Vertical firestop

[Marc M]

Anyone know when vertical fire stop is necessary or under what conditions?

[Jerry Peck]

In a residential building fireblocking (versus firestopping) is required, in concealed spaces (which includes stud cavities in walls) vertically at floors and ceilings, and very 10 feet horizontally in vertical walls.

Draftstopping is required horizontally, in concealed spaces (such as floor/ceiling assemblies) every so many hundred square feet (I am drawing a blank on the number).

I suspect that you are referring to enclosing that chimney in a vertical chase, but it should be fireblocked at the ceiling level to the attic, so no chase would be required.

Presuming that local code or CA codes don't have specific requirements for that.

[Marc M]

Thank you sir..