Installation manual
www.fmiproducts.com
108918-01K10
VENTING INSTALLATION
Continued
14 
3
/
8
"
(36.5 cm)
30"
(76.2 cm)
1"
(2.5
cm)
1"
(2.5
cm)
Minimum Measurements
1"
(2.5 cm)
Opening "A"
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
4. Removeshingles aroundopeningmea-
sured.Cutoutthissection.
5. Add next sections of pipe until end
penetrates roof line. Check to see that
properclearancesaremaintained.Extend
chimneybyaddingsectionsofdoublewall
pipeuntilpipeisminimumof 30"above
highestpoint ofroof cutout.Termination
andchimneymustextendaminimumof
36"abovehighestpointwhereitpasses
throughroof.
Figure 14 - Roof Opening Measurements
FLASHING INSTALLATION (V6F-8DM 
OR V12F-8DM)
Determineashingtobeusedwithroofopen-
ingchart.Slideashingoverpipeuntilbaseis
atagainstroof.Replaceasmanyshinglesas
neededtocoverexposedareaandashing
base. Secure inpositionby nailing through
shingles(seeFigure15,page11).DONOT
NAILTHROUGHFLASHINGCONE.
Installing Flashing on a Metal Roof
When installing ashing on a metal roof, it
isrequiredthatputtytapebeusedbetween
ashingandroof.Flashingmustbesecured
toroofusing#8x3/4"screwsandthensealed
withroofcoatingtopreventleakagethrough
screwholes.Aroofcoatingmustalsobeap-
pliedaroundperimeterofashingtoprovide
aproperseal.
FIRESTOP SPACERS (3600FS-8DM-1)
Firestopspacersarerequiredateachpoint
where chimney penetrates a floor space.
Their purpose is to establish and maintain
required clearance between chimney and
combustible materials. When pipe passes
throughaframedopeningintoalivingspace
above,restop mustbe placedonto ceiling
frombelowasshowninFigure12.
Theyalsoprovidecompleteseparationfrom
oneoorspacetoanotheroratticspaceas
required by mostcodes.Whendouble wall
pipepasses througha framedopening into
anatticspace,restopmustbeplacedinto
anatticoorasshowninFigure13.
Figure 12 - Firestop Spacer with Living 
Space Above Ceiling
Figure 13 - Firestop Spacer with Attic 
Space Above Ceiling
PENETRATING ROOF
Tomaintaina2"clearancetopipeonaroofwith
apitch,arectangularopeningmustbecut.
1. Determine center point where pipe will
penetratetheroof.
2. Determinecenterpointoftheroof.Pitch
isthedistancetheroofdropsoveragiven
span,usually12".A6/12pitchmeansthat
theroof drops6" foreach 12"measure
horizontallydownfromroofrafters.
3. Use roof opening chart (Figure 14) to
determine correct opening length and
ashingrequired.
Ifareaaboveisalivingspace,install
restopbelowframedhole.
Ifareaaboveisanatticorinsulatedarea,
installrestopaboveframedhole.










