Author Topic: Plans to soundproof ceiling - need help  (Read 4601 times)

Stephanie

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Plans to soundproof ceiling - need help
« on: June 18, 2003, 08:20:12 PM »
Bob- I intend to call you soon - but wanted to post this for the benefit of others.

I own a 2-flat in Chicago - I live on the 2nd floor, my tenants on the 1st floor are planning to move out in August, so I'm using this opportunity to soundproof.

It seems like the most effective option would be to float the ceiling in the 1st floor apartment to lessen the impact noise from my apartment above. There is also quite a bit of vibration/structural/impact noise that I hear and feel when the kids downstairs run around. So after I tear the current ceiling down, I want to fill the joists with some of the closed-cell foam to absorb some of the sound/vibrations.

Questions I have:
1) I'm guessing the current floor/ceiling assembly is in the STC 20s. How many STC points will I add by floating the ceiling, plus adding the closed-cell foam.

2) what thickness closed-cell foam should I use? I see thicknesses ranging to 2 inches. What are the STCs of the different thicknesses?

3) How should the closed_cell foam be applied? I see there is some sort of adhesive? How much of the joist should it cover?

4) In installing the floated ceiling, i've seen that the sound clips should be installed 16" or 24" on center. what does on center mean? Also I've seen that 24" on center is better because there's more spacing (and less possibility of impact noise traveling I would assume)

5) When the drywall for the new floated ceiling is installed, I've read that you shouldn't have the new ceiling touch the wall drywall - you should leave a gap and just use acoustical caulk in that gap - I assume to further lessen impact noise. Is this true? and can it be painted over so that the caulking isn't so obvious?

6) Lastly, I would like to hire someone to do this, or at least help me do this. I have been having a hard time finding anyone. The acoustical contractors around here do mostly commercial work. Any tips of who I can contact - whether a specific company, or type of company - (drywall contractors? general remodelers?) - I really want to get someone who knows what they're doing -

Bob - as always - thanks for your help - this is important endeavor for me (as I've endured tenant noise for 4 years, and don't want to do it anymore) -

Stephanie

Boborther

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Re: Plans to soundproof ceiling - need help
« Reply #1 on: June 20, 2003, 03:11:48 PM »
Stephanie,

I will try to answer your questions in the order in which you asked
them. I will be brief, and if you need more details you'll need to
call me. Thanks Stephanie.

Bob- I intend to call you soon - but I wanted to get some initial
answers. I also posted this on the forum, so if you want to respond to
me there (so that others can see it) - that would be great too.

I own a 2-flat in Chicago - I live on the 2nd floor, my tenants on the
1st floor are planning to move out in August, so I'm using this
opportunity to soundproof.

It seems like the most effective option would be to float the ceiling
in the 1st floor apartment to lessen the impact noise from my
apartment above. There is also quite a bit of
vibration/structural/impact noise that I hear and feel when the kids
downstairs run around. So after I tear the current ceiling down, I
want to fill the joists with some of the closed-cell foam to absorb
some of the sound/vibrations. THIS IS A VERY GOOD IDEA FOR ABSORBING NOISE AND VIBRATION, I WOULD GO WITH AT LEAST 1/4" FOAM MAT, THICKER
WOULD BE BETTER OBVIOUSLY.

Questions I have:
1) I'm guessing the current floor/ceiling assembly is in the STC 20s.
How many STC points will I add by floating the ceiling, plus adding
the closed-cell foam. IF YOU USE THE SOUND CLIPS AND FURRING CHANNELS WITH ONE LAYER OF 5/8" FIRE CODE DRYWALL, YOU WILL ADD APPROXIMATELY
38-40 STC POINTS,
IF YOU USE RESILIENT CHANNELS  (RC-1) AND THE 1 LAYER OF 5/8" DRYWALL, YOU ARE LOOKING AT ADDING 18 TO 20 STC POINTS. AS YOU CAN
SEE, THE SOUND CLIPS DOUBLE THE SOUNDPROOFING OVER THE (RC-1)

2) what thickness closed-cell foam should I use? I see thicknesses
ranging to 2 inches. What are the STCs of the different thicknesses?
AT LEAST 1/4"  BUT THE THICKER THE BETTER, AS WITH ALL SOUNDPROOFING.

