Installation Guide
20
Flashing.  Using a Chase Top Flashing allows 
for a lower prole for the chimney. The Chase 
Top Flashing has an opening that is 3” larger 
in diameter than the DuraTech Chimney. If the 
Chase Top Flashing can t over your chase 
enclosure as required (Fig 29) then install as 
directed, or trim as needed.  However, if the 
Chase Top Flashing is smaller than your chase 
enclosure, you will need to provide a galvanized 
sheet capable of covering your chase and 
overhanging the sides by 1/2 - 3/4 inch. Attach 
the Chase Top Flashing to the galvanized sheet 
using appropriate sheet metal screws and non-
hardening waterproof sealant. Use the Chase 
Top Flashing Spacers to allow the proper air-gap 
clearances on the galvanized sheet. The Chase 
Top Flashing Spacers are available to insure 
that the proper air-gap is maintained. Figure 29 
displays in some detail, how these air gaps are 
established using the Spacers and Chase Top 
Flashing.  Secure the Chase Top Flashing to the 
chase using a sufcient number of #8, 1-1/2” 
wood screws, being careful to insure the air 
Figure 28
Figure 29
ALLOW MIN OF 2 INCHES 
AIR SPACE ON ALL SIDES
2 INCHES MIN
2 INCHES MIN
ALLOW 1 INCH AIR 
GAP BETWEEN STORM 
COLLAR AND CHASE TOP 
FLASHING
1/2 INCH AIR SPACE 
ESTABLISHED BY 
SPACERS
6 INCH MIN CLEARANCE 
BETWEEN BOTTOM OF 
CAP AND CHASE TOP 
FLASHING
1/4 INCH 
AIR 
SPACE
CHIMNEY CAP
STORM COLLAR
CHASE TOP 
FLASHING
CHIMNEY 
SECTIONS
SPACER
1/2 INCH
FRAMED CHASE 
ENCLOSURE
1/4 INCH










