Photo Source: Summerhill

9.36.2.10. (8) The joints between the foundation wall and the sill plate, between the sill plate and rim joist, between the rim joist and the subfloor material, and between the subfloor material and the bottom plate of the wall above shall be constructed airtight by

a) sealing all joints and junctions between the structural components, or

b) covering structural components with an air barrier material and sealing it to adjacent air barrier material.