Raised Patio w/Concrete Slab

Discussion in 'Hardscaping' started by turfquip, Mar 24, 2007.

  1. turfquip

    turfquip LawnSite Senior Member
    Messages: 860

    A customer (good friend) has requested a raised patio constructed of SRW, then concrete poured within, flush to the top of the wall. The customer will handle the pour, I will be responsible for constructing the wall to contain it.

    At the furthest point, the wall (patio) will only be approximately 16" high. My idea is to add a pedestal style, continuous step along the wall's curvature at highest point.

    My immediate question is which wall system would you guys recommend for this application? Let me backup first and ask if this is even possible since the wall will need to act as a form for the pour?

    Where the wall is 16" high, I will be adding, leveling and compacting base material up until the final 4 inches remain, for the concrete.
  2. turfquip

    turfquip LawnSite Senior Member
    Messages: 860

    No responses yet, which suggests the question or the commentary surrounding it may have been confusing to the reader(s). I apologize for that!

    I used the term pedestal style, when in fact we are talking about only one step at the 16" point which means no pedestal stack up will be necessary. My bad.

    Back to specifics. A hollow core wall block wont finish out without a cap, with concrete poured to top of the cap. Question, will a glued cap resist the lateral forces of 4" of concrete? My guess is no, it wont but this is where my inexperience is glaringly obvious. Do caps from some systems pin on? This seemingly would resist the moment to push out.

    Please advise...
  3. McKeeLand

    McKeeLand LawnSite Senior Member
    Messages: 681

    In regards to you cap question, most srw systems use a cap that glues with masonry adhesive to the top of the block. even if it is a pin system it still can be glued down instead. as long as the glue is allowed to cure the specified amount of time on the tube it will be plenty strong to retain your concrete pour. you will of course need expansion along the perimeter between the cap and slab. i have not done a lot of this application, i usually talk the customer out of it and into a paver. you have to install the base anyway, so why not put down the pavers at that point. maybe so one on here with more experience with this can give you more specific advice on this. hope it helps.
  4. DVS Hardscaper

    DVS Hardscaper LawnSite Fanatic
    Messages: 6,623

    good too hear from ya mr x,

    a cured, glued cap will more than likely not resist.
  5. McKeeLand

    McKeeLand LawnSite Senior Member
    Messages: 681

    i don't see why it would not. i have seen it done. if he is concerned about to much of a load on it than break off the pour in to 2 or three depending on how large of a patio. i mean if a wall can withstand 24" of flow fill with noting more than gravity holding it up at that point why not 4" on the cap. i don't see how when we have to chisel the caps off with a hammer that they would fail.
  6. bigviclbi

    bigviclbi LawnSite Senior Member
    from nj
    Messages: 901

    Why not just form it so that you can glue the caps on after the pour?
  7. cgland

    cgland LawnSite Bronze Member
    Messages: 1,929

    As long as the expansion material is placed between the cap and the pour you should not have a problem. After all, 1" of that pour will be below the cap (if it's a 3" cap), so that should help. By the way, I think it's a stupid idea, but it should work.

  8. Lazer_Z

    Lazer_Z LawnSite Silver Member
    from NJ
    Messages: 2,578

    Come on Chris, tell us how you really feel lol.

  9. chris638

    chris638 LawnSite Member
    Messages: 149

    Depends on what type of wall system being used. Allan Block caps are notched at the front meaning that you don't even need to glue them on. By the time set the cap in place and pour concrete behind them, there is very little chance of moving them. Still a little confused by the step thing though.
  10. Dirty Water

    Dirty Water LawnSite Fanatic
    Messages: 6,794

    I would build the wall, and then form up a 4" form for the pad ontop of the wall (set it in one inch). Thin trex boards work well for this, use lots of stakes.

    Do the pour, and make sure you install a expansion joint, and then strip forms and glue the caps on.

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