Adelie 5 #1 Posted February 8, 2023 Hi, I'm new here. I have a question for those with construction knowledge. I've got a three story house I am renovating from gut level. It will be three separate units, each unit will occupy one floor. I'm thinking of placing used rubber conveyor rolls as a floor underlayment to reduce noise. Each unit will have wood flooring, no carpet. Does this seem like it would work? There is a lot of used rubber conveyor rolls nearby. I'd really like to dampen the foot traffic to make the whole building more hospitable. I've looked into actual sound proof underlayment options. While those would probably work, it is hard to come by the square footage I need without buying new. To boot, this option is quite costly. Remnants of this type of sound proof underlayment I've found in small pieces as most people just soundproof one room, not a whole house. This building is in Pittsburgh, PA, where the rain, snow, salt and general dirt make carpet and its padding a gross option that I'm not willing to consider. I like going with already used building materials to reduce my consumer guilt. It takes a lot of stuff to get a building habitable. I thank you and appreciate any feedback. I chose to post this here as in 2019 a member inquired about using rubber conveyor rolls in his shed. -Adelie 1 Share this post Link to post Share on other sites
Racinbob 11,075 #2 Posted February 8, 2023 I would think sound batts in the joists would be better. If nothing more what about a fire? 2 Share this post Link to post Share on other sites
ri702bill 8,318 #3 Posted February 8, 2023 (edited) 8 minutes ago, Racinbob said: I would think sound batts in the joists would be better. If nothing more what about a fire? You need to talk to the area building inspector before doing this - what you suggest MAY work, but may also be quite illegal... I live about a half a mile from the infamous Station Fire site - that had exposed flammable sound deadening foam that caught fire - 100 dead, 200 injured, 100 survivors whose lives changed forever... Edited February 8, 2023 by ri702bill 1 2 Share this post Link to post Share on other sites
Blasterdad 2,692 #4 Posted February 8, 2023 That was my first thought when reading your post. Rubber is TOXIC when it burns & almost impossible to put out. There is no way it would pass code, more than likely illegal even. You could end up being criminally liable. 3 Share this post Link to post Share on other sites
ri702bill 8,318 #5 Posted February 8, 2023 3 minutes ago, Blasterdad said: That was my first thought when reading your post. Rubber is TOXIC when it burns & almost impossible to put out. There is no way it would pass code, more than likely illegal even. You could end up being criminally liable. That pretty much says it all - look for an approved material - fiberglass batts perhaps ?? 1 Share this post Link to post Share on other sites
Adelie 5 #6 Posted February 8, 2023 Thank you, thank you and thank you! I'll keep looking for an alternative. 2 Share this post Link to post Share on other sites
Pullstart 62,849 #7 Posted February 8, 2023 Your profile says your favorite model is an RJ-25. Do you have one? Any ? 2 Share this post Link to post Share on other sites
Racinbob 11,075 #8 Posted February 8, 2023 (edited) 1 hour ago, ri702bill said: You need to talk to the area building inspector before doing this - what you suggest MAY work, but may also be quite illegal... I live about a half a mile from the infamous Station Fire site - that had exposed flammable sound deadening foam that caught fire - 100 dead, 200 injured, 100 survivors whose lives changed forever... Absolutely nothing like the batts I'm referring to. No foam at all and more fire resistant than fiberglass batts. They are designed and approved for an application such as this. Not only for sound but for increasing the fire resistance as well. Win, win. Edited February 8, 2023 by Racinbob 2 Share this post Link to post Share on other sites
ri702bill 8,318 #9 Posted February 8, 2023 Ah, but the cost... That was part of the Station fire fiasco - club owners used a cheaper toxic flammable packing foam instead of what they were quoted... 1 Share this post Link to post Share on other sites
