DuraVent Type B Venting Installation Guide
Simpson Dura-Vent's Type B Gas Vent system is for use with natural gas or liquid propane category I and draft hood equipped appliances, and appliances tested and listed to use Type B Gas Vent for a wide range of applications, including: natural gas fireplaces,
gas-fired furnaces, boilers, water heaters, and wall or space heating applications.
Simpson Dura-Vent's Type B Gas Vent systems are UL Listed to UL 441 and UL 1777 (MH6357). ULC Listed to ULC S605 (CMH1276 & CMH1407).
Refer to the Typical Installation drawings below to select
the appropriate component parts for your installation.
 
 
How Size and Height
Affect Stove Performance
The amount of heat the vent gases lose as they flow determines
how much condensation will occur and how strong the draft will be. To control
the heat loses, proper selection of venting materials is of vital importance.
Double-wall Type B Gas Vent, with an aluminum inner wall and a
galvanized steel outer wall, has proven to be the ideal choice in venting
materials.
A Type
B Gas Vent Sizing Handbook is available to assist you with the proper
installation. Click HERE
to view online.
Vent Termination Chart
Using listed Type B Gas Vent caps may terminate in accordance
with this table.
Gas Vent Specification
Chart
NOTES
1. Clearance to combustibles is the air space between vent and
combustibles.
2. Maximum height varies with equipment over 50’, for taller applications refer to SDV sizing handbook 2. (L202). 14"-16" Require screws.
3. When oval is used on wall furnaces, minimum height required from bottom of furnce to cap is 12’, minimum 16” stud space.
4. Limited by sizing tables.
5. 18” pipe OD is one inch larger than ID and 20” - 30” OD is 2” greater than ID.
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