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What are the latest thoughts on sound proofing be/t rooms? All my bedrooms
are separated by closets–should they still be insulated for sound?
Preferred material?
A powder room has 6″ walls built of alternating 2×4’s to isolate sound on
the one side of the wall from the other side. Is sound proofing insulation
still recommended? Never having lived in a house with interior insulation,
it’s hard to tell in the abstract what difference it makes and whether or
not it’s worth the cost. T
Replies
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Jim; Having recently visited a friend's remodel, some observations:
bat or roll insulation is relatively inexpensive(unfaced),and is installed quickly in walls.
soundproofing may not describe the effect so much as sound-deadening.
Maybe the Lugano Lake construction crew could blow some cellulose...
Best!
*To supress sound within a given area, use soft, thick materials to absorb the energy.To keep sound from going somewhere else, put as much mass in it's path as possible - a foot of concrete does very well.
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Looking for details on "soft, thick materials". Which is better: fiberglass or cellulose or polyurethane or something else? Which gives you the biggest bang for the buck (or I guess the _smallest_ bang)?
Just trying to afford some privacy to bedrooms and bathrooms. Trying to find out if sound-deadening efforts in a normal residential situation are worth the expense before I close in the walls.
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Did my lake home a year ago. I used fiberglass bats. It makes a big difference. Almost didn't do it but so glad I did. Yes, do the closets too. It really does not cost that much and this is your only chance.
*Fill your walls in all the way. Solid sheet rock. Solid foam board - the denser the better. If possible, make the walls thicker than normal. Make sure that outlet and switch boxes or air vents are not directly across from each other. That will create a sound conduit.Bathrooms are difficult to supress the sound inside of because of all of the hard surfaces that reflect sound. Luckily, it is not a place where loud noises are produced. To reduce sound as much as possible include as many soft surfaces as possible. Decorations of cork or cloth. Acoustic, drop ceiling. Put the exhaust fan at the end of the vent pipe instead of in the ceiling. Thick floor mats.
*If I'm not mistaken, noise is actually vibrations that make it to our ear drums. Eliminate the vibrations (or the pathway) and reduce the noise. Your easiest solution would be to use thinner studs than the top and bottom plates and stagger them.(just like the bathroom "wet wall"). This stops the vibrations by not having a continuous conduit for them to resonate through the wall. I'm not sure the insulation idea or the staggered studs will make that much "extra" difference to be "worth" it. You say that you already have closets separating the bedrooms? Won't the mass of the clothing and the zig-zag config of the walls break up the vibration enough? One other bit of advice, try to make sure that the outlets that service adjacent rooms aren't located in the same stud bays, (for obvious reasons, but sometimes overlooked) and since they are a breach in the wall, insulate around them well because they do allow sound to penetrate the wall.Should we be asking if you have a teenage son with an ear for loud music? If so I recommend framing his room with 2X6 studs on 2X12 top and bottom plates filled solid with blown-in cellulose!Good Luck
*As a cost effective solution I prefer to just fill the interior walls with the same insulation used in the exterior. That means the same crew can just keep going. Then take some care to keep openings in opposite sides of the walls out of alignment. If you have forced air I like to insulate the ducts in and out of that room even though they may not need it. Definitely insulate the DWV downstream of bathrooms.Short of lots of expense and maybe construction of a anoechoic chamber like room this seems to do the job of isolating noise, or at least bringing it down to the point where no one minds anymore.
*Inside walls you would like to use something denser than regular fibreglass thermal insulation which I believes runs around 1.5 pounds cu ft versus acoustical batts that run around 3 lbs cu ft.Also air tight construction. Use exterior doors with weatherstripping. Watch out for ducts short circuiting all your efforts. Electrical boxes also like mentioned above. Resilent channels work much better with airspace behind - applied on studs not over drywall. Also fully loading them helps - like 5/8" or double 1/2". Install according to directions or you'll loose a lot of the benefit.Fully adhere multiple layers of drywall - compound and a notched trowel.You can do ok with 2X4 studs. Double drywall one side; batts; resilent channels and double drywall opposite. A friend who was corporate acoustician at USG did this around grandson's room - removed drywall one side; fitted pcs in between studs and adhered with compound; batts; resilent channels; "hung" strips off channels (between them); and them applied a full layer over channels. Added less about a half inch to wall thickness but achieved better than 60+ STC - not quite recording studio sound proof but darn near.This whole process is definitely a "weakest link" prospect. Everything has to be done well.And if you have thin floors/ceilings and joists or trusses running perpendicular to wall - you may not be able to achieve much isolation without blocking this flanking path.
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try applying a course of 1/2" foam panel to the studs prior to sheetrock. electrical boxes have to be moved out off stud face additional depth of foam panel. I use Celotex Tuff-R 7/16" 4x8 panels.
foil faced, light, easy to cut. just tack on with a few roofing nails, rock screws will do the rest.
wood transmits heat and sound, so foam works better than fiberglass batts in walls. has r3.6 value, which increases to r7 with use of fir strips, good for ceilings
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What are the latest thoughts on sound proofing be/t rooms? All my bedrooms
are separated by closets--should they still be insulated for sound?
Preferred material?
A powder room has 6" walls built of alternating 2x4's to isolate sound on
the one side of the wall from the other side. Is sound proofing insulation
still recommended? Never having lived in a house with interior insulation,
it's hard to tell in the abstract what difference it makes and whether or
not it's worth the cost. T
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Rigid foam is an excellent conductor of sound. Some of the worst - for sound critical spaces -roof construction is metal deck with foam with epdm. Just awful.