# Workshop sheeting/soundproofing



## ADHDan (Aug 17, 2012)

I'm setting up shop in a 12' by 18' space created by walling off a section of my laundry room, and I'm looking at sheeting the 18' wall which is shared by the family room. The shop wall is currently unsheeted, i.e., I'm looking directly at the wall studs and the back of the family room paneling (it's not drywalled). For reference, this is a split-entry house with lower-level family room and laundry room/shop, and the shop has two interior walls (adjacent to the family room and the laundry room) and two exterior concrete walls. I have a few questions:

(1) For the 18' wall, I'm leaning towards using fiberglass insulation behind 1/2" plywood behind 5/8" drywall. My goals are to create a decent sound barrier and to provide a strong surface for hanging items on the wall without always having to find a stud or bank on anchors/toggle bolts. Does this approach seem reasonably cost-beneficial?

(2) Currently, the 12' dividing wall (sectioning off the laundry room) is unsheeted on the laundry room side, and sheeted with 1/2" drywall on the shop side. If I use fiberglass insulation and 5/8" drywall when I sheet the laundry room side, will that be sufficient for soundproofing? Or should I add another layer or do something else with the shop-side wall?

(3) What is the best way to soundproof the shop-to-laundry room door? The dividing wall is roughed in and there's a small but visible gap between the door frame and the studs/drywall, so I assume I'll need to fill that in and put some sort of sheeting or trim over it. I also assume I'll need to do something along the floor line, since the door is about 1/4" off the floor. And I may even need to replace/modify the door, since I think it's a frame/panel job with top and bottom panels.

(4) The ceiling is also unsheeted, and I'm looking up at exposed electrical/plumbing/HVAC lines. Obviously, this will be a major source of sound transmission that will need to be fixed eventually. I can put up (or contract out) insulation and drywall on the ceiling, but there's a large HVAC duct that drops below the joist line. What's the most cost-effective way to soundproof that duct? Should I rough in short studs around the duct and just insulate/drywall along it, or is there a better solution?

Although I've been woodworking for a little while now this is my first foray into home improvement, so any advice is appreciated (and I apologize for any imprecise/unclear descriptions). Also, for all of the above cost is something of a factor, so I'm looking for an optimal return on investment at a decent price (rather than paying top dollar for the best soundproofing imaginable). Thanks!


----------



## crank49 (Apr 7, 2010)

You could use rigid fiberglass or rockwool for sound insulation. O.C. Rigid Fiberglass can be hard to find sometimes. But so can the Rockwool. So, I'd say either one would work. And they're both better than the "fluffy pink stuff" which really doesn't do squat for acoustical absorption.

There is a special sheetrock (drywall) intended to be a sound barrier. Normally done with two layers and special clipe between them.

For the long wall, where you want to provide structure for mounting things, i would suggest either plywood or OSB (oriented strand board, or chip board). i'm planning a new shop right now and I am considering 3/8 plywood or 7/16 OSB. The OSB is is about $10 per sheet and the plywood is about $20, but, of course the plywood looks better.


----------



## Whiskers (Nov 6, 2012)

Personally I wouldn't want to rely on OSB to hang anything of any real weight and chip board is useless. And you mention laundry room, which means moisture in the area, which is bad for any man-made material. Consider a vapor barrier. Ordinary insulation is lousy for sound deadening. Styrofoam helps more but is expensive. That said, Anything is better than nothing. If you have appliance rental places near, or know someone who works at a big box store, you can get Styrofoam from them as they unpack appliances and deliver them.


----------



## crank49 (Apr 7, 2010)

Whiskers, Around here, some builders refer to OSB as chip board or flake board, different names for the same thing. Maybe you are thinking I was refering to particle board. I agree, that stuff is useless.

According to building code, OSB can be equal to plywood for strength. I was also comparing 7/16 OSB to 3/8 plywood, so the OSB in this case would be stronger than the plywood. Many people I know have used OSB for shop walls for the very purpose the OP suggested; "hanging things without having to always find a stud." It works quite well. Since the OP wants to cover the plywood wall with sheetrock, the appearance of OSB as a substitute would not be a problem; it would be hidden, and it would offer equal strength for half the cost..

I also did not recommend the OSB or plywood for the laundry room. I specifically pointed out the long shop wall. I think, since the laundry room wall is already sheet rocked on the shop side, I would add top layer of sound dampening sheet rock on the shop side and then insulate the wall with 3" of rock wool and finally a single layer of sheet rock on the laundry room side; the kind made for moist areas. Notice I still recommend the rock wool insulation because this is a good application for it.

And I have never heard of styrofoam sheets as a sound proofer. Perhaps the spray on product would work, I don't know about that, but I do know it would be more expensive than rock wool and rock wool is specefically make for sound barriers.


