Next we layer the gyp board over that in a vertical orientation. We bond the Sound Stop to the framing using an acoustical sealant running horizontal to the framing.

We practically make this our SOP in walls between master baths and nurseries / adjoining bedrooms, etc. Go figure.Īlso, if you're going to go the 'double board' route then consider three other options in lieu of gyp board only.įirst would be a product from Celotex called Sound Stop: On the other hand, a great deal of work has been done by the NRC of Canada (finest acoustics lab in North America) gives us the data that shows cheap ol' fiberglass is actually the way to go. Surprisingly, the insulations that market themselves as 'acoustic' have no lab data that supports they are a better choice. Since fiberglass has the edge there, we use it. It will have low frequencies as the only significant frequency issue. Mineral fiber has a slight edge in the upper frequencies, but that wall will not have high frequency issues. Why? Because it works best in the low frequencies. If the walls were not drywalled, your best route would be standard R13 fiberglass. Just take care that the insulation doesn't get compacted during installation. Since the wall is already drywalled, you're limited to blown-in cellulose or perhaps fiberglass. The framing limits the contribution of the insulation. Interestingly, insulation in a single stud wall is good, but not great. If you are going to the effort to add a second sheet of drywall (5/8' is best) then it would be a missed opportunity to also damp the wall with Green Glue.

Mass loaded vinyl over drywall