Adding soundproofing/insulation to interior walls
mzwolinski
| Posted in Energy, Heating & Insulation on
I just recently moved into a new home, and the builder installed 1/2″ drywall throughout the house. On the exterior they put fiberglass batts but nothing on the interior walls. The hollow stud space with 1/2″ drywall seems to almost magnify the sound from the next room. What can I do to add some soundproofing to my interior walls to help quiet the house short of tearing the drywall out of my new house. Thanks!
Replies
You could get cellulose blown in. It would involve drilling (and then patching) holes in each stud bay. Or fasten foam to one side of the wall and cover with another layer of drywall. Or simply glue on another layer of drywall (without anything in-between).
You can blow in cellulose as suggested but you need to be aware that some interior stud bays are part of the HVAC system. If that is the case, you cant insulate them with anything....
The other thing you could do it lay off the $ tacos on Taco Tuesday......
cussnu2 wrote:
You can blow in cellulose as suggested but you need to be aware that some interior stud bays are part of the HVAC system. If that is the case, you cant insulate them with anything....
The other thing you could do it lay off the $ tacos on Taco Tuesday......
Excellent tip on the possibility of air returns etc in the reply. It’s something professionals would look for and see but might slip their mind in an online reply.
nicely done.
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Note that for sound dampening you don't need to hit every stud bay. Roughly every other bay would be sufficient.
An empty house always sounds loud, especially if you have wood floors. Interior walls are very rarely soundproofed but if you have to the first thing is to seal cracks with acoustic caulk. Do all around the room where baseboard touches the floor, around electric outlets and any other wall penetrations. The most important area will be doors into the room. They should be soild, have vinyl seals around the edges and a threshold at the bottom. If that isn't enough add 5/8" drywall on top of the existing walls, sealed with acoustical caulk. Mass is your friend when you soundproof.
There are two issues w/ sound: sound transferred through physical contact of structure/physical elements (e.g. studs, sheathing, drywall) and sound transmitted through the air. 'Soundproofing' addresses each separately. Cellulose isn't really designed for sound (sound batts are) ... but is better than nothing and a reasonable choice. Separation of physical components uses 'resilient channels' to physically separate framing from drywall. Another approach is to add mass (e.g. another layer of drywall). I worked in a concrete office near a military air strip and often would not hear planes close by.
Read up on 'soundproofing construction' ... there are some good videos on youtube. Also study STC ratings that I think are available through the Gypsum Association or some local code officials will give you construction details that usually combine, sound insulation, separation, and mass. The details provide STC ratings under various conditions/materials. You might pick some hints for options for you.
Adding another sheet of drywall with either the special non sound transferring clips or with the Green Glue sound dampening liquid that is applied with a caulk gun is the approach taken for sound studios or home theater rooms. You would only need to do this on one side of a wall.
Floor and wall coverings make a tremendous difference in how "live" a room will be and carpeting is better than a wood or linoleum or tile floor. Drapes also help with reducing sound transmission.
Adding more mass to the walls unless you use concrete is not going to help. Lots of soundproofing information on audiophile and home theater websites.