How would you fix this? Subfloor/Wall

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Posts: 15
Joined: Wed Aug 06, 2014 9:51 am

Hi All-

I thought I would make a new post on my drama. :(
While replacing my rotten floors it is becoming clear that unfortunately I will need to replace the particle board underneath the Wall studs. The Particle board is soaking wet, and does not see to dry thus it must be replaced. But how is the best way?

What I have: (this will be elementary for most here)
1. 2x6 Floor joist
2. 3/4" particle board
3. I didn't measure, but it appears to be a 1/2" pine sill plate
4. Finally, 2x6 wall stud on top of everything.

Idea 1. Take Sawsall and cut out particle board between joist and sill plate in 2ft sections, then Pound a strip of 3/4 plywood beneath it. (go stud to stud, and then sister in a 2x6 floor joist to carry the next 2ft. strip.

Idea 2. Take Sawsall and cut particle board and sill plate pine, then run a 2x4 underneath stud. However, in the picture below, I took a scrap piece of 2x4 and placed it on the joist. It does not looked tall enough, and appears to be 1/16" - 1/8" to short to carry the wall stud.

Those are my 2 ideas, someone got any better?



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Posts: 5696
Joined: Wed Feb 28, 2007 8:01 pm
Location: Weedsport, NY

If you read through the posts on this, I don't think there is any "best" method. I would go with whatever works for you. Some have managed to slightly lift the wall and gain a little work room that way. Remember, if it looks bad change it now. Do it once, and do it right.

"If I can't fix it, I can screw it up so bad no one else can either."
Posts: 622
Joined: Tue Nov 11, 2008 6:12 pm
Location: wisconsin

Like Greg said different ways work in different situations. First, you said it's still wet. Where is this water or moisture coming from? Get some fans in there or a dehumidifier and try to get everything dried out. Then try to treat the mold. These would be my first steps and will give you a better idea of the extent of damage. Without being there and just from your pictures I think I would try to raise the wall a little to cut out the old sill and slide new in. One way to do this would be to get a 4x4 and run it perpendicular to the floor joists about a foot from the wall. Then use a long pry bar to raise the wall using the 4x4 as a fulcrum. Do it in sort sections like you stated. The first section probably will be the hardest. Then keep moving down. Maybe use some extra 1/4" thick shims as you go to hold the wall up a little higher until you get the next section in, then take the shim out and move it down a section. Another option is to nail a 2x6 to the wall studs and then use a floor jack braced on the floor joists to raise the wall. Lots of options depending on the particular situation. Anyway you look at it it will be a project. So take your time and like Greg said do it right and do it once. Good Luck.
Posts: 79
Joined: Sat Jan 01, 2011 11:25 pm
Location: Huntsville, Alabama

1. Open the outside of the mobile home. Panels have very sharp careful. This will give you a chance to determine if any damage exists to your rim joists.
2. Run saws-all horizontally between bottom of sill and top of flooring. Go about 8' 2" at a time. If working an outside corner of the home, you'll have to remove bad flooring from underneath sill in both directions in order to be able to insert new flooring. Remove any staples/nails protruding beneath sill board as this will affect ease of insertion for new plywood.
3. Assuming you have already removed interior subfloor, it's time to insert new 3/4" tongue & groove plywood...I used tongue & groove. If you ripped a piece lengthwise, about 12" wide, and faced the tongue to the interior of the home it will be easier than trying to insert a full sheet of the plywood underneath the sill. I used full sheets and it was a tough job. With the tongue facing inward to home, you will eliminate the need for blocking. You also have to tear out less interior flooring to get started (you won't have to walk on joist edges).
4. Determine how to raise the wall in order to slip the plywood underneath the sill. I used a temporary horizontal 2 x 4 screwed to wall studs on outside of mobile home (spanning 8'), yet underneath the metal siding that was opened up. I used scab blocks wherever there were 1 x 4 wall studs.
5. Plywood on ground (outside) so floor jack won't sink into ground...use vertical 2 x 4 to mate underneath the horizontal 2 x 4 on wall...use jack to raise wall.
6. Insert manageable piece of tongue & groove plywood underneath sill (tongue to interior of home). Square this first piece good because it determines how rest of new tongue & groove flooring will mate up.
7. If inside finished walls are still in tact, you MUST fasten sill to new plywood floor from the outside of the mobile home. Nail gun or screws and impact driver work well for this.
8. Lower wall.
9. Repeat.
Two 14x66's