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Help Anyone! I am sound proofing a hometheater and from everything I read I don't want to be punching holes in the sound proof walls. But my contractor said if they build columns or a soffit they need to nail them through the sound proof dry wall to the room frame. Anyway to avoid this because I assume this will allow sound transmission to the frame and therefore out of the room.
 

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Nails driven through the drywall won't be a problem. Holes cut through the drywall and left open will.


How do you think the drywall is being held to the wall? Nails and/or screws through it and into the studs behind.


-Suntan
 

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The drywall is decoupled by RSICs clips. So they aren't nailed or screwed directly into the frame.
 

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Nails are never a great idea. Small detail
 

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Get a different contractor, this one has limited intellectual horsepower and wants to build it like his grandfather taught him.

You can attach a soffit to a decoupled ceiling and wall structure without going into the framing.


Columns? they need minimal wall attachment and as long at they are standing on the floor just a few screws into the drywall (and not further) is going to keep them there. Think of them as a piece of furniture anchored to the wall. You can hide the attachment points at the top and bottom with molding. I actually attached blocking to the ceiling and the floor and screwed through the front of the column. Two screws on top, two on the bottom into the blocking.


If we had a picture of your room and proposed dimensions of the soffit we could get more specific.


If you had pre-planned this out a little more you would have located a hat channel directly where the soffit will mount to the ceiling and wall for additional support but it isn't 100% necessary.
 

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Certainly more details would be needed to address this. Have you discussed this with the supplier of the materials?
 

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Thanks.. unfortunately I can't switch contractors so I just have to educate him as I become educated. I will take some pictures and post them with the dimensions.
 

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OK here is what you have to tell the contractor. Instead of building a heavy framed soffit that is attached to a the wall and ceiling framing (like he has done all his life) you are going to need to design it as light as possible and attach it to only the drywall and hat channel where possible.


Screws, construction glue and maybe a few toggle bolts are what you are going to be using.
 

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Quote:
Originally Posted by puzzled /forum/post/16629362


The drywall is decoupled by RSICs clips. So they aren't nailed or screwed directly into the frame.

Apologies, I guess I was envisioning a staggered wall.

Quote:
Nails are never a great idea.

Not the best blanket statement to make. There are many instances in home construction where nails are a better option than screws.


-Suntan
 

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Quote:
Originally Posted by Suntan /forum/post/16631358


Not the best blanket statement to make. There are many instances in home construction where nails are a better option than screws.


-Suntan

Could you point out where? The only thing I can think of where I used nails other then screws was a fire rated metal door. The metal door frame was designed to be nailed. Oh, and trim -- trim would be hard to do with screws. Maybe some roofing and other exterior work, too. I also used some nails when building some framing for a door.


Other than these instances, I like screws. My house has incredibly squeaky floors and horrible drywall because of nails. Those problems would be ameliorated or elimated with srews.
 

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Your double door will be the weak link in all of this, unless you have have a similar door set to create an airlock when all doors are closed.
 

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Quote:
Originally Posted by ctviggen /forum/post/16648380


Could you point out where?

For the same basic “size” of hardware, the cross sectional area of a nail is larger than a screw. Also, the fluted structure and the process of rolling the screw threads produce significant stress concentration spots on the shank of a screw that nails do not have (unless you are using ring-shank nails.) These two factors make nails much more robust in areas where the fastener is loaded in shear.


Further, nails are allowed to flex and “give” (pull out) when the structure undergoes severe tension loads. Where as the shape and design of a screw (as cited in the previous paragraph) makes them much more likely to fail completely (snap/break) in a similar situation. For example, in a sever event (a tornado say, or a case where way too many drunk college kids significantly overload a deck) the slow/gradual failure (relatively speaking, it may still happen in the span of a second or less) of pulling nails out of joints requires significantly more energy than snapping a screw. The added energy required may well be the difference between a flattened house/deck and one that is just severely damaged. (If you don’t think it is true, nail 10 nails into a board and drive 10 similar sized screws into a board. Now take a pry bar and quickly pull the nails out with your right hand and quickly snap the heads off of the screws with your left, your arms will easily tell you which one had to do a lot more work.)


Lastly, nails are a lot cheaper and faster to install than screws.


-Suntan
 

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In general, screws are appropriate in a home theater given the unusual stresses the framing will encounter. Generally elements are screwed and glued to survive.


We have to take great care to make sure things stay tight. Hard surfaces need an intervening layer of caulk or adhesive so there's no chance of a rattle.


These noises unfortunately show up months later after things settle.
 

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I appreciate that Ted. I do have a rather extensive understanding of mechanical fasteners myself. I do not claim to say that nails are better then screws, as it is not universally true.


I was merely pointing out that your original statement was rather pithy to the point of being too general. Like it or not, people will tend to take comments you make as gospel around here and disregard most of the context surrounding it in the rest of the thread.


Saying, Nails are never a great idea can give people the wrong impression.


-Suntan
 

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Discussion Starter #18
I'm looking at building a 6in to 1 ft. soffit. Just enough to hide indirect lighting and maybe some cans and possibly the rear speakers. And maybe even the projector.
 

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If you can wait till later this week I will back in my office and can put together a napkin sketch and post it with the details of a soffit that size. You should have your room built prior to adding the soffit for the greatest sound proofing. Then a 2x2 can be mounted to the walls with liquid nails construction adhesive and drywall screws (not into the studs). Then a vertical stub wall can be built with metal framing (because it's lighter) and screwed directly to ceiling drywall. ( it's a good idea to put washers on the screws) If the hat channel for the ceiling is located directly over that location all the better. Then you have all you need to add lights and then drywall. Prior to adding the drywall the soffit should be stuffed with fiberglass insulation. I would use drywall adhesive in addition to the drywall screws.


There are other ways this is just one. You are correct to be concerned that the contractor might short circuit your isolated structure and unless you are on site supervising they just might. It is likely that the person who you discuss how things are to be done and agrees to the design will not be the person actually doing the work that day and they will revert to how they know how to build a soffit.


This is why so many of us have preferred to DIY.
 
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