market.

So, in that category, ul 181 tape moves a bit ahead in the competition.

The same can be said for the size characteristics too. While the standard size for ul 181 is 2.5 inches, it can vary depending on the requirements. You can find all sorts of sizes starting from 48mmx55m, 48mmx110m, 48mm x 27.4m, etc. 

So, you don’t have to worry about your AC duct tape. Because these can easily go with your return duct for 3.5, 4, or 5-ton AC!

On the other end, you can get the same quality but with limited sizes for UL 723. They usually come in 48mm x 46m, 72mm x 46m, and 48mm x 9.1m sizes. As you can see, the sizes do have a contrasting difference too!

If you look at these two differences objectively, you’ll know the answer surely!

Winner: UL 18 definitely takes the cake in this ul 181 tapes vs ul 723 characteristics. 

UL Testing Procedure

Now, the tapes give away the testing process, don’t they? But do you really know what is the difference between ul 181 and ul 723? If you don’t then you gotta follow this one for sure.

Both the 181 and 723 UL testing is quite robust and rigorous. They go through several laboratory assessments and then get the final verdict.

Now the good thing about ul 723 rating and testing is that it’s more qualified. You might be wondering, “Does ul 723 meet a 1-hour fire rating?”

Yes, class-1 or class A ul 723 pass the 1-hour fire rating test. These class-1 tapes or insulators are the best when it comes to resisting fire. So, if some accidents occur, you won’t have to worry about your ducts or wires too much.

So, you get better resistance and thermal performance.

However, the ul 181 pales when compared to the performance of 723. You’ll have to give up a bit of fire resistance if you go with ul 181 tapes. 

But fire should be the least of your concern if you’re neglecting your air systems. Try to regularly clean the ducts with good cleaners. I personally use Interdynamics Certified A/C Duct Cleaner and SimpleAir Duct Fresh Gel

These are absolutely worth it!

Winner: Easily ul 723 duct tapes are more robust to use.

Use Cases

As per the official statement, ul 723 is more suited for any type of building material. It can be your wall, electrical duct, or literally anything. They are better thermal resistant too. So, you get more unified usage out of this type of duct tape.

On the other hand, ul 181 is made for air connectors and ACs. But they don’t have rigorous testing as opposed to ul 723 compliant tapes. That’s why the usage is a bit limited.

Many brands make these UL-certified duct tapes. But not all of them are good. If you’re undecided on which brand to go for, don’t worry too much. From my research, I’ve sorted out these popular offerings from Amazon-

Duck Brand 240225 HVAC UL 723Buy From Amazon
3M Aluminum Foil Tape 3340 (UL181A-P and UL181B-FX)
Buy From Amazon
Shurtape AF 100 UL 181A-PBuy From Amazon
The Original Duck Tape Brand 394475 Duct TapeBuy From Amazon

Oh, another thing. Both the duct tapes can be used for ductwork extension. But you obviously have to know how to do ductwork extension to the ceiling

Winner: UL 732 is better because of its versatile usage.

Which One to Stick to?

The final decision has to be taken now because you know everything about them. Still a bit confused about the differences? Let’s recap them briefly.

If you want to prioritize your duct-type material, then UL 181 is probably the one. The same can be said if you want more sizes and lengths. Because only UL 181 can be the one that fulfills those criteria.

However, those are only the strong points of ul 181 tapes. Most of the effective strengths can be found in ul 731. Because it can be used in most of your home appliances. On top of that, it’s more robust and resistant to fire and other severe conditions.

So, you can guess which one outweighs the other. Hopefully, with this summary, you’ll find the right tape you’ve been looking for.


What Does UL Listed Tape Mean?

The UL-tested tapes are made for both personal and commercial use. They go through extensive and rigorous testing for better heat, adhesion, resistance, and stretch durability. But don’t confuse them with UL certified as that’s a different category. So, they ensure your AC duct and building’s safety.

Can I Use Zip Ties on My Dryer Vent?

Yes, it’s quite possible to utilize the expandable nature of zip ties for dryer vents. While it can be a bit unconventional, it’s usable without causing any problem. Try to use the jumbo zip ties if possible as they are more robust. However, you’ll eventually need to change it after a few months.

Why is UL Listing Important?

Upon receiving the UL listing certificate, the duct tape has the official seal of approval. After the certification, the duct tape is ready to use, both commercially and personally. If any duct tape is not UL-listed, you should be careful about using them. Because they can cause hazardous incidents.


With that, the detailed comparison between ul 723 vs ul 181 comes to an end. 

However, if you want to go deep into the HVAC world, you can do that too.

So, now you’re all free to choose one according to your use!

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1 thought on “Ul 723 vs Ul 181- Duct Tape Comparison”

  1. Hi, as you pointed out, the UL181 did a relatively simple test. So, what kind of tests have been done, and can you list the test items? In addition, I saw the UL181 certification of some products, which only listed the product width and material without other test items. I wonder why?


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