For Vertical Runs - One ceiling firestop is REQUIRED at the hole in each ceiling through which the vent passes.
To install firestops for vertical runs that pass through ceilings:
•Position a plumb bob directly over the center of the verti- cal vent component.
•Mark the ceiling to establish the centerpoint of the vent.
•Drill a hole or drive a nail through this centerpoint.
•Check the floor above for any obstructions, such as wir- ing or plumbing runs.
•Reposition the fireplace and vent system, if necessary, to accommodate the ceiling joists and/or obstructions.
•Cut an
•Frame the hole with framing lumber the same size as the ceiling joists.
If the area above the ceiling is NOT an attic, position and secure the ceiling firestop on the ceiling side of the previously cut and framed hole.
JOIST
CEILING
NAILS (4 REQUIRED)
CEILING FIRESTOP
Figure 28. Ceiling Firestop (Ceiling Side)
11" (280 mm) or 10" (254 mm)
NEW
FRAMING
MEMBERS
CEILING
11" (280mm) or 10" (254mm)
CHIMNEY
HOLE
EXISTING CEILING JOISTS
If the area above the ceiling IS an attic, position and secure the firestop on top of the previously framed hole.
NOTE: Keep insulation away from the vent pipe at least 1 inch (25mm).
NOTE: There must be NO INSULATION or other combus- tibles inside the framed firestop opening.
NAILS (4 REQUIRED)
Figure 27. Hole & New Framing Members
RAFTER
CEILING
CEILING FIRESTOP
Figure 29. Attic Firestop
28