I have a garage at a house I have recently moved into. Over the years the soil has built up against the walls resulting in damp soaking through the wall. I have dug it all out and created a trench around the edge down to the concrete slab. My question is, "Should I tank the outside walls to prevent the problem in the future?" I should add that I plan to line out the garage as well to use as a workshop for my hobbies.