Hi all,

I have a small specific question concerning a new run of Romex cable that I'm planning. To feed circuits in a furnished room in the attic of a home, I'm planning
To use the chimney chase to get from the basement to the attic. This chase has no fire stops and is clear all the way up.

My question is: in the basement, the area between the brick chimney and the framed in portion (plaster/lath) has a fireproof board closing it off down at the unfinished basement ceiling, which I suppose is there to prevent a fire drafting upwards and quickly traversing the chimney chase. Should I leave this board alone and drill a separate set of access holes in the side of the chimney chase to get the Romex cables into the space? Or is there a different way? (There are three total NM 12/2 cables which will be making the trip.)

Thanks in advance.

While it appears to be convenient a chimney chase is not a safe route for wiring. Do not breach the fire stop in the basement, you'll compromise the safety of your home.

The wood frame chase around a brick chimney is used for fishing wires often. This void is not considered as a hazard to wiring. The seal around the brick at the bottom is a fire stop, drilling through this will require the application of intumescent fire caulk around the cable and restore the violation of fire stop..

If the chimney was steel triple wall, this type of duct has clearances of combustibles to keep away.

If there is any question, check with your local building official or fire marshall.