3) How should the closed_cell foam be applied? I see there is some
sort of adhesive? How much of the joist should it cover?  I WOULD
PURCHASE THE CLOSED CELL FOAM SANS THE ADHESIVE BACKING AND SIMPLY USE CONTACT CEMENT TO ADHERE THE FOAM TO THE CAVITIES AS WELL AS COVERING THE ENTIRE JOISTS.

4) In installing the floated ceiling, i've seen that the sound clips
should be installed 16" or 24" on center. what does on center mean? TO
THE CENTER OF THE JOIST
Also I've seen that 24" on center is better because there's more
spacing (and less possibility of impact noise traveling I would
assume) THAT' S PARTIALLY CORRECT, HOWEVER IF THE FLOATED CEILING IS GOING TO BE MORE THAN ONE LAYER OF DRYWALL, YOU WILL NEED A SOUND CLIP
ON EVERY JOIST 16 OR 24 ON CENTER. REMEMBER, THAT WITH A CEILING, THE SOUND CLIPS AND THE FURRING CHANNELS ARE WEIGHT BEARING.

5) When the drywall for the new floated ceiling is installed, I've
read that you shouldn't have the new ceiling touch the wall drywall -
you should leave a gap and just use acoustical caulk in that gap - I
assume to further lessen impact noise. Is this true? and can it be
painted over so that the caulking isn't so obvious? YES, THERE MUST BE
A 1/4" GAP LEFT AROUND THE ENTIRE PERIMETER OF THE NEW FLOATED CEILING, IT WILL BE CAULKED WITH ACOUSTICAL CAULK AND FINALLY YOU
WOULD TAPE MUD AND PAIN THE NEW FLOATED CEILING .

6) How much should closed-cell foam/sound clips should I estimate to
order? The apartment is about 1500 sf. STEPH, THAT WILL TAKE SOME MEASURING, AS YOU NEED TO MEASURE THE CAVITY AREAS AS WELL AS THE
JOISTS THEMSELVES, TO MAKE SURE YOU HAVE ENOUGH MATERIAL TO COMPLETELY LINE THE ENTIRE CEILING AND JOIST AREAS.

7) Lastly, I would like to hire someone to do this, or at least help
me do this. I have been having a hard time finding anyone. The
acoustical contractors around here do mostly commercial work. Any tips
of who I can contact - whether a specific company, or type of company
- (drywall contractors? general remodelers?) - I really want to get
someone who knows what they're doing - STEPHANIE, BASICALLY ANY GOOD DRYWALL CONTRACTOR CAN DO THIS WORK, AND THEY ARE WELCOME TO CALL ME
FOR ADVICE AND TIPS FOR INSTALLING THESE PRODUCTS.
LASTLY, I WISH TO COMMEND YOU ON THE MARVELOUS RESEARCH YOU DID FOR YOUR PROJECT. I AM TRULY IMPRESSED WITH THE INFORMED AND INTELLIGENT
QUESTIONS YOU ASKED. IT SHOWS THAT YOU DID YOUR HOMEWORK STEPHANIE.
 I LOOK FORWARD TO HEARING FROM YOU SOON. THANKS FOR THE POSTING.

Bob Orther
Super Soundproofing Sales /Technical Associate
www.soundproofing.org
boborther@soundproofing.org
Phone (760) 749-7049
Orders only!  (888) 942-7723

Kathleen Austin

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Re: Plans to soundproof ceiling - need help
« Reply #2 on: April 19, 2004, 01:09:31 AM »
Stephanie - I know you posted this quite a while ago but I am hoping you still might respond to this inquiry.  We also have a 2-flat in Chicago that we are planning on doing a bit of soundproofing in this year.  Did you ever find a contractor?  If so, is it someone you would recommend?

Kathleen

 

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