I want to extend an existing wood retaining wall about 8 feet. Design is pretty straightforward. I plan on placing 4x6" vertical timbers on each end, with one in the middle at the 4' mark. Will use three 12" planks for the wall (one buried, two above ground), which is the same as the existing wall.
One question I have is how to join the new part of the wall with the old part. Should I place a new vertical post up against the old post? Or should I try to have the new wall sections attach to the existing post? The existing wall planks are flush with the outermost vertical post, so I'm not sure how I could attach the new wall planks to the old post. If I bury a new post up against the existing post, won't the concrete from the existing post get in the way?
Photos below are of existing wall and the area where the new wall will begin.
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One question I have is how to join the new part of the wall with the old part. Should I place a new vertical post up against the old post? Or should I try to have the new wall sections attach to the existing post? The existing wall planks are flush with the outermost vertical post, so I'm not sure how I could attach the new wall planks to the old post. If I bury a new post up against the existing post, won't the concrete from the existing post get in the way?
Photos below are of existing wall and the area where the new wall will begin.
