Ned Harr wrote:
The thing I don't understand is why, in the rendering on the right, water can be simply diverted around the structure, but it can't be on the left--why wouldn't the left-side structure-builder use whatever those same means are to divert water? ...
Am I missing something?
I believe this has something do do with how the structure is placed on the lot.
The structure on the left has been place below grade causing the water to run onto the structure basically the roof.
The structure on the right was place higher on grade so that the water runs off before getting to the structure.
When ever we have built a structure we find the highest elevation to build the structure thus avoiding water running into the structure.