Astria.us.com
127051-01_E
10
VENTING INSTALLATION
Continued
Pitch
Slope Opening "A"
Max.
Used Flashing
Model No.
Flat
0°
15"
V6F-8DM
0-6/12
26.6°
16
1
/
8
"
V6F-8DM
6/12- 12/12
45.0°
20
3
/
8
"
V12F-8DM
Figure 12 - Roof Opening Measurements
FLASHING INSTALLATION (V6F-8DM OR V12F-8DM)
Determine flashing to be used with roof opening chart. Slide flashing
over pipe until base is flat against roof. Replace as many shingles as
needed to cover exposed area and flashing base. Secure in position
by nailing through shingles (see Figure 13). DO NOT NAIL THROUGH
FLASHING CONE.
Installing Flashing on a Metal Roof
When installing flashing on a metal roof, it is required that putty tape
be used between flashing and roof. Flashing must be secured to roof
using #8 x 3/4" screws and then sealed with roof coating to prevent
leakage through screw holes. A roof coating must also be applied
around perimeter of flashing to provide a proper seal.
Figure 13 - Flashing Installation
Nail Only Outer
Perimeter of
Flashing
Storm Collar
Underlap Shingles at
Bottom
Flashing Cone
Overlap
Shingles Top
and Sides Only
FIRESTOP SPACERS (3600FS-8DM-1)
Firestop spacers are required at each point where chimney penetrates
a floor space. Their purpose is to establish and maintain required
clearance between chimney and combustible materials. When pipe
passes through a framed opening into a living space above, firestop
must be placed onto ceiling from below as shown in Figure 10.
They also provide complete separation from one floor space to an-
other or attic space as required by most codes. When double wall
pipe passes through a framed opening into an attic space, firestop
must be placed into an attic floor as shown in Figure 11.
Figure 10 - Firestop Spacer with Living Space Above Ceiling
Figure 11 - Firestop Spacer with Attic Space Above Ceiling
IMPORTANT NOTICE
When penetrating a ceiling into an attic, a firestop thimble
(38FST or FST30) is required to avoid intrusion by insulation
and recommended to negotiate a joist (see Figure 11a).
30"
(76.2 cm)
Minimum Measurements
Opening "A"
14
3
/
8
"
(48.3 cm)
1"
(2.54
cm)
1"
(2.54
cm)
1"
(2.54 cm)
Existing
Ceiling Frame
Firestop
Spacer
Screws or Staples
(Min. of 8)
Firestop Spacer
Screws or Staples
(Min. of 8)
Existing
Ceiling
Frame
Figure 11a - Firestop Thimble
Thimble 38FST
or FST30
Firestop
PENETRATING ROOF
To maintain a 1" clearance to pipe on a roof with a pitch, a rectangular
opening must be cut.
1. Determine center point where pipe will penetrate the roof.
2. Determine center point of the roof. Pitch is the distance the roof drops
over a given span, usually 12". A 6/12 pitch means that the roof drops
6" for each 12" measure horizontally down from roof rafters.
3. Use roof opening chart (Figure 12) to determine correct opening
length and flashing required.
4. Remove shingles around opening measured. Cut out this section.
5. Add next sections of pipe until end penetrates roof line. Check to
see that proper clearances are maintained. Extend chimney by add-
ing sections of double wall pipe until pipe is minimum of 30" above
highest point of roof cutout. Termination and chimney must extend
a minimum of 36" above highest point where it passes through roof.
