help on 3' egress window retaining wall

Discussion in 'Hardscaping' started by ibanez16, May 31, 2008.

  1. ibanez16

    ibanez16 LawnSite Member
    Posts: 2

    Hello,

    I am building an egress window well for my basement with a retaining wall that will be 3' high from base of first block (partialy burried) to top of the cap. I am using keystone compact blocks with pin system for this.

    My question is that my local dealer told me to use 1" washed stone - rough edged (not crushed) for the 12" backfill and keystone block core filler. This does not seem right. They also delivered what looks like a pea gravel, rough edge type about 1/4" in size vs what i actually ordered (1" washed stone). Would it be possible to use this as backfill? Is this a good idea?
    It looks like keystone may want 3/4" crushed stone as backfill and core filler, however I am not certain.
    The dealer I bought from from is very large and used by most contractors in the area with 30+ in the business. Yet I am still concerned about this.
    I currently have a firm base of crushed stone aprox 22" deep, with 3/4" washed stone in the middle (not crushed for central drainage (this is about 2' deeper then rest of hole).
    This hole is on a high grade and gets very little water, however its still quite possible during larger storms I could get a decent amount.
    I have no drainage system in place for this as well.
    I am not using a geogrid system for this particular wall.

    Any suggestions?

    Thanks,
    Jon
     
  2. PSUturf

    PSUturf LawnSite Senior Member
    Posts: 663

    "The drainage soil shall be a free draining angular granular material of a uniform particle size smaller than 1" separated from the retained soil by a geotextile filter." This is from Unilock's specs for constructing a gravity retaining wall. Washed stone and pea gravel refer to stone that is rounded water movement, found in river beds. What you need is crushed limestone of a uniform size without fine particles. If your stone looks like the attached picture than it is ok.

    If it were my house I would install a drain pipe, if possible, to remove water from the well..

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  3. ibanez16

    ibanez16 LawnSite Member
    Posts: 2

    Thanks for the info. The "pea gravel" looks just like the picture except 1/4" in size and very uniform in size no larger/smaller particles so should be no problem.

    As far as drainage goes, does anyone know of a good way to run drainage for an egress window?
    I was thinking it would not be a huge undertaking if i could put a drain higher in the hole, aprox 24" deep and run that back in my yard about 30' or so. Any suggestions on this? Does a drain have to be at the bottom of the wall? It seems many contractors tap into the basement, I didn't want to do this unless 100% necessary as I don't have my sump pump in the hole, my basement is that dry. Although I know its dry now, who knows some new construction could send the water flowing my way.

    There seems to be very little info specific to egress windows. All the contractors I consulted before in my area don't even use any type of backfill for a retaining wall this size, they literally put the bricks right up to the clay! Not to mention some used those castle wall style walls from home depot/Lowe's up about to 4' which seems like a disaster waiting to happen. Egress windows in existing residential is fairly new for my area due to new basement codes so I don't think there's many companies that have gotten into it yet. This is why I got into this project myself
     
  4. BrIONwoshMunky

    BrIONwoshMunky LawnSite Member
    Posts: 31

    The footer around the basement of your house should have a drain all the way around it. To find it, you should be able to dig a hole immediately against the outside wall. Around here the standard is a 4" corrugated ventilated pipe. A not-so-standard is what is called a 'form drain' which is shaped like a 2x4 and is actually a drainpipe and footer form all in one.

    Personally, I'd go down before I went out, but I'm not the one digging the hole either!

    If you are the original owner of the home, you probably have a pretty good idea if the footer drains exists, and if you don't know, the builder could probably tell you.
     

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