Basement Fireblocking within HVAC Soffit
I'm in the process of finishing my basement and I have a question about fireblocking. I need to build a soffit around the HVAC, plumbing and various other utilities that run through the center of the basement. Constructing the soffit is not an issue, but I am not sure how to fireblock or draftstop (I'm not sure if that's the right word) this soffit space.
The soffit is about 4'6" wide, 13" tall and runs nearly the length of the basement, except it is interuppted by the utility room.
On the left side of the utility room, the soffit runs up against the concete wall of the basement so I know that fireblocking must be installed belolw the intersection point of the stud wall there. The soffit on that side is about 18' long.
On the right side of the utility room, the soffit hangs in the middle of the space, only intersecting with the floor joists above on both sides of the soffit box. This side is about 22' long.
My problem is I don't see how to place a layer of sheetrock above the utilities- everything is attached to the floor joists above. If I need to install a draftstop every 8' or 10', how do you fit it around the utilities to effectively stop the fire? Also, do I need to close off the space between the joists, and if so, what is the best manner?
Sorry for the list of questions, but I don't want to miss anything here.
Thanks for whatever help is offered.