24
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 10-inch x 10-inch (254mm x 254mm) hole through
the ceiling, using the centerpoint previously marked.
Frame the hole with framing lumber the same size as the
ceiling joists.
Figure 22. 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 21. 10" x 10" 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.
Figure 23 shows an attic installation. Keep insulation away
from the vent pipe at least 1 inch (25mm).
While it is not mandatory, it is strongly recommended that
an attic insulation shield be used whenever insulation can
come in contact with the vent pipe. Follow your local building
codes.
Figure 23. 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
10" (254mm)
10"
(254mm)
NOTE: There must be NO INSULATION or other
combustibles inside the framed firestop opening.