I am planning on replacing my current wood retaining wall with a dry stack concrete block wall- the ones that can be purchased from HD/Lowes. I have a question regarding the foundation. Some of the information I have read indicates using crushed gravel as the foundation while other information I have read makes no reference to crushed gravel. Also in talking with some people at work, some have indicated using stone dust. My question is what should I use for the foundation: crushed gravel, stone dust or neither? This wall will be no higher than 2 ft, but I do want to have the proper foundation so this wall will last (it will be exposed to freezing temperatures). Any help is greatly appreciated.

 

Dig a shallow trench about 4 to 6 inches deep and a little wider than the block. Fill the trench with about 2 inches of crushed rock, then level and compact the rock to form a flat and solid base.