25
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
HORIZONTAL VENT FIGURES/TABLES (continued)
V
H2
H1
H
Table J
H + H1 + H2 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 + H2 = 40 feet (12.2 m) Max
H = 8 feet (2.438 meters) Max.
H + H1+ H2 = 20 feet (6.096 meters) Max.
Example: If 20 feet total (H+H1+H2)
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 horizontal run
up to a maximum total (H+H1+H2)
horizontal run of 20 feet.
Table K
H + H1 Maximum V Minimum
feet (meter) feet (meter)
5(1.524)
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)
H + H1 = 20 feet (6.096 m) Max.
V + V1+ H + H1 = 40 ft. (12.192 m) Max.
V
H
H1
V1
v Wall Firestop / Spacer
(SV4.5HF)
uCeiling Firestop /
Spacer (SV4.5VF)
uCeiling Firestop /
Spacer (SV4.5VF)
v Wall Firestop
/ Spacer (SV4.5HF)
vWall Firestop / Spacer
(SV4.5HF)
Figure 47 - Side Vent, THREE 90 DEGREE ELBOWS
Square termination (SV4.5HT-2) shown
Square termination
(SV4.5HT-2) shown.
Figure 48 - Top Vent, THREE 90 DEGREE ELBOWS
u When using Secure Flex, use
Firestop / Spacer SF4.5VF
v When using Secure Flex, use
Firestop / Spacer SF4.5HF
Note: See Table 8 as an aid in
venting component selection for
a particular range of exterior wall
thicknesses.
u When using Secure Flex,
use Firestop / Spacer
SF4.5VF
v When using Secure Flex,
use Firestop / Spacer
SF4.5HF
Note: See Table 8 as an aid
in venting component selec-
tion for a particular range of
exterior wall thicknesses.
Example: If 20 feet total (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 verti-
cal rise except where an elbow is the only
vertical component in the system. See
Figure 44.