Need advice on half wall at top of stairs.

Discussion in 'The Garage' started by Ratski, Feb 5, 2013.

  1. Ratski

    Ratski Been here awhile

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    I'm building a half wall at the top of my second story stairs. I put up the first of two tonight and need some advice as to how to make them stronger. The end at the top of the stairs wobbles back and forth with little effort. How do I make this better? :ear

    Some pics to see what I'm working with...

    [​IMG]

    [​IMG]
    #1
  2. toothy

    toothy Grin

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    Can you cut some of the green color wallboard and run a sheet of 3/4 plywood up the stairwell face of the wall, bonding the lower wall with your pony wall?
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  3. Joetool

    Joetool Been here awhile

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    First, you need to double up the end 2x's and have them go down into the floor. Also, you can skin one side with 1/2 inch plywood an cut it into the full height wall some. Screww it every 6 inches and you wil create sort of a box beam. Also; stagger some 3.5 inch screws in the bottom plate.And, you need WAY more screws in your drywall; 6" on the edges and 12" in the field...
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  4. Flashmo

    Flashmo Whatever...

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    4x4 post or doubled 2x4 needs to go through the floor and tie into the framing below floor level using carriage bolts through a king stud made for the half wall instead of screws. Then sheet both sides of the half wall with luan to create a "web frame" before sheeting with the drywall.
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  5. advNZer?

    advNZer? Long timer

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    easiest way would prolly to have a post going to the roof.other ways could be a steel L bracket or two bolted/screwed to the floor(rebated in)
    Its not exactly a high traffic area behind it though,looks barely high enough to walk in there
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  6. muddywater

    muddywater Been here awhile

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    what he said with the steel bracket.
    needs to be heavy enough to not flex much and screwed to a floor joist, not just the subfloor.
    rebate=mortise ??....you can hide the bracket once flush under the floor covering. BTDT:deal
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  7. TheOtherBart

    TheOtherBart Long timer

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    This would work, although 3/4" would be way overkill for the purpose. The ply would essentially be in tension/compression as that wall got pushed on, so 1/4" would be plenty. In fact I'd bet that re-running your drywall so it was continuous over that joint would stiffen things up significantly.

    Depending on what's going to happen in that little space behind the half wall, you could add a little 6-12" L at the free end pointing away from the stairs.

    And hopefully you're screwing that bottom plate down, nails won't offer much resistance to pullout as that hall gets pushed in or out at the top.
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  8. Wkendwrench

    Wkendwrench Adventurer

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    In addition to above recommendations, if code will allow, consider making wall shorter by the width of the top step (12"?).
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  9. this is a RV

    this is a RV Been here awhile

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    Turn that wall into a bookcase or cabinet 12 or 20 inches deep.
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  10. r1200gs_chris

    r1200gs_chris Been here awhile

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    1st, skin the backside of the wall with plywood, 1/2" should do. Glue and screw (NO NAILS) the plywood to the studs. Go buy some construction adhesive. Don't be cheap with the screws, every 8-10 inches in each stud, run glue down all studs. 2nd, drill a few pilot holes and strew some 3"x1/2" lag bolts into the floor. The plywood will make the wall rigid, and the lag bolts will hold it to the floor. Most of the wiggle is coming from the fact that the nails are not keeping your joints tight. When you build the second wall fell free to put the construction adhesive between each joint for added strength.

    Good luck!
    #10
  11. GH41

    GH41 Been here awhile

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    I am betting this isn't a permitted job. The space behind the wall doesn't look like it could used for anything but storage. I would build the wall floor to ceiling. Any attempt to steady the wall with brackets to the floor is a waste of time. GH
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  12. Ratski

