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Looking for suggestions on how to level floor

mrjjw007 | Posted in Construction Techniques on October 10, 2011 10:59am

I have 20 year old prefab home. Main floor was produced in two halves and assembled on site. It is sitting on columns in basement and the two halves are bolted together  

One half of the floor is perfectly level while the other is not – see attached pictures. Previous flooring was thick carpeting and now I am considering vinyl. The hump was pronounced with carpeting and I am expecting vinyl will do nothing more to hide it and that it will only seem to get bigger.

I am looking for ideas to level. I was thinking about removing decking on high side and replacing with thinner plywood (bracing from crawl space) and using floor compound to bring to proper level??.

There may be chance to remove some shims from crawl space, but I am not sure.

The floor joist from basement look pretty level.

Any thoughts or suggestions would be appreciated!

Thanks,

 

John W.

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Replies

  1. TLE | Oct 10, 2011 03:31pm | #1

    Work from below

    Assuming it is accessible from underneath, drive the floor sheathing up to the desired level.

    Sister some cleats to the side of the joists, forced up to the bottom of the sheathing. Use construction adhesive liberally.

     

    I have had good luck just using floor leveling compound and feather it out to disguise the problem - depends on your abilities.

    My best advice - friends don't let friends buy modulars.

    Terry

    1. mrjjw007 | Oct 10, 2011 04:50pm | #6

      thanks X 3

      Thanks for being persistent and getting this posted. It is accessible from crawl space, so I am sure I could get sawzall to remove nails and liquid nails and then introduce sisters...........(not sure how flexable the osb will be???) but then I would have two halves sloping up and then 3” level portion where the filler strip goes…..may be the floor leveling compound feathured out couple of feet is the best way to approach this.

      Thanks for your input.

      JW

      1. calvin | Oct 10, 2011 05:16pm | #7

        Is the crown at the joint between the two halves?

        Can you lower that joint so it flattens out?  If a beam with shims, take up the weight and remove shims.

        Of course, you don't want to lower it too much, you'll risk cracks above.

        How much crown is there?  That picture with a level doesn't show much.

        You mentioned one side level, does that mean the other half isn't?  or are they both high in the middle?

        1. mrjjw007 | Oct 10, 2011 07:35pm | #8

          The difference between high side and low side is 1/4" to 1/2"

          The joist in basement do not have much crown and I did not check out crown on decking since carpet is still on.

          I might be able to remove 2 x shim and kiss with planer to take some off???

          1. calvin | Oct 10, 2011 07:41pm | #9

            Just a little clarification.............

            Are you saying FROM one side of that space to the other there is a 1/4 to 1/2" difference in the height of the osb?

          2. mrjjw007 | Oct 13, 2011 10:16am | #11

            Yes the difference in height between one preassembled panel and the other preassembled panel is up to 1/2". That filler strip spandes from high to low............

          3. calvin | Oct 13, 2011 06:27pm | #12

            If that's the case............

            is it possible to redo the joint?  Unbolt it and redo the lining up?

            If not, and you can remove enough sheeting, you might be able to gradually bring up the low to high with sisters on the side of the joists.  When resheeting, span a full sheet across that joint-2' each side, then fill in to what you removed. 

            You'll still have a hump, but it'll be gradual.

            When things are off that much, there isn't a real easy fix available to you.  Redo or hack and whack to make it go away or be less noticeable.

            Best of luck.

  2. TLE | Oct 10, 2011 04:07pm | #2

    Work from below

    Assuming it is accessible from underneath, drive the floor sheathing up to the desired level.

    Sister some cleats to the side of the joists, forced up to the bottom of the sheathing. Use construction adhesive liberally.

     

    I have had good luck just using floor leveling compound and feather it out to disguise the problem - depends on your abilities.

    My best advice - friends don't let friends buy modulars.

    Terry

  3. TLE | Oct 10, 2011 04:08pm | #3

    Work from below

    Assuming it is accessible from underneath, drive the floor sheathing up to the desired level.

    Sister some cleats to the side of the joists, forced up to the bottom of the sheathing. Use construction adhesive liberally.

     

    I have had good luck just using floor leveling compound and feather it out to disguise the problem - depends on your abilities.

    My best advice - friends don't let friends buy modulars.

    Terry

    1. TLE | Oct 10, 2011 04:11pm | #4

      Goddamn Mollum made me enter it three times and posted it three times

      Terry

      1. calvin | Oct 10, 2011 04:14pm | #5

        Terry

        They've made it easy for you to have mollum's captcha requirement removed.

        There's a thread with a title like that-from Gina.  You just include your name and poof, it's gone.

        Best of luck.

        1. DanH | Oct 10, 2011 08:25pm | #10

          Yeah, right.

  4. mattinhalifax | Oct 20, 2011 03:06pm | #13

    What about 3/8 plywood on the low side? 

  5. IdahoDon | Oct 21, 2011 10:00pm | #14

    I would want to know what the entire floor is doing...what is level and what isn't, and adjust the actual floor if possible and it sounds like it is.   Of course if the floor is solidly settled into the foundation there isn't anything wrong with leveling compound if done right.  Messing with the floor might be a no win situation since any adjusting will settle over time and the joing doesn't sound like it will ever be exactly stationary at the joint.

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