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Discussion Forum

How do I level and sound isolate a floor

NotaClue | Posted in General Discussion on December 20, 2004 08:40am

I am wondering if anyone has any ideas on the best way to level and sound isolate a 3rd floor (formerly attic) area that I want to use as a library/playroom.

The floor is above the sleeping rooms below and it wanders up and down through the level vertical plane by about 1.5 inches from the back to the front of the house—but not all in one direction or tilt (think waves and bowls, rather than tilting tables—not too surprising, it’s a 122 year old house–no misprint!)

Any ideas? Is there a floatable, lightweight, sound isolating solution wandering around out there?
Thanks!

Reply

Replies

  1. rez | Dec 21, 2004 10:22pm | #1

    A little more info supplied with this post so we'll run it thru again too.

     

     
    From:  Homeowner   Dec-18 6:41 am 
    To:  ALL  (1 of 2) 
      51592.1 

    With the range of experience on this site, what are the thoughts on how to spec the renovation of an attic (over bedroom living space) that currently as a functional but wavy and irregular floor, to
    1) Be level and
    2) be sound isolating?

    The total level about of out of vertical plumb is about 1.5 inches, but it varies from spot to spot (not a regular tilt); and it is an attic, with good structural bones (so the engineer/architect tells me) but couldn't take a floated concrete floor (at least, we don't THINK it could) in addition to everything else we want to put into it.

    Any ideas? that level the floor and sound isolate it so that people walking around on top with shoes on don't reverberate into the bed rooms below?
    Thanks!
    Notaclue

     
       Options  Reply  
       



    Edited 12/21/2004 4:49 pm ET by rez

    1. User avater
      Sphere | Dec 22, 2004 01:15am | #2

      good job there bump police man.I can only think of one thing that works and it disqualifys on the "lightweight issue.."sand. 

      Spheramid Enterprises Architectural Woodworks

      Repairs, Remodeling, Restorations. 

       

       

      1. zendo | Dec 22, 2004 02:11am | #3

        self level crete might work too, that would be pretty quick.

        1. zendo | Dec 22, 2004 02:18am | #4

          Homeowner,

          I dont think the age matters, it sounds like the house is underbuilt.  Older houses can have a droopy ceiling or 2 but that seems like the moon.  Plenty of old houses framework are as straight as they were 140 years ago. 

          Sounds like you are going to have to strap 16 on center, shim, and lay 3/4 inch ply to have a flat floor. 

          Or rip out the ceiling or floor and rejoist the place.

           

          what do you think, Sphere?

          Edited 12/21/2004 6:19 pm ET by zendo

          1. User avater
            Sphere | Dec 22, 2004 02:31am | #5

            he could do that..but my take is this...it ain't worth it. A PLAYROOM? ok, let's play marbles.An old house (mine included) will have waves and dips..in those floors that are overspanned and undersized..I just live with it.As soon as the word "light" entered into the "fix this" equation,I chose to not respond. When Rezster bumped it up I just added a thought from a previous hometheater I had built for a nut job..we layed 2" of sand on the deck and plyed over it. Crazy? probly..speced by an archy..you betcha.gyp crete is a way to go..but I bet the joists will groan no matter what ya apply. 

            Spheramid Enterprises Architectural Woodworks

            Repairs, Remodeling, Restorations. 

             

             

          2. zendo | Dec 22, 2004 02:41am | #6

            should just put down some indoor outdoor rug and drill a core in the floor and we could have a golf green. -- put up a net and add a fairway.

          3. User avater
            Sphere | Dec 22, 2004 02:49am | #7

            sand+half nekkid wimmins= BEACH VOLLEY BALL 

            Spheramid Enterprises Architectural Woodworks

            Repairs, Remodeling, Restorations. 

             

             

          4. NotaClue | Dec 22, 2004 03:59pm | #8

            Ah, yes, that would be wonderful (and perhaps appropriate here in California)...
            Sounds like I am in serious trouble if I want to get a level, sound isolated floor here, unless I am willing to pull up the current floor and then put down a new set of structural load carrying beams, spanning the entire width of the building...
            Hmmmm
            Any other ideas?
            Floating concrete...
            Respanning...
            Anything else???
            (I apologize, I just reposted on Rez's other reply to my first post on this same topic---didn't see the stream this had started to generate)
            Notaclue

          5. rez | Dec 22, 2004 04:20pm | #9

            It may serve you well to study old threads here at Breaktime to familarize yourself with what others have said about sagging floors.

            If you scroll down in the lower left corner of your screen there is a search function that will take you to previous threads dealing with whatever you type in the search bar.

            If you type in 'floor sag' or other keywords of the subject matter you'll get a good supply of data from those old threads.

            Cheers 

          6. User avater
            Sphere | Dec 22, 2004 07:58pm | #10

            actually..you could lay down "grounds" shims of the required thickness to find a level plane (string lines or laser is called for) and screed the sand to the level now established.cover with a subfloor of choice and screw into the grounds and or the existing joists.play room? vinyl and area rugs is the best approach, replace rugs when they get too mucked up. 

            Spheramid Enterprises Architectural Woodworks

            Repairs, Remodeling, Restorations. 

             

             

          7. zendo | Dec 22, 2004 08:55pm | #11

            I guess it was just he, you, and I that thought about this all night. lol

            I want to raise it 2 inch plus the scribe, and float rigid foam, but then we would probably have to go to the moisture problem thread.  Maybe loose foam poured like peanuts or those pellets in a bean bag between the 'new' overlay joists then sub floor. Or just plain blown insulation.

            yer killin me over here.

          8. User avater
            SamT | Dec 22, 2004 09:32pm | #12

            Set level screeds around all walls and partitions about 1"-1 1/2" above the highest point of the existing floor.

            Then, spray insul foam to a height above the screeds.

