Property boundaries are not barriers to fire spread.
Existing parcel-centric codes offer limited or no protection to the neighboring parcel.
Shed is located far away from the house on Lot 1 but is too close to the neighboring house across the property boundary on Lot 2. Limiting code application within property lines leaves the hazard imposed from the shed to the neighboring house unmitigated.
When the property boundary is ignored and the potential exposure is considered, the shed is located far away from both residences.