View Full Version : Retaining wall on slope.

Heller Landscaping
03-31-2003, 06:24 PM
I was asked to bid on a retaining wall that that runs on a slope along a drive way. It is about 26' long and starts out at one block and cap and ends with about three or four blocks and a cap. Please give any and all suggestions. Pics would really be helpful.
I was thinking of using something like Pisa or Keystone blocks.
Any and all replies thanks in advance. :)

Groundcover Solutions
03-31-2003, 07:39 PM
These are a few pics of a wall we did a few years back, it is not the same material but it is on a slope and this is how we worked it! Hope that it is of some help to you.

Wall (http://hlandscape.com/Retainingwall/portfolio1.htm)

Heller Landscaping
04-01-2003, 07:12 PM
Great looking job Hometown That really helped me out. Thanks.:)

Bergbigler Lawn Care
04-01-2003, 10:47 PM
Heller, I have installed walls that were about the same dimensions that you are talking about, and bigger. I like using the keystone wall system. It is very easy to install. I am getting the idea that you are not real familiar with installing these walls, or is there some other info. you are looking for. Are you looking for how to install or pricing the job.

04-02-2003, 07:28 AM
Are you dealing with a slope running from left to right as well as the slope you are to retain? Are you looking to make a wall with a level top?

If that is the case, a fast way to excavate is to dig a trench a foot deeper that the finish grade will be in front of the wall. That will give you enough depth fo adequate base material and a fully buried block where you will have to step up a course under ground (realize that one end of one block will need to be buried where this happens or the base material next to it will be above grade).

Start at the low end of the wall and set the top of your gravel base an inch or so below where the final finish grade will be. Continue with the gravel at that level untill you are deeper than the height of one course of the type of block that you are using (go an extra couple of feet). Do your compaction...set the base course untill the top of the course is below grade. Get the drain pipe in, backfill and infill (keystone) to stabilize the course. Then continue the gravel base at the top of that course and repeat as necessary.

I think that is what you were asking ... I don't know.

Heller Landscaping
04-02-2003, 08:29 AM
Bergbigler Yes I have done some small walls but everything was on the level. This wall is on a slope. I wish I had a digital cam I would post pics.:(

AGLA Thanks you really explained it well. I could almost visualize it as I read your post.

Any difference pricing a wall on a slope and do you need anything like a transit?

Btw what base do you guys put down?


Groundcover Solutions
04-02-2003, 12:59 PM
We do not charge any different for a slop because we incorporate the cost into every stone that we put in so the when you do a slope you use more materials therefore the cost goes up. also as to the base material we use what is called slag sand we dig about a 2-3 in trench and put slag down level it and then put the first level on and level that after that it is all smooth sailing. we just make the trench deeper until that level goes into the slope and we start the process over again! I hope that this makes sens! and thanks for the complement on our job!!!!

Bergbigler Lawn Care
04-02-2003, 10:32 PM
For the base we use 2A Limestone. We use 2B Limestone for backfilling. As for charging more just because it is on a slope, well I have charged more on some because of the slope and have not on others that were on a slope. It really depends on how you charge for the job and if the work is more involved that it is necessary to charge more. AGLA really did a well job at walking through the process, I could not have explained it that well myself. Good luck with the job!

04-03-2003, 06:47 AM
You should use a transit, or actually a dumpy level (transit turns horizontal and vertical angles, dumpy level justs sites at level).

Whether or not you are using a dumpy level, you will speed things up by puting a stakes at both ends of where your gravel base is going and running a tight masons line from one to the other. This will establish a flat plane for you to fill your base to. As long as you are just a hair below that string, it will continue to vibrate when you pluck it like a guitar. If it does not, then the gravel is too high somewhere. You must rake it down untill the string vibrates. Although it looks level or close enough, it won't be if it does not vibrate.

When the first base course is set, set another stake at the end of the next section of gravel base. Now attach the masons line to the very first stake - this time at the top of the base course block. Run it all the way to the far end of the next level of base gravel. Lower the string untill it is just a hair above the existing base course of blocks and tie it to the stake. This will project the same plane as the top of the block for you to place your base gravel. That will keep the top of your wall flat all the way through your project.

Remember that the string has to vibrate or it will not work. Any little kink in the base course gets multiplied with each course you go up.

Good luck - a dumpy level kit usually runs about $300 for tripod, rod, and level head. I like the Berger over the David White - these seem to be the most widely available ones in this price.

Heller Landscaping
04-03-2003, 08:52 AM
Thanks Guys for all the help. I hope I get the job.:) You guys really helped me out and I appreciate it. I will let you know how it goes. Thanks.