This is a very common question. There are several manufacturer’s of quality pre-damped drywall marketed for sound isolation. So is this a good product or a good idea? The short answer is “yes” to both.
Any pre-damped drywall (there are many manufacturers) is simply layers of standard board that you can buy at Home Depot(drywall or cement underlayment). Between those boards they sandwich some type of damping compound. There is simply no mystery to the materials. So the decision to use these pre-damped boards comes down to:
- Price (less is better)
- Mass (more is better)
- Damping (more is better)
Generally you will always be able to field assemble a more massive, more damped and significantly less expensive wall or ceiling. An additional plus is that field assembly will allow you to overlap seams between the drywall layers.
In general, any manufacturer will put their best foot forward when marketing their products. In the case of the expensive $120+ pre-damped drywall, their best foot certainly isn’t price, so they show you the great test data. In the case of the $50 drywall, the test numbers are not very encouraging, so we instead see them describe the price. Their hope is that a consumer assumes performance.
So what’s the difference between a $50 damped drywall panel and a $120 panel? Generally it’s the amount of damping compound in the board. Less compound = less damping = lower performance = less cost.