21
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 11-inch X 11-inch (280mm X 280mm) hole through
the ceiling, using the centerpoint previously marked.
Frame the hole with framing lumber the same size as the
ceiling joists.
Figure 18. Ceiling Firestop (Ceiling Side)
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.
Figure 17. 11" x 11" Hole & New Framing Members
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).
Figure 19. Attic Firestop
JOIST
CEILING FIRESTOP
CEILING
NAILS (4 REQUIRED)
CEILING
CEILING FIRESTOP
RAFTER
NAILS (4 REQUIRED)
CEILING
NEW
FRAMING
MEMBERS
EXISTING CEILING
JOISTS
CHIMNEY
HOLE
11" (280 mm)
11" (280mm)