Header in a fire rated assembly

The north wall has to be fire rated. Here in Toronto, the requirement for header in a fire rated assembly can be satisfied by having 5/8″ Type-X drywall installed next to the rim board. The 5/8″ Type-X drywall provides 40 minutes of fire-resistance ratings. Add the rim board and the plywood and we will get the required 45 minutes fire-resistance rating that’s required.