How to Choose 9mm, 12mm, or 24mm PET Acoustic Panels?

9mm, 12mm and 24mm are the three most common thicknesses you will see when sourcing PET acoustic panels. One question we hear quite often from customers is: Which thickness should I choose for my project?

If acoustics are not your main concern and you are using PET panels mainly for decorative purposes, the choice is quite simple. You can choose the thickness that works best for your design and budget.

But if sound absorption matters, the answer becomes a little more complicated. I wouldn't simply tell you that a 24mm panel is better than a 9mm panel just because it is thicker. Thickness does affect acoustic performance, but it is not the only factor that matters. The GSM of the panel and installation method behind the panel and even how much of the space is covered in this room can all make a difference.

So rather than simply saying “24mm is better than 12mm,” it makes more sense to look at what you are actually using the panel for.

9mm PET Acoustic Panels

9mm is a very common thickness for PET felt panels, especially when the material will be used on walls or processed into finished acoustic products. It is relatively light and easy to work with. For many projects, the main reason for choosing 9mm is not that it needs to provide the highest sound absorption. It is because it gives a good balance between acoustic function, availability and budget. 

We often see 9mm used for wall panels, decorative acoustic features, office applications, CNC-cut designs and V-grooved panels.

If you are buying PET sheets for further processing, 9mm is usually one of the first specifications worth looking at.

What Changes When You Move to 12mm?

The difference between 9mm and 12mm doesn't sound like much. And they have the similar sound absorption effect. But once you have both panels in your hands, the difference is quite obvious. 12mm feels thicker and more rigid than 9mm.

So when should you choose 12mm? If you want a stronger and more solid panel, 12mm is usually a good option. We see it used a lot in offices, meeting rooms, schools and other commercial spaces.

If you're choosing between 9mm and 12mm and don't know where to start, I would say 12mm is a very practical choice. It gives you more thickness and rigidity, but it's still easy to cut, groove and fabricate into different designs.

But I wouldn't say 12mm is always better than 9mm. If 9mm already works for your application, there is no need to pay for extra material you don't really need.

When Does 24mm Make Sense?

24mm is a different proposition. 24mm polyester acoustic felt can be useful when stronger sound absorption is required, such as 

concert halls and theaters. And we often use 24mm PET acoustic felt as ceilings in commercial space because a thicker panel allows you to create more dimensional wall and ceiling features and gives the finished product a much stronger physical presence.

We would normally look at 24mm when acoustic performance is a bigger part of the project requirement, or ceilings or when the design itself calls for a thicker material. But again, we would not recommend choosing 24mm simply because “thicker must be better.

For some projects, that would just add unnecessary material and cost.

Does a Thicker Panel Always Absorb More Sound?

Generally, a thicker PET acoustic panel can provide better sound absorption, especially at certain frequencies. But I wouldn't compare two panels by thickness alone. How you install the panel matters a lot.

For example, take the same PET acoustic panel and install it in two different ways: one directly against the wall, and another with an air gap behind it. You may get very different acoustic results. So if sound absorption is important for your project, don't just ask the supplier: What's the NRC? Ask for the acoustic test report and take a quick look at how the panel was actually tested.

Was it installed directly against the wall or with an air gap? If there was an air gap, how deep was it? What thickness and GSM was the tested PET panel? These details matter. Otherwise, you could be comparing two NRC numbers that were tested under completely different conditions.

9mm vs 12mm vs 24mm: A Quick Comparison

One More Thing: Don't Ignore GSM

Thickness is easy to see, so naturally it gets a lot of attention. GSM is less visible, but it is worth checking.

Even if two panels are both 9mm thick, they may not actually be the same product when the weight is different.

For example, one supplier may offer a 9mm PET acoustic panel at 1850gsm, while another offers 1600gsm. That difference in GSM can affect the sound absorption, the material cost, and even how the finished panel looks after V-cutting processing.

You can see the difference more clearly when the panels are cut or grooved into patterns. A 1850gsm of 9mm PET panel has more material and usually gives you a denser, more solid finish. The cut edges and grooved patterns tend to look cleaner and hold their shape better than on a 1600gsm panel. So when you're comparing prices for 9mm PET acoustic panels, don't compare thickness alone. Always check the GSM as well. A cheaper 9mm panel may simply have less material in it.

PET Acoustic Panels from Jiadian

Jiadian manufactures PET acoustic panels in 9mm, 12mm and 24mm, as well as customized specifications for different customers in China. If you're not sure which thickness you need, don't worrt. Tell us what you're making, where the panels will be used. We will suggest it for you.