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Discussion Starter #1
Hi, this is my first post!
I'm doing a ceiling reno in my mother's condo and I was wondering if I could get some advice on how to address the joist situation. It's an older building, probably built in the 1960's, with 8 inch joists spaced 12" apart. The room is 12x12, but only 7.8ft high.


Should I put the RSIC-1's directly on the wood furring, or off to the side directly to the joist?
 

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Remove the furring, attach clip to the joist, and run the channel perpendicular to the joist, like in SPC Ceiling Solution 3 here: http://www.soundproofingcompany.com/soundproofing-solutions/soundproof-a-ceiling/

You can save an inch if you block between the joists in a recessed fashion, then clip the blocks, and run your channel parallel with joists. Channel face should be 1/4" lower than joist to avoid any drywall touching the joist. This is more work, and only saves an inch... might not even be noticeable in the end.
 

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Discussion Starter #3
Remove the furring, attach clip to the joist, and run the channel perpendicular to the joist, like in SPC Ceiling Solution 3 here:

You can save an inch if you block between the joists in a recessed fashion, then clip the blocks, and run your channel parallel with joists. Channel face should be 1/4" lower than joist to avoid any drywall touching the joist. This is more work, and only saves an inch... might not even be noticeable in the end.
Thanks for the quick reply, Swervepf. So, removing the furring's not going to affect the structure's strength? I just don't want the joists to start moving around if I do that seeing that it's an old building. Also, would there be any fire code issues by removing the furring?
 

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post a picture of the furring to be sure we are talking about the same thing, Also just a FYI, Doing ceiling renovation in a multi-family dwelling usually requires Condo board approval and permits since it deals with the firestop design of the structure. You may be required to bring certain items up to current code now that you have removed the ceiling.
 

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Discussion Starter #5
There were 2 ceilings up there. I've only taken down the first ceiling so far and peeked into the joist cavity. I'm going to finish taking down the original ceiling this weekend. I'll have those pics for you by the end of the weekend.


Apparently the buildings were apartments originally and when they rezoned them for condo's they installed RC1 on 2x2 furring throughout. But they only used 1"x24" fiberglass sheets. So that left a 1" gap between the ceiling and the top of the fiberglass. The footfall noise was ridiculous.




i162.photobucketdotcom/albums/t250/Kafkaguy/ceiling2.jpg


i162.photobucketdotcom/albums/t250/Kafkaguy/bare%20ceiling.jpg


i162.photobucketdotcom/albums/t250/Kafkaguy/joist.jpg
 

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google "resilient channel problems and lawsuits" RC1 was prone to installation errors rendering it useless. Insulation is not a solution for footfall noise. Read the articles at soundproofingcompany.com on ceiling soundproofing. bottom line it is going to take Mass, Isolation, Dampening and absorbtion to solve the problem you may want to start by adding damped mass to the underside of the sub-floor above. Two layers of 5/8 srywall with Green Glued screwed to the sub-floor.
 

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Discussion Starter #7
Try these links for the pics. I just reset my photobucket security settings. Add the ".com" to the link.
i162.photobucketdotcom/albums/t250/Kafkaguy/ceiling2_zps67ff1d80.jpg
i162.photobucketdotcom/albums/t250/Kafkaguy/bare%20ceiling_zpseb92f1e1.jpg
i162.photobucketdotcom/albums/t250/Kafkaguy/joist_zpsa9d9844e.jpg
 

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Discussion Starter #8
You know, it's funny, now with that dropped ceiling gone, you can hear the footfall, but It doesn't resonate through the whole room like it did. Btw, that RC 1 was shorted out on the ends into the 2x2's.
 

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Discussion Starter #13
Ok, finished taking the ceiling down today. Here's what the joist's look like. Is it ok to remove the furring, or are they some kind of support and or fire break?


And if they are being used as support, could I remove just the ones (or part of the ones) that are in the way of my RSIC-1's?
 

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if you want my continued help answer the questions I've raised. Specifically Board Approval and attaching damped mass to the underside of the sub floor.
I also said no to RC1 and you continue down that path.


i don't like the look of how the joist space is wide open to the adjacent room from a fire break and sound point of view.
 

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Discussion Starter #15
I did answer your first question. You asked me to post a picture of the furring to make sure we were talking about the same thing.


Yes I have board approval. I talked to the association last week about it. She didn't say to pull a permit though.


The damping on the underside of the subfloor would be great, but it seems like it would get expensive since it includes GG. I would love to use it, but I don't have that kind of money in my budget. Also the original ceiling was only 1/2 inch and it didn't come off in good sized chunks, so I couldn't use that.


I'm not using RC1. I'm using RSIC1's with 25 gauge Hat Track.
 

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back to your question can you remove them?

Not sure why they are there, not a fire break, really don't add anything structurally other then possible stiffening the floor to minimize floor bounce for the tenants benefit above.

From the online reference tables I looked at, 2x8 floor joists spaced 12 inches on center are sufficient to handle the load for a 12 ft span assuming they are well supported on both ends so the furring isn't needed for that purpose. It may have been added to make it easier to hang the drywall. Allowable spans for the 2x8s would be around 14-15 ft depending on species and grade of lumber used.
 

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Discussion Starter #18
I finished installing the Roxul and some of the clips. Now, I have a dumb question. Should I use standard 24" oc spacing for the channels and cut to fit the middle sections (two 6' sections)? Or space the channels to use 8' sheets on each pass. going 8 and 4.5 then 4.5 and 8?
 

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