I have an old house with a stone foundation and ~6x6 sill plate. The deck used to butt right up to the siding. I cut the deck away about 18" in order to get access to the area for some weatherization... removed some courses of clapboards, sheathing boards (T&G), and did some spray foaming. My question now is, should I take any measures to protect the foundation, sill, and siding from moisture - particularly snow that will fall from above and/or drift?
I was thinking several inches high metal flashing extending to an inch or two below the sill to a few inches above it. But then how would I attach the clapboards? Is there a better alternative? Or will I just have to live with replacing those clapboards sooner than the rest of them?
Here's a schematic (side view) to illustrate:
The vertical line represents proposed flashing.