Installation Guide

PG 7
3. Flat Ceiling Support Box Installation: For a flat ceiling installation use the
Square Ceiling Support Box and Trim. The bottom of the Square Ceiling Support
Box must extend at least 2 inches below the finished ceiling (measured to the
bottom of the box not including the round adapter section) (Fig 5).
Level the Support Box and secure it to the framing using at least three 8-penny
nails per side (min. of 12 total). Alternatively, you may use 1-½” #8 wood screws
(min. of 12 total), instead of nails. Next, secure the Trim Collar to the framing
members using the provided hardware.
Vaulted Ceiling Support Box Installation: For a vaulted ceiling installation use
the 24” or 36” Square Ceiling Support Box and Trim. The bottom of the Support
Box must be a minimum of 2 inches below the finished ceiling at the lowest side
of the penetration (measured to the bottom of the box not including the round
adapter section) (Fig 5).
Level the Support Box and secure it to the framing using at least three 8-penny
nails per side (min. of 12 total). Alternatively, you may use 1-½” #8 wood screws
(min. of 12 total), instead of nails. Next, secure the Trim Collar to the framing
members using the provided hardware. Note: You will need to construct a
separate frame for the Attic Insulation Shield if the chimney is not fully enclosed
in a chase.
Cathedral Ceiling Support Box
Installation: For a cathedral ceiling
installation use the 24” or 36” Square Ceiling
Support Box and Trim. The bottom of the
Support Box must be a minimum of 2 inches
below the finished ceiling at the lowest side
of the penetration (measured to the bottom
of the box not including the round adapter
section) (Fig 5).
Level the Support Box and secure it to the
framing using at least three 8-penny nails
per side (min. of 12 total). Alternatively, you
may use 1-½” #8 wood screws (min. of 12
total), instead of nails. Next, secure the Trim
Collar to the framing members using the
provided hardware.
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