Empire Comfort Systems DVCT40CSP95N-1 Installation Instructions Manual page 21

Vertical Firestops
Vertical runs which pass through ceilings require 1 ceiling firestop
at the hole in each ceiling through which the vent passes.
Position a plumb bob directly over the center of the vertical vent
component and mark the ceiling to establish the center point of the
vent. Drill a hole through this center point and check the floor above
for any obstructions such as wiring or plumbing runs. Reposition the
appliance and vent system, if necessary, to accommodate ceiling
joists and/or obstructions.
Cut a 10-5/8 inch x 10-5/8 inch hole through the ceiling using the
center point previously marked. Frame the hole with framing lumber
the same size as the ceiling joists. See Figure 29. 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.
See Figure 30. If the area above the ceiling is an attic, position and
secure the firestop on top of the previously framed hole.
See Figure 31.
NOTICE: Remove insulation from the framed area in the attic before
installing the firestop and vent pipes.
40651-2-0320
VENT FRAMING (CONT'D)
Figure 29
Figure 30
Finishing
Finish the walls with the material of your choice. Figures 2 and 4 on
page 10 shows the minimum vertical and corresponding maximum
horizontal dimensions of mantels or other combustible projections
above the top front edge of the fireplace.
Only non-combustible materials may be used to cover the black
fireplace front.
Figure 31
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