Does Rockwool Sound Insulation Work?

Many of you have probably heard of Rockwool batts and boards before.

But you’re wondering if it works well for sound insulation or not. The short answer is: YES. It works really well for sound insulation, thermal insulation, plus it’s fire resistant.

It blocks sound better than most glass wool insulation products because it’s made from non-directional fibers which trap airborne noise to a larger extent.

Rockwool batts are commonly used during construction, and they’re placed between walls and floors for additional insulation. The installation involves stuffing the batts between the wall studs.

You can imagine why this application works well. All of that empty space between the studs is suddenly occupied by thick rock fibers. Yes, that’s the secret to the sauce.

So are there any downsides to Rockwool? Yes, there are:

1. It can irritate skin

This was especially true with older Rockwool products. New batts and boards are relatively safe. But it’s still recommended to use gloves, glasses and a mask over your nose and mouth when using it.

It’s because Rockwool can emit small rock fiber particles that can irritate the skin and respiratory system. But this problem is easily solved by using basic protection gear that I just mentioned.

2. It can’t be installed on open surfaces (unless..)

Since it can be irritating for skin and lungs, you can’t install these batts and boards directly on the wall, which is a possibility with other soundproofing materials such as mass loaded vinyl and closed-cell foam.

However, there’s one way to surpass this obstacle. By covering the Rockwool material with a dense fabric cover, it’s possible to install it on any surface, just like a regular acoustic panel and with zero irritation.

I’ll end this article on a high note by explaining some of the benefits of using Rockwool:

1. Simple installation

All it take to install Rockwool is to place it between studs. Or if you plan on using it outside, first use a dense fabric cover and then hang it with hanging strips or a spray adhesive to any surface.

Rockwool batts are also small and light enough to be handled by one person. Here’s a very useful installation tutorial:

2. Fire retardant and water resistance

Rockwool is really effective against fire AND it’s waterproof. You can try an experiment: fire a blowtorch or a lighter on it and see what happens. If you got the right material, it will merely glow for a bit.

This is a big security measure against fires, because it can prevent or drastically slow down the spread of fire through the walls in case of an accident.

3. Price

Rockwool insulation is usually more affordable than soundproofing materials that are designed for on-surface installation.

So if you’re looking for a way to soundproof a wall on a budget, get Rockwool batts and cover them with a dense fabric to prevent irritation, and then install them on the surface using hanging strips or a spray adhesive. It’s cheaper and you’ll get awesome insulation by doing it.

I don’t recommend this method often because most people aren’t willing to go through the extra hassle. But if you got some extra time and want to save some money in the process, it’s definitely a viable option.

Final Thoughts

Rockwool batts (available on Amazon) are an often used material during the construction of walls and floors for better sound insulation. But still, many times zero sound insulation is used despite of the common regulations that require it.

So opening the wall and placing the batts in there yourself if they’re not present already is worth it. Or making DIY acoustic panels for direct on-surface installation.

I hope this information helps and feel free to check other articles on my website for more sound(proof) advice.