Quote Originally Posted by TheGrey View Post
Thanks for the tips!

I think this will be one thing that I end up hiring out- our yard has a terrible slope that is getting more terrible as the years go by. I can do some gruntwork, but this may be beyond my abilities.

Home Depot beat Santa Fe Sand & Gravel for block? That's amazing!
I'll second calling 811. It's free to you, and while they aren't perfect (not even close) they'll give you a good idea...

When you say your yard has a terrible slope, how steep of an angle are you talking about?
How tall of a wall do you need?
How long of a wall do you need?

These will help determine if your wall is really a DIY project or not. Depending on the details, you might have to add geogrid fabric in between layers of block to provide a tieback support.

This is what my backyard looked like when we first bought the place, and we ended up with almost 5' of wall in the far corner of the picture. (I need to get a picture of the yard now...)

How it started by ARNEWB, on Flickr

As for timber vs block, I would strongly suggest block. As Mtneer said, getting good enough treated lumber to survive long term anymore is nearly impossible. Pressure treating of wood has been wussified, as with most things anymore, compared to the past. If you can get actual creosote soaked railroad ties, maybe. But even those are hard to get your hands on now.

And yeah, Husky is 100% right: Plan the project out, and stage your materials with thought and care. It makes a huge difference in the labor required for a project like this. I had the advantage of owning a bobcat, which helped dramatically in moving the 18,000lbs of concrete blocks that I put in the back yard.

If you're buying in bulk, HD can put some pretty good pricing together. It's worth shopping all possible sources, even if you have a contractor do the work, so that you know what the blocks will cost and what the labor is costing you. The contractor might be able to get better pricing, but doing your own research helps.