I have read most if not all of the content on soundproofingcompany.com and have learned a lot, but I still have a few questions about how far I should go with attempting to soundproof my theater from the rest of the house.
My new (to me, built in 2003) home has a finished walk-in attic that is currently being used a crude home theater above the garage that I want to finish and soundproof. I have attached floor plans of the first and second floor of the area as well as a couple of photos of the space as it is currently.
I have not yet been able to do any testing to determine the current state of the sound isolation from the rest of the house, but I imagine it is somewhat decent given the fact it is over the garage and on the opposite side of the home from the master bedroom. Still, just about any noise from the theater is going to be too much for my wife and newborn we are expecting in August (nursery is next to master on opposite side). I have 2 Epik Empire subwoofers as well as separately amplified tower speakers, so the system will be capable of some relatively-serious SPL. I realize that 100% noise reduction is probably not feasible, but I want to come as close as I can reasonably get. In other words, I am wondering what would it take to be listening at reference level in the theater and the rest of the house never know.
Obviously, I would prefer not to rip down all or most of the drywall to decouple, but if it is going to make a huge difference, I guess I will.
If that is not going to be a game-changer, I think I would plan on just adding a wall (I would guess staggered stud?) where I drew the red line with another solid core door with an automatic door seal at the bottom with 2 sheets of drywall on each side with green glue.
I think the next most important surface would be to soundproof the floor by adding mass. Would a layer of green glue over the existing plywood and then another sheet of plywood do the trick? Or should I also do a serenity mat first or something else?
What about sound flanking otherwise? Would it make sense to also do the walls and sloped ceiling where I marked in blue since that somewhat faces the rest of the house?
Thanks so much for your input in advance.
Second floor plans:
First floor plans:
Hallway and door into finished attic with sloped ceilings:
View of existing door and area where staggered stud wall to be constructed and door added as described above:
View of same area from opposite side:
View of location of screen and seating area with existing door at left: