2015 NECB Question, Intersecting Floor and Wall Area

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Good morning,

For you Canadians, I have a question about how to model the area where a
floor slab intersects the exterior wall.

Specifically, Section 3.1.1.7.8) of the 2015 NECB says that "wall
assemblies shall be considered to include all related structural framing
and perimeter areas of intersecting interior walls *but shall not include
the perimeter areas where floor or roof slabs interrupt the wall's
construction." *

There is a reference to Note A-3.1.1.7.(8) which provides an illustration
to depict the extent of the surface that is considered as a wall at the
intersection with a floor. In this note, it also says "This Code may have
different requirements for the perimeter area of floors."

Since I haven't seen any such requirements (how anyone else), I'm not sure
how to treat this area.

When I have a building in which the insulating layer in the exterior wall
assembly is intersected by the floor slab (thus breaking the insulation
plane), I typically model my Proposed building with a separate assembly for
the slab edge and assign a low R-value (reflective of a wall with no
insulation).

My question then is, in this case, what would people model for the
Reference model in terms of R-value at the slab edge (where the floor
intersects the wall)?

As mentioned, I have not seen anything in NECB that specifically deals with
the treatment of the slab edge (other than at grade level). Would the
Reference model carry the same R-value as the Proposed model?

Thank you in advance for your input and thoughts.

Chris

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