[wizard]

I was at work last nite when i realized something, drywall can really cut fown noise transmission. In this case we are talking commercial grade drywall that was installed to make a fire rated wall. This particular wall was built up to be several inches thick. One layer was a drywall like board probably a bit over an inch thick with a green colored facing material. Then there was some metal spacers and three layers of more conventional drywall but this stuff was much thicker, im guessing about 1" thick. While the wall was built for the insurance company to satisfy fire safety concerns the construction did kill a lot of noise from the area.

Im not really involved in commercial building construction so I'm not sure where the materials are purchased. Ive never seen such materials in home centers, or common hardware stores. So you might have too look around a bit. The same green faced boards where also used to line transformer vaults and the larger switch gear rooms.

The boards by the way are very heavy as you might imagine. In any event the idea comes to mind that several layers of 5/8" drywall would likely kill sound as effectively. Document the use of fire rated materials and it might even save you some insurance money. The nice thing here is that dryway is relatively cheap, readily available and easy to work with. Drywall of course sucks in manufacturing areas due to the ease of punching through the thin stuff but that would be less of a problem when built up with 2-3 layers of 5/8" panels. .

[wizard]

Unfortunately all of my spare cash flow right now goes into home repair. I had to put off somethings that i really shouldn't have thus im expecting to be cash poor for at least two more years. So the only guns i will have are the ones i already own.

As for air rifles yeah they have come a very long ways of late. Certainly not the toys of childhood anymore.

About the only "hunting" i do anymore is for pest control. My parents sold off the house in the country years ago, sadly just before my fathers death. I do miss that place as it was twelve acres in the middle of farm country. More so one large garage filled with tools to keep a kid occupied on his latest "invention". My interest in machines started very early in life to say the least.

No arguments from me about protecting my hearing. I have seen what machine noise did to my farther' hearing after working in factories for years. It's one of the reasons why sound-proofing is a priority. I think it is better than relying on wearing ear muffs all day. It's also more considerate to others who are close by.

BTW, if you like target shooting at home (like me) and you have sensitive hearing (also like me) then I highly recommend trying a quality PCP air rifle if you haven't already. Most of them have built in baffles these days so they are quiet enough to shoot without hearing protection. My Taipan Mutant (my main hunting rifle) is so quiet that my neighbor can't hear it even when he's in his garden. It will put 10 shots inside 1/2" at 50 yards too. Awesome for small game hunting.

[LeeWay]

When I was younger and worked as a Framing carpenter, we had to take over a job on an apartment complex where the last crew had been thrown out. Took quite some time to correct all the framing errors. Then we had to hang the fire walls between apartments. It was two layers of 5/8" fire rock on each side of the wall for a total of two hours burn time. This stuff did have fibers in it and it was not standard white gypsum mix. It was darker in color and much nastier to the respiratory system. Those 4 layers and the airgap in between made these walls virtually sound proof as well. They carried out sound testing before the job was passed. We used some really cool special fat fluted screws and special fire rated adhesive to bond everything together. No two seams could run along the one underneath.

[wizard]

When I was younger and worked as a Framing carpenter, we had to take over a job on an apartment complex where the last crew had been thrown out. Took quite some time to correct all the framing errors. Then we had to hang the fire walls between apartments. It was two layers of 5/8" fire rock on each side of the wall for a total of two hours burn time. This stuff did have fibers in it and it was not standard white gypsum mix. It was darker in color and much nastier to the respiratory system. Those 4 layers and the airgap in between made these walls virtually sound proof as well. They carried out sound testing before the job was passed. We used some really cool special fat fluted screws and special fire rated adhesive to bond everything together. No two seams could run along the one underneath.

I just wish i knew what they called the stuff. In the case i was looking at they had used two types of materials. One looked very much like drywall but a bit thicker. The other board was sheathed with a greenish tinted material that almost looked like a fabric. The cores looked a bit different too with one being almost identical to drywall.

I suspect a wall done this way would be the cheapest way to killing sound transmission.

