Installation Guide
5
Table 1
DuraTech Cimney Components
12”, 18”, 24” & 36” SECTIONS  ROUND CEILING SUPPORT BOX 
FIRESTOP RADIATION SHIELD EXTENDED ROOF BRACKET
ELBOW ATTIC 
TRIM COLLARS FOR ROUND 
SUPPORT BOXES 
INSULATION SHIELD ADJUSTABLE ROOF FLASHING
TEE WITH TEE CAP  WALL THIMBLE 
ELBOW STRAP CHASE TOP FLASHING
TEE SUPPORT  FINISHING COLLAR 
BRACKET WALL STRAP FLAT ROOF FLASHING
CHIMNEY CAP  ROOF RADIATION SHIELDS 
ANCHOR PLATE STORM COLLAR
CHIMNEY DIAMETER
Follow the appliance manufacturer’s 
instructions to determine chimney diameter 
and clearances between combustible materials 
and your heating appliance. Never choose a 
chimney with an inside diameter smaller than 
your appliance’s outlet. If you are connecting 
to a masonry replace, refer to Table 4, for 
proper sizing. To calculate the chimney’s 
outside diameter, add 2 inches to the inside 
diameter. 
CHIMNEY HEIGHT 
The National Fire Protection Association 
Standard #211 states: “Chimneys shall 
extend at least three feet above the highest 
point where it passes through the roof of a 
building, and at least two feet higher than 
any portion of a building within ten feet.” (Fig 
1) 10”-16" diameter DuraTech Chimney may 
be installed up to 40 feet high when using a 
Support Box, and up to 30 feet high when 
using a Tee Support. DuraTech in 18”-24” 
diameters is intended to be mounted directly 
to an appliance or masonry replace, and is 
limited in height by the allowable weight of the 
supporting surface, up to a maximum of 60-ft. 
If the chimney extends more than 4 feet above 
the roof, an Extended Roof Bracket must be 
used. Due to the overlap of the joints, subtract 
3/4” from each Chimney Section’s height to 
calculate installed height.
CHIMNEY PLACEMENT
When deciding the location of your chimney, 
try to avoid modications to roof beams and 
other structural components of the building. 
CHIMNEY ENCLOSURE 
REQUIREMENTS 
Through Rooms:  Interior chimneys shall 
be enclosed where they extend through 
closets, storage areas, occupied spaces, or 
anyplace where the surface of the chimney 
could be contacted by persons or combustible 
materials. The space between the outer wall 
of the chimney and the enclosure shall be at 
Figure 1
2 FT. MIN. ABOVE
HIGHEST POINT OF
ROOF WITHIN 10 FT.
3 FT. 
MIN. 
ABOVE
ROOF
10'










