3.3
SPECIAL VENT INSTALLATIONS
3.3.1 PERISCOPE TERMINATION
Use the periscope kit to locate the air termination above grade. The periscope must be installed so that
when fi nal grading is completed, the bottom air slot is located a minimum 12" (30.5cm) above grade.
The maximum allowable vent length is 10' (3.1m).
30" (76.2cm)
MIN
24 1/4"
(61.6cm)
3.3.2 CORNER TERMINATION
The maximum vent length for a corner installation is 20" (50.8cm) of horizontal run, in addition to the 45°
offset. In this case zero rise is acceptable when using rigid venting. It is required to maintain a 6"(15.2cm) rise
when using fl exible venting. See illustrations below.
12" (30.5cm)
MIN TO
GRADE
6" (152.4mm)
RISE MINIMUM
FLEXIBLE VENTING
30"
(76.2cm)
MIN
34"
(86.4cm)
9.4B
20" (50.8cm)
MAXIMUM
RIGID VENTING
11
EN
12" (30.5cm)
MIN TO
GRADE
W415-1516 / B / 02.15.17