[killersoundz]

As a recording studio guy I'm well versed on sound proofing. forget the insulation, that's sound dampening. sound proofing involves decoupling an interior wall from an exterior wall. You want to use staggered stud construction for the walls, some kind of floating floor, and come up with something for the ceiling. staggered studs leave no mechanical connection between interior and exterior walls this simple thing changes a wall from stc 30 to stc 60

[greenene]

I kind of concluded that a room in a room is the way to go, and if I keep it small, cost can be managed. Do you still suggest insulation and two sheetrock attached with green glue. Essentially, staggered studs, sound insulation from the box stores, sheet rock 1, green glue, sheet rock two. This, of course, applies to floor and ceiling.
tony

[65matt]

Hey guys, first post here, I'm a commercial contractor. 2 layers of drywall stops a LOT of sound. I once worked on a mall that had a Bose store in it. In the listening room, that's what they used, along with regular insulation in the wall.

You can buy acoustical sealant that would be good for sealing joints and cracks. You can buy the sealant and commercial drywall locally, just look up a drywall supply store near you.

Commercial drywall comes in lots of flavors now, paperless, fire rated, moisture resistant, and different thicknesses. 5/8" fire rated is probably the most common.

There is also an exterior sheathing board commonly called DensGlass. That stuff is stronger and waterproof. I think it has a mixture of gypsum and fiberglass in it.

[wizard]

I kind of concluded that a room in a room is the way to go, and if I keep it small, cost can be managed. Do you still suggest insulation and two sheetrock attached with green glue. Essentially, staggered studs, sound insulation from the box stores, sheet rock 1, green glue, sheet rock two. This, of course, applies to floor and ceiling.
tony

I wouldn't go overboard, two layers of drywall on each side of the studs ought to do it. You have to remember there is is a wide array of audible frequencies coming for the machine in operation. Most of those would either be reflected or adsorbed by the sheet rock.

Now if you are concerned that one set of studs won't be enough, do the inside walls first to get an idea as to how much the sound is deadened. If you have one use a sound meter to get an unbiased opinion. The sound meter will give you a better idea of what has been accomplished because your ears will adjust sensitivity, if you will, when in a quite room.

[jono5axe]

CARPET UNDERLAY!!!

Hi there. I did not read every post here but I did skim through and see that there was some good points. But, I did this exercise recently myself for some noisy plant so can give you some good info....

Firstly, consider that you have mainly higher frequency vibrations coming off the router, rather than low frequency (base, thumping vibrations). This is good because it is easier to get a result with higher frequencies, and more difficult for low frequencies.

Extra sheet-rock (or gypsum board) will have some effect, but only limited if not decoupled, as other posters have said. Sheet-rock is in itself not a good acoustic insulator, so just adding more is not a good solution. Decoupling is just a separation of the hard materials (wall studs, sheet-rock, framing, etc) to stop direct transmission of vibrations trough the wall. Most basic method can be done with a sheet of high density vinyl between framing and sheet-rock. This method decouples (partially) and also absorbs. But the vinyl is quite expensive. There are other products, for example non-woven polyester fibre mat, that come in 25mm, 50,, 75mm thick etc, but will get full of dust if not protected somehow, and also expensive. There is also standard building acoustic insulation (expanded rock? glass fibre?) that can be used in the framing cavities, which fairly cheap stuff.

But, now my solution. I used standard foam rubber carpet underlay which is 12mm thick. Cheap, and I can confirm that it works very well for the higher frequencies. I have used it triple thickness on a 700mm diameter ducting pipework system that sounded like a 747 taking off and it worked very well. I have done a particularly noisy spray booth by lining the plenum chamber, which was also effective. For that I sourced a used house lot, which was free. The biggest cost was if we used multiple layers we used a spray contact adhesive to glue them together. You want to get the heaviest / highest density underlay. For the spray booth plenum, it was in the form of curtain liners, being foam underlay and 100% wool carpet as the outer facing, for a fire retardation lining and also sound absorbtion.

So, maybe put a 12mm layer of underlay on the wall (or framing), then put the outer layer of sheet-rock on over the top. Decoupled, and absorbtion.

I hope this info is helpful.

Jono

[greenene]

Thanks for all the comments. Since my post, I've added two walls to a corner of my garage, creating an 8x10 room for my cnc router as wells as other machines that create dust and noise. By using 5/8" sheetrock and rockwool, DB sound level from a router cutting into wood has been reduced to appx 55 db outside the room. Ventilation is provided by two air baffles, an intake and an exhaust baffle. Inside the baffle there are strips of wood to block the sound from traveling linearly. Outside the room, over the exhaust baffle, I've installed a Merv 13 air filter. It's set up so that I can slide it out to check it and place a new one in seconds.
The idea is to use a dust collector with a 1 micron bag inside the room( I will still wear a respirator) while the less than 1 micron dust goes through the filter, thereby keeping my garage as clean as possible from the fine particulates.
Some of you may wonder about the wisdom of a room over the machine enclosure. My need is to monitor and be able to intervene as quickly as possible while the machine is cutting. The pieces are simply too small for me to walk away from the machine while it's cutting.
Besides, the comfort of knowing that I can make noise while containing dust from all the dust making machines was worth the extra money spent.
The bottom of the door is flush with the floor so that all my machines can be rolled into the room effortlessly. The table saw is a good example.
Mistakes were made. This is in part due to the fact that most local contractors know nothing about soundproofing, and coordinating their presence with the availability of material was a real challenge.
My decision was also based on the fact that generating mdf dust is messy and dangerours. Containing it in a small room is, in the long run, a better approach than filling the entire garage with it and then dealing with all the residual fine particles all over the place.

While this solution to soundproof and dust may not work for someone who needs a large space for the type of work he or she is performing, it's perfect for the niche type of small, fine work that I do.

Those of you who wonder how I will deal with heat and cold in such a small place, I bit the bullet and installed a mini split for the garage as well as insulating the garage.

It's costly, but at my age and state in life, I wanted something a bit more comfortable. I've spent far too many years freezing and sweating in my garage.

[greenene]

After one month of running my cnc router in my soundproofed room, I have to say that it was the right decision. First, it has eliminated noise concerns 100%. I can work anytime without worrying about my wife or neighbors hearing the machine. Second, it contains the dust so that keeping the rest of the garage dust free is a delight. Moreover, cleaning the dust in the small room as well as dust suction requires little effort and fairly inexpensive dust collectors.
I've also placed casters on the table saw and miter saw, so all the dust making machinery is used in the "soundroom" when I need to use that equipment.
The only problem which I didn't realize during construction is the sound reflection off the walls effect. My sound meter indicates an increase of 10db inside the room than when the machine is outside. the room. Normally, the db reading was in the 80's. Now it's in the 90's.
The sound simply bounces off the ceiling and the walls, thus creating sound amplification.
It should be fairly easy to tackle this problem with sound absorbtion blankets, tiles, or foam.
Again, as with anything having to do with sound, information and prices are all over the map. Almost all information pertains to musical related absorbion.
I don't want to do anything too elaborate or expensive. After all, I wear earmuffs.
Does anyone have any experience with cheap solutions?
thanks
tc

[jono5axe]

Like in the earlier post, cheap sound absorber solution is second-hand 1/2" foam carpet underlay. And/or pure wool carpet (fire retardant).

If you want a nicer/cleaner outside face it can be faced with foil faced 2mm thermal insulation foam, comes in rolls of various widths. Or vinyl.

All can be contact adhesived in place.

[wizard]

This is a great update, thanks for the details!


I might remind you to keep your dust collector in tip top shape. Wood dist in an enclosed space can be explosive.

Also 90db will lead to gearing loss so PPE is in order.

I have to wonder, did you take pictures of the construction?

After one month of running my cnc router in my soundproofed room, I have to say that it was the right decision. First, it has eliminated noise concerns 100%. I can work anytime without worrying about my wife or neighbors hearing the machine. Second, it contains the dust so that keeping the rest of the garage dust free is a delight. Moreover, cleaning the dust in the small room as well as dust suction requires little effort and fairly inexpensive dust collectors.
I've also placed casters on the table saw and miter saw, so all the dust making machinery is used in the "soundroom" when I need to use that equipment.
The only problem which I didn't realize during construction is the sound reflection off the walls effect. My sound meter indicates an increase of 10db inside the room than when the machine is outside. the room. Normally, the db reading was in the 80's. Now it's in the 90's.
The sound simply bounces off the ceiling and the walls, thus creating sound amplification.
It should be fairly easy to tackle this problem with sound absorbtion blankets, tiles, or foam.
Again, as with anything having to do with sound, information and prices are all over the map. Almost all information pertains to musical related absorbion.
I don't want to do anything too elaborate or expensive. After all, I wear earmuffs.
Does anyone have any experience with cheap solutions?
thanks
tc

[greenene]

I didn't take any construction pictures, but I am happy to say that the room was built with single walls, 3" rockwool insulation, and doubled up 5/8 sheet rock. For ventilation, we built two baffled openings on opposite sides of the room, one for input and the other for output. On the output( outside the wall), there's an air filter, Merv 7. The vent opening is only 3x16" wide and the sound passes through a maze of staggered boards inside the vent box. Think of it as a labyrinth for the sound to travel. I've installed 5 80mm 100 cfm fans to pull the air out and overcome the resistance of the filter. They are 12 v fans wired with two switches so that I've have a 2 or 5 fan combination.
The cnc router has a dedicated 600cfm dust extractor with a 1 micron dust bag.
The bottom line is that dust and noise are contained in the room, and the the rest of the garage is practically dust free, leaving me with the luxury to work on non dust making activities.
As to the sound rebounding issue, my test meter shows the frequency to be around 10000 hz, which is considered high frequency that can be absorbed easily with rockwool make panels, which is what I've decided to do, given the low cost and my being able to cover the insulation with a fabric that can be vacuumed easily as dust builds up.
When one considers the cost and complexity of having dedicated dust collection on each machine without necessarily addressing the noise, having machinery on casters and using the soundroom for the "dirty work" may be a good solution for some people.
Mind you, I am talking about those folks who are in noise sensitive neighborhoods or homes.
One more thing, the room gets warm easily, so I suspect that in the winter it will be very cost effective to heat.

[Phil_Par]

I added insulated wall around my steel table. It contained the dust for which I was very happy but reduction in noise was minimal compared to the amount of work it took to build the enclosure. My mistake: I used less than 1/8 thick white mdf paneling to seal the frame with Rockwool insulation. I think that having hard surfaces facing the inside of the enclosure make the sound rebound and it is not dissipated. I though about removing the inside hard cover (mdf paneling) and replacing it with a layer of carpet underlay as recommended below. I am hoping that this treatment allows the sound to get through the insulation and be absorbed as opposed to just bounds around. I am no expert so let me know what you guys think.

[arizonavideo]

I just made a mostly sound proof shop.

I will skip the walls for now but I added sound baffles made from both rock wool and the blue shredded cotton to make baffles like in the pictures above. I made them like picture frames with wire to hold the bats. 15" wide to fit the bats. Rock wool works well

Carpet helps too. I shop vac it to clean up the chips.

If you cover the bats with a fabric it will make them easier to clean.

[webmax]

Hello! Maybe someone will come in handy. I apologize that all the text in Russian but there and so everything is clear)

https://www.youtube.com/watch?v=Apc6Lctxn0A

https://www.youtube.com/watch?v=6TaWe9pvSlM

[peteeng]

Hi Greenene - For high freq you need something like old carpet of underlay but do not attach or glue it to the wall. It needs to hang just free of the wall so it can vibrate and decouple and dampen itself in air. Ideally when built the walls should not be parallel so the reflections do not echo back and forth. Cheers Peter

[klingeltonekostenlos]

I would love to choose your free music trick.