NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
20
H
1
V
H
Wall
Firestop/Spacer
(SV4.5HF)
Ceiling
Firestop/Spacer
(SV4.5VF)
Wh
en using
Secure Flex, use
Firestop/Spacer
SF4.5HF.
When using
Secure Flex, use
Firestop/Spac
er
SF4.5VF.
V
H
H
1
Wall Firestop/Spacer
(SV4.5HF)
Wall Firestop/Spacer
(SV4.5HF)
When
using
Secure Flex
,
us
e
Firestop/Spacer
SF4.5HF.
Ceiling
Firestop/Spacer
(SV4.5VF)
Note - When usin
g
Secure Fle
x, us
e
Firesto
p
/Spacer SF4.5VF.
Table J
H + H
1
Maximum
V Minimum
feet (meter) feet (meter)
3 (0.914) Elbow Only
5 (1.524) 1 (0.305)
10 (3.048) 2 (0.610)
15 (4.572) 3 (0.914)
20 (6.096) 4 (1.219)
V + H + H
1
= 40 feet (12.2 m) Max.
H + H
1
= 20 ft. (6.096 m) Max.
Figure 39 - Rear Vent - TWO 90 DEGREE ELBOWS
Figure 40 - Top Vent - TWO 90 DEGREE ELBOWS
See Table 12 on Page 19 as an aid in venting component
selection for a particular range of exterior wall thick-
nesses.
Square termination (SV4.5HT-2) shown.
Square termination (SV4.5HT-2) shown.
See Table 12 on Page 19 as an aid in venting
component selection for a particular range of
exterior wall thicknesses.
HORIZONTAL VENT FIGURES / TABLES (CONTINUED)
Table H
H
+H
1
Maximum H
Maximum
V Minimum
feet (meter) feet (meter) feet (meter)
5 (1.524) 2 (0.610) 1 (0.305)
10 (3.048) 4 (1.219) 2 (0.610)
15 (4.572) 6 (1.829) 3 (0.914)
20 (6.096) 8 (2.438) 4 (1.219)
V + H + H
1
= 40 feet (12.2 m) Max
H = 8 feet (2.438 meters) Max.
H + H
1
= 20 feet (6.096 meters) Max.
Example: If 20 feet of (H + H
1
) horizontal vent run is needed,
then 4 feet minimum of (V) vertical vent will be required.
This table shows a 1(V) to 5(H) ratio. For every 1 foot of (V)
vertical, you are allowed 5 feet of (H+ H
1
) horizontal run, up
to a maximum horizontal run of 20 feet.
Example: If 20 feet of (H + H
1
) horizontal vent run is needed,
then 4 feet minimum of (V) vertical vent will be required.
This table shows a 1(V) to 5(H) ratio. For every 1 foot of (V)
vertical, you are allowed 5 feet of (H+ H
1
) horizontal run, up
to a maximum horizontal run of 20 feet.
An elbow is acceptable as 1 foot of vertical rise except where
an elbow is the only vertical component in the system. See
Figure 37.