30
ROOM ABOVE (non-insulated ceiling)
ATTIC ABOVE (insulated ceiling)
B
A
Ceilng firestop from
bottom
Ceiling firestop from
top
Note:
Use same dimensional lumber for framing
ceiling firestop and joists.
Figure 8.5 Installing the Ceiling Firestop
• Install a ceiling fi restop whenever chimney penetrates
ceiling/fl oor.
• Mark and cut an opening in ceiling as shown in
Figure 8.5.
• Frame the opening with the same size lumber used in
the ceiling joists.
• Nail the ceiling fi restop to the bottom of the ceiling joists
when there is a room above.
• Use an attic insulation shield if the ceiling is insulated.
The ceiling fi restop may then be attached above or below
the joists.
E. Install Ceiling FirestopsCAUTION! Risk of Fire! Ceiling fi restops must be used
whenever the chimney penetrates a ceiling/fl oor.
• Chase construction requires ceiling fi restops at each
fl oor or every 10 ft (3.05 m) of clear space.
• The ceiling fi restop slows spread of fi re and reduces cold
air infi ltration.
WARNING! Risk of Fire! DO NOT seal area between
fi restop opening and chimney pipe except where they
enter the attic or leave the warm air envelope of the
home (use 600° F sealant).
Heatilator • I100 • 35144 • Rev AA • 11/08
Catalog #
AB
in. mm in. mm
FS538 17 432 17 432
FS540 17 432 26 660