On one of our projects the developer is insisting that acoustical sealant is only necessary at the top and bottom of a partition, we have specified it for the complete perimeter of the partition - anu Acoustical Experts out there who would care to comment.
If you look at Gypsum Association GA-600, Section III has four pages on sound control, including details. The first sentence says “The first essential for airborne sound isolation using any system is to close off air leaks and/or flanking paths by which noise can go through or around the system.”
If that isn’t clear enough, later on, in big bold letters, it says: “ALL OPENINGS THROUGH THE SYSTEM, AND ITS ENTIRE PERIMETER, SHALL BE SEALED AIRTIGHT.”
And there are several details showing sealant at the entire perimeter.
The GA-600 on my desk is the 16th edition (2000) and I am looking on page 14 and 15. Seems clear enough to me, but I am not an acoustical expert.
I’m sure no expert, but you also want to seal around openings and cutouts (eg around ducts and other penetrating items), and sides and backs of electrical boxes to completely close off openings and joints
The first principle of acoustics that I learned 20 years ago: If the room won’t hold water without leaking is it not acoustically tight.
Seal anything that air could move through. A pinhole will drop the acoustical value of an assembly significantly.
Jerry,
I agree with George, the Gypsum Construction USG Handbook says “If gypsum board assemblies are to effectively reduce the transmission of sound, they must be airtight at all points. To achieve this, perimeters must be sealed with Sheetrock Brand Acoustical Sealant…”
Another common error…they always incorrectly seal under the runner instead of the correct way on the side of the runner.
If the partition butts other drywall where it is all taped together, you would not need acoustical sealant. Where the partition abut other materials, you clearly would. Maybe there is a misunderstanding about what consitutes the perimeter.
Thanks guys
My argument (with this forum’s help) satisfied the Owner’s rep…now on to the next problem.