Need Direction on Hardscape Questions

I am new to the site, and have several questions about building a retaining wall. The first question is, which forum(s) do I need to post to?

Thank you for your help!

cdun2

I did a DG search and couldn't find any directions on building retaining walls. I did do a google search: "How to build a retaining wall." Lots of information/instructions came up.

I built a short wall last year out of the larger 4x6" landscape timbers , and am having a much larger project done this year (hired out).

Your wall would be built differently if it is a low wall (mostly aesthetic), or one that really needs to support the weight of a lot of soil. I think over 3' there are code issues, inspections required, etc.

What material were you thinking of using? How tall does the wall need to be?

It will be about 3ft tall and 120 feet long. Something along the lines of Jumbo Nursery Block is what I am thinking about using. Some sort of interlocking stone that would do well for a DIY project. This wall will replace one that was build with railroad ties (they are rotting). The wall will not have to hold back a lot of weight, but I will need a good drainage system.

A 3' wall does hold a considerable weight.

I bought a dorky book from home depot called "Patios and Landscape Construction 1-2-3". It was helpful since I had no idea what I was doing, but any brand of landscape blocks you buy will probably have the documentation about installation online.

The hard part of the wall I built was the excavation. You'll need to dig a trench wider than the blocks and about 6" deeper than the bottom row will be. With a 3' x 120' wall, that is going to be a HUGE project. I did my 40' one by hand with a shovel and pick axe, and probably won't ever do that again. We have hard clay here. If it was softer soil it would have been ok. Hopefully you have access to some equipment. The wall requires a 4-6" base of gravel, and then you'll need a french drain behind it too, so you'll need enough gravel that you'll want to have a truckload delivered. I didn't go quite wide or deep enough at my first attempt and regretted it. The more DIY variety landscape blocks have a ledge at the back that hooks over the previous row. The more heavy duty ones go together with pins. With 3' I'd lean towards the pinned ones if they aren't out of the budget.

Thanks for the detail, this is very helpful. I'm going into this with the thought that it will take me a better part of the summer to do it. I've spent Summers doing farm work, and have done some large landscaping projects, so I'm not to worried about the back work involved. What's more scarry are the quotes I'm getting from contractors to do this work. I got one last week where the guy wanted 3K just to remove the old wall!

I know! Our quotes have been outrageous and all over the place. I was floored.

Roger from Ask This Old House program built a retaining wall recently. Maybe there's a video on their website.

If you can rent some equipment to help with the excavation, I'd really advise it. It would be nothing near the cost of hiring someone for the job, but you can save yourself the stress on your body and do something more fun/ productive with your summer.

What kind of equipment am I going to need to rent?

cdun2 - I'm from Franklin (Hi) and my son and I built a small retaining wall that has held up pretty well. We've been using landscapers and contractors a lot since in this economy they've worked for half price. They evaluated a wall and the cost was enormous due to the "below ground" work and materials needed. Drainage was the biggest issue. I finally built a huge berm that curved around the yard, directed water flow and acted as a natural retaining wall. Lots cheaper and great place to plant.