----------



## ADHDan (Aug 17, 2012)

Thanks for all the suggestions, everyone. On reflection, I've had a change of heart - I think I'm just going to use free-standing cabinets/hutches and hang 5/8" drywall with resilient channels on both interior walls and the ceiling. I should be able to take down the shop-side drywall and just use it on the laundry-room side of that wall, meaning I'll just cut a new set of 5/8" drywall to hang with the RCs on the shop-side wall.

For insulation, I spoke with a professional woodworker friend who suggested using plain old styrofoam sheets between the studs, two 1" sheets per cavity with little spacers in between so that they don't touch each other or the drywall. Basically, he said to make alternating layers going: drywall-> air pocket-> styrofoam-> air pocket-> styrofoam-> air pocket-> drywall.

1" styrofoam isn't that exepensive at the Big Box stores, but it's not super cheap either. I can check around to see if I can get styrofoam sheeting as scrap from furniture places, but otherwise what would you recommend that's cheaper to use as a sheet insulator in the above "layered" configuration. Also, can someone post a link to the rockwood product referenced above? Again, this is my first venture into construction so please pardon my naiveté.

Thanks again!


----------



## Ripthorn (Mar 24, 2010)

The three basic rules of sound isolation are:

- Mass
- Airtightness
- Mechanically decoupled

So you want high mass, completely airtight, and mechanically decoupled whenever possible. What does this translate into? The more drywall you can hang on the wall the better, completely fill in any and all gaps, as even the slightest gap will transmit more sound than you would think, and don't use the same studs for the drywall on both sides of a wall. You will get far superior performance putting in a second wall frame that is separated by 1/2" from the other. Also make sure you get the heaviest door you can find, as those are a very typical weak link in sound isolation. I spent several years doing architectural acoustics and such, and doors and windows will make all of your other investments virtually worthless. With how expensive RC is, I would use that on the ceiling only and double frame the walls. You'll get better sound transmission characteristics that way.


----------



## ADHDan (Aug 17, 2012)

Can I rough in 2×6s in between the 2×4 in the existing wall frames to get a staggered stud effect?


----------



## Lynden (Oct 13, 2009)

http://www.roxul.com/files/RX-NA_EN/pdf/SnS%20Sheet_Eng.pdf


----------



## Ripthorn (Mar 24, 2010)

You could do that as long as your new "base plate" is not touching the previous one, which can be handled by planing 1/4" or so off the firring strip. Materials like quietrock, roxul, dead sheet, etc. are decent, but very expensive. In my guitar room I have two layers of 5/8 fire code dry wall and the sound reduction is through the roof (pun intended). If you do multiple layers, make sure to not have any overlapping seams.


----------



## rockrunner (May 10, 2012)

Check out Quietrock.com. 1 sheet = 8 sheets great stuff I install it all the time. Works as long as you use the whole system .


----------



## Woodbum (Jan 3, 2010)

Make a double staggered fire/sound wall like used in apartments or commercial office spaces. I used fiberglass insulation and 4×8 sheets of styrofoam glued to the studs under the drywall. This helps mitigate sound transfer through solid materials. For support, use blocking nailers between the studs set at selected heights for maximum weight support. I would not use anything less than 3/4" plywood for the walls in the other application choice to support heavier weights. Use the staggered wall with fiberglass and styro here too. It is very hard to soundproof living spaces right next to a howling joiner, planer, compressor or most woodworking tools for that matter. Good luck, work safely and have fun.


----------



## ADHDan (Aug 17, 2012)

Thanks for the replies. A lot of the best suggestions simply aren't feasible for me, but after reading all the replies and doing a little research I think I have a pretty good cost-effective plan. I'm going to put in two layers of styrofoam with spacers to make alternating layers of air and styrofoam in each stud cavity. Then, I'm going to run a strip of window sill insulation (1/4" foam, similar to floor underlayment) down each stud before attaching drywall, and finish with two layers of drywall (alternated to avoid overlapping seams). I can do all of this for under $200, which is squarely in my price range.

I decided against using resilient channels because, honestly, I think I'll probably screw up somewhere and short circuit them. They are kind of expensive and look pretty hard to install.

Anyone have major concerns, or see anything that could be better while still in the $200 price range? Thanks again!


----------



## LakeLover (Feb 2, 2013)

RC is easy as heck and not expensive. I buy mine at a Drywall supply.

Look at Green Glue. It is a highly rated product.


----------



## ADHDan (Aug 17, 2012)

I keep going back and forth on the RC, but at this point I think that being able to hang cabinets may be a priority since my shop is pretty small. I am looking at Green Glue, though.


----------



## Ripthorn (Mar 24, 2010)

RC gives its biggest bang for the buck on the ceiling. Ceilings are notoriously difficult to deal with.


----------



## ADHDan (Aug 17, 2012)

Yeah I'll most likely use RC for the ceilings.


----------

