I would like to build a raised landscape garden with 6×6 timbers alongside one of the exterior foundation walls to our home, and am thinking to just make it 3-sided (i.e., the foundation wall would serve as the back “side” and the timbers completing the box). It would be approximately 2-3′ deep.
My question is, is there any reason I should NOT do this for reasons of water infiltration into the foundation wall? It is a poured concrete wall and I know they put tar or other waterproofing on the surface below ground for a reason, so if I “raise” the ground against the wall without continuing any such waterproofing, am I asking for trouble?
Any advice/guidance appreciated. Thanks!