            Then, make an Alaskan Mill type device with a HD 'cup' wire brush to ride on the screeds.

            Then, mill the foam level,

            Then, glue and screw 1/2" ply.

            Then, pay the second mortgage?

            Where there's a bank account, there's a way.

            SamT

          9. NotaClue | Dec 23, 2004 05:26am | #13

            Oh boy; I'm laughing when I'm not crying....
            OK, maybe the only way to get from here to there is to pull up and reinforce the entire floor!
            How exciting! Time to buy my contractor another sailboat!
            However, I am learning something from all the feedback, so if anyone has any other ideas, please let me know!
            Notaclue

          10. pm22 | Dec 23, 2004 07:21am | #14

            Actually the foam idea is pretty good. I once did some work in the Deli-Mex plant and the floor of the attic was just panels of the stuff [SIPs?] -- solid foam sandwiched between a couple of plies of foil. We could walk on it [about 6" thick].

            Then glue on two layers of staggers 1/2" plywood.

            Then a layer of bubble wrap. Then a layer of 1/16" lead sheet [to absorb to low notes?]. Then the shag carpet.

            ~Peter

            Martha's roommate wants all of the above ASAP.

          11. NotaClue | Dec 23, 2004 08:07am | #15

            In all seriousness: which type of foam? closed cell non-expanding? or something else?
            notaclue

          12. pm22 | Dec 23, 2004 08:33am | #16

            I really don't know. Closed cell sounds good but somebody else brought up the idea. You want something stiff. Perhaps somebody else can add in.

            By the way, the lead foil and bubble wrap was hyperboyle. [In honor of Boyle's law]

            ~Peter

          13. zendo | Dec 23, 2004 06:23pm | #18

            I want some others to verify if a moisture barrier (Rigid foam) there will mess the house up or not, but I would use the blue or foil insulation foam.... problem is that if its directly contact to old and new floor it might squeak? thats why I suggested floating it between some strap type system, you could pressure fit it between 'joists'.  Both cut easy with circ trim saw.

            If people here say that moisture may be an issue, loose foam or insulation might be your answer.

            edit: Oh looking back now Im not sure which type of foam you like.(rigid or spray) lol

            Edited 12/23/2004 10:28 am ET by zendo

          14. User avater
            Sphere | Dec 23, 2004 07:00pm | #19

            yup...ridgid EXP will squeak..big time. styrofoam peanuts is an option ( man I am hooked on these things lately..LOL) no, the wheat? based ones are more better..keep em dry tho'...otherwise they disappear completly. 

            Spheramid Enterprises Architectural Woodworks

            Repairs, Remodeling, Restorations. 

             

             

          15. catmandale | Dec 25, 2004 07:40am | #20

            I vote for carpet, unless you want a resilient surface,  then you could consider cork tiles.

            Cork is generaly sold as a laminated glueless product, but can also be found as 12 x 12 or 12 x 24" tiles. They are usually adhered with water based contact cement.

            I would not worry about the uneven surface. It is a sign of character.

            Dale

          16. NotaClue | Dec 25, 2004 09:44am | #21

            Hey, the Cork was an interesting idea.
            Can I cork the floor then lay another wood floor sandwich over it? (I mean, structurally, will this work OK?)
            Thanks!
            notaclue

          17. catmandale | Dec 26, 2004 06:01am | #22

            Sure, and if you are going to "sandwich" it, you can use a lower grade of cork and save money.

            As a finished floor, the cork runs $1.75 - $6.00 psf depending on color and pattern. Bought as an underlayment, the price drops.

            Dale

          18. NotaClue | Dec 26, 2004 07:18am | #23

            This cork idea, you might have done it.
            Can anyone comment on the pros and cons of using cork versus using the specialist (and rather expensive, not to mention heavy) acoustic isolating vinyl tiles?I guess the products I am thinking about are:
            1) 3M marine acoustical insulation (http://products3.3m.com/catalog/us/en001/auto_marine_aero/marine/node_B7BP564W6Hbe/root_GST1T4S9TCgv/vroot_GS4JK4Y166ge/gvel_K6B2TWB8MXgl/theme_us_marine_3_0/command_AbcPageHandler/output_html)2) Specialized stuff, like the very expensive Glacier Bay acoustic matting, usually used for silencing marine engines (http://www.glacierbay.com/insulation_ultradb.asp)3) Engineered solutions, like Quietrock, Quietwood and the accompanying underlayment (http://www.quietsolution.com/construction___building.html?Google)Thanks!
            notaclue

          19. User avater
            SamT | Dec 23, 2004 06:18pm | #17

            Don't laugh at me!!!!!!!!!!!!!!!!!!

            Cerealously, If you do the 'shaving' yourself it won't cost that much. Some thought before starting anything, For the mill, 2 @ 6" or 8" steel studs, "block" them at each end and one place not in the exact center. Long enough to reach the widest area, cut shorter for each subsequent area. Flip 'em to "mill" the zone where the non-centered block is, or move the block. If any zone is too wide, place a "screed" (Yeah, I know that's not the right word) in the field. The cup style wire brush seems to be the best for 'milling' foam.

            Talk to the spray foam insulation contractor. I'll bet that whatever he's using will be stiff enough. The 1/2 ply will spread the force plenty good enough. Mostly it's the force of furniture legs ya' gotta worry 'bout. For that matter, go down to your local big box, walk on their selection and glue down panels of the stuff. Plan it right and you can save money by buying different thicknesses as needed.

            Every kind of foam I've dealt with, except that new fangled soft window and door foam from Great Stuff, has been stiff enough. Uh,. . . and seat cushion foam too. Although the seat foam in some of the resturaunts I've been in. . . .

            SamT

            Edited 12/23/2004 10:22 am ET by SamT

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