    Ratski Been here awhile

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    I like the plywood to tie it in to the lower wall. you guys are right, storage behind this wall, but there is gonna be a matching (but longer) wall on the other side of the stairs that will see a teenager boys traffic to his room and all of his friends, etc.. so any techniques will be applied to that side too. Keep the ideas coming.
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  13. toothy

    toothy Grin

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    Gluing it with construction adhesive is an excellent move, but skip the screws unless they are the GRK structural kind. Screws snap over time. Nails are the best bet in wood construction.
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  14. heirhead

    heirhead Been here awhile

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    Hello,

    Get rid of the drywall shims you put on the studs then cut the drywall down 2ft or so. Put up plywood, 1/2", or whatever thickness of drywall is to match. Adhesive is great, then screw the plywood to studs and screw both 2x4 plates off every 6 inches. Closer the better. You can put plywood, 48", to the top of plate and cut green drywall down to match but at least 1 ft. 2 ft is better. When you hang finish d/w, screw both plates all the way across and studs. Your kids couldn't tear this wall down if they tried. Also do not have the drywall joint and plywood joint be the same, stagger them by at least a ft. as to not have a d/w joint crack.
    USE GOOD SCREWS!!!
    Angle pieces on floor or from stud to plate not needed at all.
    Still worried, run some lags and big washers through both plates and the floor like R1200gs_chris said.
    Just looked close at your first pic. Where you ran d/w up on ceiling next to wall, that is called railroading or running same way as studs. Do NOT do this on wall. Run plywood and d/w horizontal. Also the piece that you ran up and down right next to the first stud, cut off at the height of wall and run d/w the whole length of the wall all the way to wall on left. What you have is called a cold joint and WILL crack out.Get a 12 ft piece of d/w, important to have the new wall, lower wall and side wall all one if possible.
    The big one will hit and this section of your house will still be together.
    What we said in Ca. when something is overbuilt!!
    Nomenclature is from SoCal.
    Retired from this kind of back breaking work,
    good luck,
    We don't need no stinking codes!!!!!!
    Heirhead
    Worlds worst mechanic
    Worlds worst sheet rocker
    #14
  15. r1200gs_chris

    r1200gs_chris Been here awhile

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    Well, we'll all given our 2 cents. Let's see what you came up with. Pics please.
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  16. jeiff

    jeiff Been here awhile

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    It would be interesting to see a graph that supports your opinion.
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  17. P B G

    P B G Long timer

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    Particularly since decks usually are screwed, as are balconies.
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  18. vivo

    vivo Adventurer

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    Sheath both sides in 1/2 cdx plywood, subfloor adhesive is good, 8 penny common nails 6" on center. If you run that plywood into the stairwell as suggested, 12" down is fine, you will have what you need. Cover in 1/2" Drywall.

    i am a carpenter

    Vivo
    #18
  19. slackmeyer

    slackmeyer Don't mean sheeit. .

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    Shear walls aren't. Engineers prefer nails for this application (plywood under shear) because nails have just enough give that the assembly functions all as one unit resisting the load. Screws have a much higher probability of snapping in series. Also, the failure mode of nails is much preferable; even when overloaded, the system holds up, rather than failing completely.

    Toothy's 100% right on this one, an engineer would call for nails here. Since I build a lot of shear walls, I'd probably use the nails I have for them: 2 1/4 x .148, a pretty thick 10d nail.

    Edit to add: If you're referring to the deck boards on a deck or patio, they usually are screwed. A lot of that is cosmetic (easier to get a screw set right with no marring around it), part of it is that the screws are less likely to pop up a bit above the deck board. Anyway, the structure of the deck is built with nails, metal hangers, and through bolts to hold the ledger to the building.
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  20. r1200gs_chris

    r1200gs_chris Been here awhile

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    I think you missed the "meat" of my post. I did not tell him to screw the studs together. I said use construction adhesive, then screw the plywood to the studs. The screws are just there to hold the plywood firm until the glue sets. Rocking that wall back and forth (teenagers) will cause the nails to come loose, guaranteed. The plywood and construction adhesive, plus lagging the wall into the floor joists will do their best to counteract all that teenage energy. I don't see where the shear force comes into play on a 4' tall wall, but I bet those screw will outlast that wall. The best thing to do is to run that plywood right down to the studs on the wall going up the stairs and glue and screw/nail/ them together, because the weak point is still going to be the nails used to hold the studs together and that wall will rock loose with enough force if not tied into the wall below it.

    Isn't this a sight about motorcycles? This is turning into an oil thread. I'd be more concerned about what type of paint you are going to use on those walls! :rofl

    Good luck!
    #20