NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
22
H1
V
H
V
H
H1
Table F
H
+H1
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 + H1 = 40 feet (12.2 m) MaxH = 8 feet (2.438 meters) Max.H + H1 = 20 feet (6.096 meters) Max.Table GH + H1 Maximum V Minimumfeet (meter) feet (meter)3 (0.914) Elbow Only5 (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 + H1 = 40 feet (12.2 m) Max.H + H1 = 20 ft. (6.096 m) Max.
Wall Firestop/
Spacer (SV4.5HF)
Ceiling
Firestop / Spacer
(SV4.5VF)
Wall Firestop/
Spacer (SV4.5HF)
When using Secure Flex, use Firestop
/ Spacer SF4.5VF
When using Secure Flex, use Firestop
/ Spacer SF4.5HF
Note: See Table 11 as an aid in venting
component selection for a particular range
of exterior wall thicknesses.
Ceiling Firestop /
Spacer (SV4.5VF)
Wall Firestop/
Spacer (SV4.5HF)
Wall Firestop/
Spacer (SV4.5HF)
When using Secure Flex, use Firestop /
Spacer SF4.5VF
When using Secure Flex, use Firestop /
Spacer SF4.5HF
Note: See Table 11 as an aid in venting
component selection for a particular range
of exterior wall thicknesses.
Example: If 20 feet of (H + H1) 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+ H1) horizontal run, up to a maximum
horizontal run of 20 feet.
Example: If 20 feet of (H + H1) 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+ H1) 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 36.
Figure 37 - Side Vent, TWO 90 DEGREE ELBOWS
Figure 38 - Top Vent, TWO 90 DEGREE ELBOWS