Installation Guide
15
ceiling and roof exists, as shown in Figure 
18 (Low Attic), rst cut and frame a ceiling 
opening as described in Ceiling-Supported 
Installations (Step 2). Refer to Table 2 for 
clearance and framing specications. If it is 
desired to install through a cathedral ceiling 
(Fig 19), then the hole is cut in the roof.
3. Install Support Box: Slip the Square 
Support Box, Reduced Clearance Support 
Box, or the CAS Ceiling Support into the 
framed opening so the square portion projects 
at least 2 inches below the nished ceiling and 
rafters (bottom of round portion is 5” below), 
and extends above the ceiling to framing or 
decking materials to which it can be nailed. 
Level the Support Box, and slit the corners 
to the rooine where they extend beyond it. 
Bend the aps (created by the slitting) ush 
with the roof, and nail the Support Box to the 
roof or framing with at least three (3) 8-penny 
nails, or (3) 1-1/2”, #8 screws, per side (Fig 
20). Be sure to keep the Support Box level. 
Screw the trim sections into the ceiling (Fig 6).
4. Complete Installation: Refer to Steps 7, 
9 & 10 in the Ceiling Supported Installation 
section to complete the Roof Supported 
installation.
Figure 20
Figure 21
(2) A Roof Support is also used in installations 
where there is a cathedral ceiling, and a 
Square Ceiling Support is not desired. The 
Roof Support allows the DuraTech chimney 
to come down into the room below the level 
of the ceiling (Fig 21). The Roof Support can 
support a maximum of 45 feet of DuraTech 
Chimney total, and maximum of 20 feet below 
the support. If a taller stack of DuraTech 
Chimney is required, you must use a Square 
Ceiling Support Box instead.
1.  Cut and frame opening to provide a 
minimum 2” clearance on all sides of the 
chimney pipe. Note: Opening in nished 
ceiling should be circular/oval in order for it to 
be covered by Trim Collar.
2.  Bolt on the Roof Support Brackets to 
the Roof Support Band using the supplied 
ROOF SUPPORT 
TRIM COLLAR
FINISHING COLLAR
DURABLACK
SLIP CONNECTOR
USE 4 NAILS (OR 
SCREWS) ON 
EACH SIDE OF 
SUPPORT
ROOF SUPPORT 
(SUPPORT 
BRACKETS AND 
BAND)
SECURE ROOF 
SUPPORT BAND TO 
CHIMNEY USING 
4 SHEET METAL 
SCREWS
TIGHTEN BOLT 
ON ROOF 
SUPPORT BAND.










