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125079-01F
15
VENTING INSTALLATION
Continued
Figure 17 - Offset with Wall Strap and 45°
Elbows
45° Elbow
Wall Strap
Roof Flashing
Ceiling Firestop
Flat Ceiling Installation
1. Cut a 11
1
/
2
" square hole in ceiling using locat
-
ing hole as a center point. Opening should be
framed to 11
1
/
2
" x 11
1
/
2
" inside dimensions, as
shown in Figure 10 on page 11 using framing
lumber the same size as ceiling joists. If area
above ceiling is an insulated ceiling or an attic,
nail firestop from top side. This prevents loose
insulation from falling into required clearance
space. If area above ceiling is a living space,
install firestop below framed hole. Firestop
should be installed with no less than three
nails per side (see Figure 17).
2. Assemble desired lengths of pipe and el
-
bows necessary to reach from fireplace flue
up through firestop. Be sure all pipe and
elbow connections are fully twist-locked
(see Figure 9, page 11).
3. Cut a hole in the roof using locating hole as
a center point. (Cover any exposed open
vent pipes before cutting hole in roof.) The
11
1
/
2
" x 11
1
/
2
" hole must be measured on
the horizontal; actual length may be larger
depending on pitch of roof. There must be
a 1" clearance from vent pipe to combus
-
tible materials. Frame opening as shown
in Figure 10, page 11.
4. Connect a section of pipe and extend up
through hole.
Note: If an offset is needed to avoid obstruc-
tions, you must support vent pipe every 3 feet.
Use wall straps for this purpose (see Figure
17). Whenever possible, use 45° elbows
instead of 90° elbows. The 45° elbow offers
less restriction to the flow of flue gases.
5. Place flashing over pipe section(s) extend
-
ing through roof. Secure base of flashing
to roof and framing with roofing nails. Be
sure roofing material overlaps top edge
of flashing as shown in Figure 17. There
must be a 1" clearance from vent pipe to
combustible materials.
Vent Termination Chart
Minimum Height
Roof Pitch
Feet Min.
Flat to 6/12
1
6/12 to 7/12
1.25
Over 7/12 to 8/12
1.5
Over 8/12 to 9/12
2
Over 9/12 to 10/12
2.5
Over 10/12 to 11/12
3.25
Over 11/12 to 12/12
4
Over 12/12 to 14/12
5
Over 14/12 to 16/12
6
Over 16/12 to 18/12
7
Over 18/12 to 20/12
7.5
Over 20/12 to 21/12
8.0
Vertical Termination Installation
Note:
Vertical restrictor
must be installed in
all vertical installations.
1. Determine route your vertical venting
will take. If ceiling joists, roof rafters or
other framing will obstruct venting system,
consider an offset (see Figure 17) to avoid
cutting load bearing members.
Note: Pay
special attention to these installation
instructions for required clearances (air
space) to combustibles when passing
through ceilings, walls, roofs, enclosures,
attic rafters, etc. Do not pack air spaces
with insulation. Also note maximum
vertical rise of venting system and any
maximum horizontal offset limitations.
2. Set fireplace in desired location. Drop a
plumb line down from ceiling to position
of fireplace exit flue. Mark center point
where vent will penetrate ceiling. Drill a
small locating hole at this point.
3. Drop a plumb line from inside of roof to
locating hole in ceiling. Mark center point
where vent will penetrate roof. Drill a small
locating hole at this point.
