Notes:
•It is very important that the horizontal/in- clined run be maintained in a straight (no dips) and recommended to be in a slightly elevated plane, in a direction away from the fireplace of 1/4" rise per foot (20 mm per meter) which is ideal, though rise per foot run ratios that are smaller are acceptable all the way down to at or near level.
•SV4.5VF (Secure Vent), SF4.5VF (Secure Flex) firestop/spacer must be used anytime vent pipe passes through a combustible floor or ceiling. SV4.5HF (Secure Vent), SF4.5HF (Secure Flex)firestop/spacer must be used anytime vent pipe passes through a combustible wall.
•Two 45 degree elbows may be used in place of one 90 degree elbow. The same rise to run ratios, as shown in the venting Figures for 90 elbows, must be followed if 45 degree elbows are used.
•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).
uCeiling Firestop / | 40 feet | |
(12.2 meters) | ||
Spacer (SV4.5VF) | ||
Maximum | ||
|
uWhen using Secure Flex, use Firestop / Spacer
SF4.5VF
A Vent Restrictor, as shown in Figure 18 Page 11, must be used in this application
Figure 28 - Top Vent - STRAIGHT
Table A
H Maximum | V Minimum | ||
feet | (meter) | feet | (meter) |
|
|
|
|
2 | (0.610) | 1 | (0.305) |
|
|
|
|
4 | (1.219) | 2 | (0.610) |
6 | (1.829) | 3 | (0.914) |
|
|
|
|
8 | (2.438) | 4 | (1.219) |
|
|
|
|
V + H = 40 feet (12.2 meters) Max.
H = 8 feet (2.4 meters) Max.
Ratio V to H ratio is 1:2
Example: If 8 feet of (H) horizontal vent run is needed, then 4 feet minimum (V) vertical vent will be required.
This table shows a 1(V) to 2(H) ratio. For every 1 foot of (V) vertical, you are allowed 2 feet of (H) horizontal run, up to a maximum horizontal run of 8 feet.
uWhen using Secure Flex, use Firestop /
Spacer SF4.5VF.
uCeiling Firestop /
Spacer (SV4.5VF)
V
H
Figure 29 - Rear Vent - ONE 90 DEGREE ELBOW
H
uCeiling Firestop /
Spacer (SV4.5VF)
V1
Table B
H 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) |
V + V1 + H = 40 feet (12.2 m) Max.
H = 20 feet (6.096 meters) Max.
V
Example: If 20 feet of (H) horizontal vent run is needed, then 4 feet minimum of (V) vertical vent will be required.
vWall Firestop/ | This table shows a 1(V) to 5(H) ratio. For | |
every 1 foot of (V) vertical, you are allowed 5 | ||
Spacer (SV4.5HF) | ||
feet of (H) horizontal run, up to a maximum | ||
| ||
| horizontal run of 20 feet. | |
uWhen using Secure Flex, use Firestop / | An elbow is acceptable as 1 foot of vertical | |
Spacer SF4.5VF. | rise except where an elbow is the only vertical | |
vWhen using Secure Flex, use Firestop / | component in the system. See Figure 37. | |
Spacer SF4.5HF. |
|
Figure 30 - Top Vent - TWO 90 DEGREE ELBOWS
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
15
