Sloped perimeter insulation for drainage plane at bottom plate/wall intersection in persist wall
I am in the process of designing a wall with thick exterior rigid insulation with “innie” windows and the drainage plane at the sheathing behind the foam.
The one area that I am concerned about is the spot where the bottom plate/wall sheathing meet the concrete/foundation insulation. Most articles I have found call for Z flashing from the WRB/Sheathing to down the outside of the foundation perimeter insulation. The problem I see with this is that the foundation foam is often described as being cut flush to the top of the concrete, which effectively means that the assembly will not have a sloped drainage plane that drains water away from the wall sheathing/plate. I see the bottom plate as a vulnerable area for water to sit. Ideally I would have the foundation insulation cut short of the concrete, but I will not have that option as I plan to use a EPS raft slab product where the foam is also the concrete form.
I always see it mentioned in water management techniques to add a sloped sill (often in the form of a clapboard) as a way to drain away any water that gets behind windows. Would it be a necessary or possible to do the same here in this case?
I have been trying to think of a strategy to do so, but see problems with the wall insulation creating an area of compression on the foundation insulation. In my case, I plan on having 8 inches of rigid foam, which is a long distance to create a drainage plane. I suppose I could always install the wall rigid insulation 1/2 an inch higher (with shims), which would give space to install metal flashing that is sloped, but that also creates a long area around the house that is no longer insulated.
I have attached an image that shows the area I am concerned with
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