Soundproof Drywall: Does It Work & Is It Worth The Money?

Soundproof drywall does work and is a very effective noise control solution.

Soundproof drywall, also known as soundproof plasterboard or sound dampening gypsum board, has an extra layer sandwiched in the middle which is made up of gypsum, viscoelastic polymers and ceramic material.

Combined together these form a layer within the drywall that makes it very difficult for soundwaves to pass through, making it a very effective soundproofing product.

In this article will explore how cost-effective it actually is and where to buy it from.

What Is Soundproof Drywall?

Standard drywall made from gypsum is easy for sound vibrations to pass through due to its rigidity.

Soundproof drywall has a rubbery material sandwiched in the middle of its gypsum layers which deadens sound energy.

Soundproof drywall is typically made up of:

• Gypsum: a mineral made up of hydrated calcium sulfate. This is commonly used to make standard plaster of Paris.
• Viscoelastic polymers: this is the key material that separates soundproof drywall from standard drywall. It is rubbery in texture and it's structure changes when exposed to different frequencies. This viscosity helps it deaden soundwaves.
• Ceramic: clay mixed into the drywall helps give it greater density and strength.

Soundproof Plasterboard Available To Buy

Below are 4 great suppliers with a list of their best soundproof drywall products:

1. SoundBreak XP

Manufactured by the National Gypsum Company their Soundbreak XP range features 4 different products:

1. 1/2" SoundBreak XP Wall Board
2. 5/8" SoundBreak XP Wall Board
3. SoundBreak XP Retrofit Board
4. SoundBreak XP Ceiling Board

*Type X wallboard provides at least one-hour fire resistance when tested in specified building assemblies under controlled conditions. You can read more about National Gypsum's fire safety information here.

**Type C drywall uses a special type of Type X core which gives it a superior fire performance when used in certain fire-rated Type C assemblies.

2. QuietRock

QuietRock manufacture 6 different types of soundproof panel, listed below:

1. EZ-SNAP
2. EZ-SNAP Mold Resistant
3. QuietRock 510
4. QuietRock 530
5. QuietRock 530 RF
6. QuietRock 545

3. SilentFX QuickCut

Manufactured by CertainTeed the SilentFX QuickCut drywall is a strong performer.

4. ProSound (UK Only)

ProSound's Soundboards have been developed and improved upon numerous times since they first came onto the market back in 2009, their two latest products available for purchase are:

1. SoundBoard 4 System
2. SoundBoard 3 System

What You Need To Know About Soundproof Drywall

Understanding STC ratings, fire resistance, how soundproof drywall performs vs standard drywall and the cost differences involved are all key factors you should consider when making a purchase.

Sound Transmission Class Rating

The STC rating is the most important factor to consider when looking for soundproof drywall.

The rating tells you how well the drywall attenuates airborne sound. It is done by taking measurements of a sound on either side of a wall and measuring the difference between the two sides.

You can read more on how to calculate STC rating here.

The higer the number the better at soundproofing your drywall will be.

You will notice in our tables that we have given an STC range for each drywall product. This is because the drywall will achieve different STC ratings depending on how it is installed.

For example, if a stud wall has a gap in the middle so that either side of the wall is not connected directly to the other side this minimizes sound transfer and will result in a significantly higher STC rating than it would if drywall was connected to either side of the same studs.

Fire Resistance

Most soundproof drywall panels are Type X fire-rated which basically means that it will provide at least one hour of fire resistance.

There are a few panels listed which only provide 30 minutes, generally, fire resistance depends on the thickness and density of the drywall as well as the materials used.

Value For Money?

Depending on which type of Soundproof Drywall you buy you can pay between 5 and 20 (if you buy QuietRock 545) times as much as you would for standard drywall.

Soundproof Drywall is worth investing in for any project that is serious about stopping sound transfer.

It makes a significant difference.

Standard drywall installed on either side of a stud wall which is fitted out with 3.5 inches of Rockwool (or similar insulation) can be expected to achieve an STC rating of around 32.

This is 16 points lower than even the worst-performing soundproof drywall would achieve when installed on the same wall (48). The difference in sound transfer will be clearly noticeable.

You may be tempted to double, triple or even quadruple layer your standard drywall to try and achieve a higher STC rating however this can end up costing almost as much as some of the lower end soundproof products. You will also lose a significant amount of floorspace to drywall which isn't ideal and the labour costs for fitting 4 layers of drywall will add to your total cost too.

For commercial enterprises such as cinemas, theatres and music venues investing in high-grade soundproof drywall is an investment that is absolutely worth it because it gives far superior performance while maximizing available floor area.

Lower-grade soundproof drywall is still worth using for home soundproofing projects for the same reasons, more floor space, lower labour costs with good overall soundproofing performance.