Replies

1. 
   BG | Oct 10, 2002 05:22pm | #1

   Badoyn,

   Both of those might help and maybe even the foam option.  However, I would check with with someone who knows about sound...there is a whole world of products that may do the job better and more cheaply.  Also, In many localalities, taxes go up if they find out you have put a ceiling in your basement..should check that issue also.

1. 
   badoyn | Oct 10, 2002 05:30pm | #2

   I think I'll refrain from the foam issue because I would like the option of removing the insulation when I replace the sub-floor and hardwood above (future project).

   Also, I'm not putting in a ceiling per se, just some sound deadening. I'm not finishing the basement.

   Thanks for the info,

   Michael

1. 
   ian | Oct 10, 2002 05:43pm | #3

   Michael

   You're in for some fun.  Whilst I don't pretend to be a sound engineer, I think you'll find that to achieve a worthwhile reduction in sound transmission out of your basement you'll have to put in a ceiling. 

   In general, preventing sound transmission requires a combination of sound reflection and sound absorption.   Reflecting the sound would mean the sound waves bounced arround inside your basement till thay ran out of energy, so you'll probably need some absorption material across the entire ceiling.  If you don't, sound will likely transmit to the spaces above via the joists.  The amount may or may not be a problem.  Putting sound absorbing material on the walls may also help.  A lot of concert halls have curtains in front of the walls to cut down on sound reflections.

   ian

2. 
   MWQuick | Oct 12, 2002 02:36am | #4

   As a former sound engineer and a current general contractor I can tell you that the only way to stop sound transmission is with mass. Meaning the more mass you have between the floor levels the less sound will transmit through it.

   Most power tools operate (under load) at around 130 decibels, about the same level as a jet airplane. But, because power tools operate at a higher frequency the sound waves are shorter and thus require less mass to stop them from getting through  to the other floors.

   Insulation, padding, carpet sometimes muffle the sound enough to solve the problem in certain situations. Usually, it's not enough to reduce the sound level effectively. I would install R-19 insulation between the floor joists ($.40 per sq ft) and 5/8" sheetrock ($.25 per sq ft).  If the sound levels upstairs are really bad you can install another layer of sheetrock.

   You could do all of this yourself in about a days time with a helper. I'm not sure what the local building codes in your area are, but because you're not creating a "livable space" you should have no problem with the inspectors.

   Hope this helps

   Monty

1. 
   badoyn | Oct 12, 2002 06:30am | #5

   Thanks for the info.

   Would the insulation better block the sound if it was the "fluffy" type or the ridgid type?

   Thanks,

   Michael

1. 
   riverr1 | Oct 12, 2002 07:16am | #6

   If you use drywall I would suggest hat or RC1 channel which will attenuate noise even more then the insulation, according to the manufacturers anyway. It creates a minimal cross section between you ceiling joist and the drywall was the vibrations, which is noise, doesn't transfer from the drywall to the joists, to the floor, walls, ceiling, etc. Check out USG.com. Lots of info on sound proofing.

   Don

1. 
   krislu | Oct 12, 2002 02:06pm | #7

   Check out a company called sound coat. I got some sound foam from them that works awesome ! I have a garage shop and everytime my compressor turned on I wanted to jump through the window. Anyone in the house could hear it too, until I put some foam around the compressor and it cut the sound in the garage in half and eliminated the sound in the house.  Good luck  - Kris

2. 
   wop | Oct 12, 2002 04:21pm | #8

       Fluffy type or also called open pore absorbes high and mid frequency. For low frequency a thin sheet of lead is necessary best between two sheets of open pore insulation . On auditoriums, theaters and such we use this system,a premade product produced here in Italy , sort of sandwich that comes in rolls. Expensive but effective.

                                                             Philip Allen

                                                        Architect,Designer

3. 
   MWQuick | Oct 12, 2002 10:54pm | #9

   Use fiberglass insulation and it doesn't need to be kraft-faced. I don't know what size your floor joists are but for sound control, the more you can pack in there, the better.

   Just a note. These are simple, low-cost solutions to your problem. There are specialty products out there designed specifically for sound control if you'd like to spend the money for them. But as I understand you, you simply want to REDUCE the sound levels to the other floors.

   For some reason, I'm not able to read anything on this thread AFTER my first post and I'm not sure if I mentioned this but you can double up the sheetrock if you need to reduce the sound further.

1. 
   badoyn | Oct 13, 2002 12:30am | #10

   Thanks. I'm just looking for a quick, low-cost solution to reduce the sound to a more manageable level.

   Michael

3. 
   RW | Oct 13, 2002 02:43am | #11

   I only have one thought but it could be entertaining. I had a good friend back in college who was a drummer. He found some panels whick look like drop in tiles for a grid ceiling but he said were designed to reduce sound. I guess you'd say they were sound attenuation panels. He lined the walls and ceiling of his practice room in the basement with them and they were remarkably effective. Couldn't be that difficult to locate, should it?

1. 
   RSRose | Oct 13, 2002 02:59am | #12

   RW,

   I think you're describing acoustic ceiling tiles. They're pretty good in absorbing sound in a room or an office. They make for a nice quiet work environment.

   Y'know those acoustic tiles have to be flushed out every so often - they can only hold so much noise.

   We have them in all the rooms in the office building I work in. One night I came in late while the cleaning crew was in. They were flushing out the ceilings in several rooms. Man, what a racket that made 'till they got them all cleaned out!

   Rich

   Edited 10/12/2002 7:59:46 PM ET by Rich Rose

1. 
   DennisS | Oct 13, 2002 04:08am | #13

   You have to have special OSHA approved bags to put that stuff in when you flush the tiles, too, Rich. Any leaks/holes and you end up contributing to the noise polution in the streets!!!

   All seriousness aside, there are only two things that effectively block noise from passing from one space to another: blockage of air passages and mass. Mass is most effective when dampening low frequency noises. Low frequencies tend to create sympathetic vibrations in partitions that produce, albeit at a lower volume level, noise in the adjacent space. Higher frequencies with shorter wave lenghts can travel through air passages from one space to another.

   Acoustic panels applied to the surface of a wall are effective over a general sound spectrum but for the high pitched whine of a router or the low rumble of some of the other machines I don't personally think they'd be too effective. They work best to reduce reflected sound images than they do for reducing transmited sound. They're pretty porous. Even concrete block left unsealed will transmit certain frequencies since it's not impervious to air infiltration.

   One approach which may be beyond the measures the original poster is willing to go would be to hang another layer of 5/8" drywall on the ceiling of the shop furred down with resilient furring channels. The mass would absorb a great deal of the low frequency sound and the resilient channels would lessen the transfer of sound through the floor. A good taping job and use of surface mounted rather than recessed lighting (which would compromise the integrity of the ceiling) would reduce the higher frequency transmission.

   All that said, if there are any paths of travel between the shop and the rest of the house, nothing done *in the shop* will be of much benefit - the sound will travel through the door(s) up the stairs and throughout the rest of the house.

   Incidentally, these are design critera from an acoustic consultant we've used for many years in the building design profession.

   Dennis in Bellevue WA

   [email protected]

   Edited 10/12/2002 9:17:24 PM ET by DENNIS02

1. 
   RSRose | Oct 13, 2002 05:29am | #14

   Dennis,

   A number of years ago, my wife and I had an accountancy business and our offices were located in a light-industrial park. Our space was separated from the next "bay" on either side of us by nothing but the thin, corrugated steel skin of the building. You probably can picture the typical, 2-story, block-long warehouse type structure populated by many diverse businesses. A printing shop, a plumbing outlet, carpet warehouse, travel agency, and like that.

   On one side of us was a store-n-lock business. On the other side was a paint store. I never gave a thought to the fact that our offices were pretty quiet. Every once in a while, we heard a faint noise through one wall or the other, nothing to speak of.

   Then an auto body and paint outfit moved in next store. Suddenly there was the deafening howl of impact wrenches, grinders, saws, metal tools being thrown on the floor. The metal structure of the building transmitted every sound into our space as though there was nothing between us and the machinery. Worse, they played a sound system at volume levels above their machinery 16 hours a day, non-stop.

   We couldn't operate our business. We couldn't sit at our computers, talk to customers, nothing. The landlord refused to do anything nor let us out of our lease until we brought a lawsuit.

   Eventually the landlord promised to "sound proof" the autobody shop. I didn't believe that it could effectively be done. My nerves were shot from the constant noise and lost business time. Since only a thin steel membrane separated us, I predicted that sound proofing would fail. Especially when they showed me the sound absorbing material. It was no more than an inch thick. It was quite heavy, but it did not have a lead lining.

   The auto shop had to shut down while the installation was done. So the noise was suddenly stopped. We started to get caught up on work with the blessed quiet. What a relief! About 2 weeks after they started, one of the insulation installers came into our place and asked how we liked the quiet. I told him it was great, but that I dreaded the auto shop starting up operation again. He said, "They've been in full operation since yesterday." There was not a sound coming through the wall. I looked at him, dumbfounded. I refused to believe him. He invited me next door.

   When we walked through their door, the noise was deafening. From that time on, we never heard a thing unless one of their guys accidently hit a building strut with a metal tool. Even the sound of tools thrown on the concrete floor didn't come through.

   I don't know what they used, but those installation installers sure knew their business.

   Rich

2. 
   BG | Oct 13, 2002 01:08pm | #15

   Rich,

   We all know you live on an island that dosen't have electricity yet...and that your TS is a flat rock with seashells attached to the edges.  You don't work in a multistory office building...that is a tree house.  Your doing some nice work with those coconut shells, keep it up... 

1. 
   RSRose | Oct 13, 2002 08:02pm | #16

   BG,

   Nuts! Busted again!

   Gotta go now and check out a change I made to my TS. It's a power version now. I hooked up a goat as the power source. The goat walks round and round eating grass while tethered to a rotating pole. I'm using vines as a belt between the pole and the saw arbor (a tree branch). What an improvement over the foot treadle!

   Rich

   Edited 10/13/2002 1:08:31 PM ET by Rich Rose