Racinbob 11,075 #10 Posted February 8, 2023 3 minutes ago, ri702bill said: Ah, but the cost... That was part of the Station fire fiasco - club owners used a cheaper toxic flammable packing foam instead of what they were quoted... I'm thinking somebody was in a massive amount of trouble. I don't know of any type of foam, spray or otherwise, that doesn't require a fire barrier. This house uses what's called an 'Ice Block' basement wall. A steel structure encapsulated with foam. There was no fire barrier at all. I have no clue how they got a CO when it was built. Well, I do but I won't go there. The sellers were having a hard time selling it saying it was because everyone wanted a finished basement. I knew that was 100% BS. Even a home inspector with their worthless inspections would catch the dangerous situation that existed. If there would have been a fire down there you wouldn't have had to worry about getting out. The fumes would have killed you before the fire did and you likely wouldn't have made it to the door. The minute we moved in I hauled some 70 sheets of drywall and got to covering it up. Nothing else mattered until that was done. Again @Adelie check out the sound batts I'm referring. They are often even specified for fire walls in apartments. Don't cut corners there. 2 Share this post Link to post Share on other sites
lynnmor 7,305 #12 Posted February 9, 2023 Rethink the carpet option, it might be the best idea for renters that will destroy it under any circumstances. Buy the cheap stuff and plan on replacing it often and allow enough in the lease to pay for that. Put heavy plastic under the carpet to catch the spills that will happen, otherwise you will be replacing sub floor. Better yet, forget the landlord business, I did. 3 Share this post Link to post Share on other sites
953 nut 55,216 #13 Posted February 9, 2023 To reduce sound transmission I would suggest using rockwool batting. Also you can use 2 X 4 strapping running at a right angle to the joists on the bottom to hang the ceilings, this will reduce sound transmission quite a bit. A double layer of ceiling drywall will also cut down on sound transmission. 1 Share this post Link to post Share on other sites
Racinbob 11,075 #14 Posted February 9, 2023 (edited) That's exactly what I was referring to. Deadens sound and increases fire rating. ROCKWOOL SAFE 'n' SOUND Attic Wall 59.7-sq ft Unfaced Stone Wool Batt Insulation (15.25-in W x 47-in L) Individual Pack 1 total Piece in the Batt Insulation department at Lowes.com Edited February 9, 2023 by Racinbob 2 Share this post Link to post Share on other sites
JimSraj 429 #15 Posted February 9, 2023 You might also consider resilient metal channel on the bottom of the joists. Ceiling drywall gets fastened to it to minimize vibration path. Along with rock wool in the joist bays and sound deadening drywall this assembly should do the trick. 1 Share this post Link to post Share on other sites
Lee1977 6,658 #16 Posted February 11, 2023 On 2/9/2023 at 7:20 AM, 953 nut said: To reduce sound transmission I would suggest using rockwool batting. Also you can use 2 X 4 strapping running at a right angle to the joists on the bottom to hang the ceilings, this will reduce sound transmission quite a bit. A double layer of ceiling drywall will also cut down on sound transmission. You will most likely have to use 5/8" sheet rock on the ceiling anyway as a fire bearer between floors. I drew the last set of apartment plans over 20 years ago, not sure what the code requires now. Share this post Link to post Share on other sites
Adelie 5 #17 Posted February 12, 2023 (edited) Thank you for the feedback. In my sons's shed we used Havelock wool, https://havelockwool.com/fiberglass-insulation-vs-wool-insulation/ for insulation. It has proved to be quite the remarkable sound proof shed. I may go with that just for the ceilings. The problem here is the cost. I'll see how much money I can allow for this. I also found this professional sound reducer https://www.repurposedmaterialsinc.com/sound-abatement-foam/sound-abatement-foam-inventory-spreadsheet/. So maybe I will check out how much to do the two ceilings with this stuff? Ya, I'm in this building with too much money to back out now. I've got to finish and bide my time so maybe my children can have a solid investment. I definitely want to do the safe thing here, I plan on passing this on to my children-without passing on a nightmare. I appreciate all of your attention on my issue. It has definitely helped me flesh this out and move towards a suitable direction. I'm going to use the resilient metal channels on the joists to help as well. Thank you all so much. Adelie Oh, also, I grew up with a neighbor that had a rj-25. Best.Toy.Ever. Long after we all went our separate ways, I still returned to ride that thing when they had moved on. Edited February 12, 2023 by Adelie forgot to add an answer 2 Share this post Link to post Share on other sites