DIY retaining wall using treated lumber

[Kirk R.]

my old wood retraining wall is rotted out. 

Lowes has on sale for $2.50.

Severe Weather (Actual: 3-in x 4-in x 8-ft) Pressure Treated Landscape Timber

How would you attach these? nails? spikes? 

would the 3 inch or 4 inch of the new wood go against the old ties? 

How to meet match up the corners? 

I've got the space to justI'm planning leave the rotting ties & build around. 

Any hints or tips for success or how to do on the cheap? 

Also best way to cut tge lumber.  i have a saws all.  but it doesn't cut that straight (could be operator error! :)) 

thanks

[JD Martin]

Don't burn it. You don't want to turn the toxic preserves into vapors.

Those landscape timbers will last close to 30 years. I have a wall that I built from them 26 years ago that is not rotted out yet but is starting to look its age. 

You can use long landscape spikes or rebar. I used spikes on my wall 26 years ago and it held together perfectly. On the bottom you can either spike it into the ground (if you have heavy clay or want to drive rebar very deep) or you can cut dead men and use them to anchor the wall into the soil behind it. Deadmen will hold the wall straighter over time but that "hill" you have is so slight anything is going to work there.

Can you build in front of it? Of course. If it were me, for looks, I would tear out the wood and continue with the paver wall next to it. But if you don't want to do that, build a wall in front of everything and bury it. Nothing is going to happen. That wall looks like it's not bigger than 2 feet in height. 

Cutting this lumber: use a circular saw. Buy a cheap Skil one if you don't want to spend the money, it will run you maybe 50 bucks. Wear a facemask if you can find one. Build the new wall about 6 inches in front of the old and backfill with gravel up to about 6 inches from the top. Wrap the gravel in fabric cloth if you want something that will last 30 years. If not, just fill it with gravel and add some topsoil on the top (or mulch, if you are doing what's in the bed there).