DuraVent Model BV Roof Top Termination Kit: four parts for both ends of your gas vent
The DuraVent Model BV Roof Top Termination Kit is a four part kit for a gas vent running straight up through the roof. You get the DuraCap for the top, adjustable roof flashing, a storm collar that fits around the pipe, and a draft hood connector for the appliance end. Pipe is not included. The flashing fits roof slopes from flat to 6 in 12. A steeper roof needs different flashing. Model BV is DuraVent’s Type B gas vent, the double wall pipe that carries the exhaust from a gas furnace, boiler, or water heater out of the house.
Choose a 3, 4, 5, or 6 inch size on this page. Vent diameter comes from the appliance instructions and fuel gas sizing tables, not from DuraVent. Buy pipe lengths, firestops, supports, and an attic shield separately. DuraVent requires at least 5 feet of vent above the appliance draft hood, with more height for a run with bends or two appliances. Only need the top cap? See the DuraVent Model BV DuraCap vent cap. The DuraVent Model BV Roof Top Termination Kit ships free from My Cozy Outdoors with No Sales Tax (except WY) and the full manufacturer warranty.
Details
SKU: 3BVK | 4BVK | 5BVK | 6BVK
Applications
Duravent’s Type B Gas Vent system. 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. Applications include: natural gas fireplaces, gas-fired furnaces, boilers, water heaters, and wall or space heating applications.
Materials and Construction
Round Type B Gas Vent 3″ – 8″ and Oval 4″ – 6″: Aluminum .012″ inner wall, galvanized .018″ outer wall, in Canada, the lengths have a galvalume .018″ outer wall. The 3″ – 8″ Round gas vent features DuraLock® and DuraTab® . The Oval gas vent features the button lock.
Round Type B Gas Vent 10″ – 18″: Aluminum .014″ inner wall, galvanized .018″ outer wall. DuraLock® feature for 10″ and larger diameters.
Round Type B Gas Vent 20″ – 30″: aluminum .023″ inner wall, galvanized .018″ outer wall. DuraLock® feature for 10″ and larger diameters.
Clearances
Clearances to combustible materials in single and multi-family dwellings:
- 1″ Clearance – USA – 3″ to 30″
- 1″ Clearance – Canada – 3″ to 24″
- 2″ Clearance – Canada – 26″ to 30″
Annular insulating air space
- 3″ – 8″ Round Vent: 1/4″ air space
- 4″ – 6″ Oval Vent: 1/4″ air space
- 10″ – 30″ Round Vent: 1/2″ air space
Diameters
- 3″- 30″ Round Diameter.
- 4″, 5″ and 6″ Oval (USA only)
Listings
UL Listed to UL 441 and CAN/ULC-S605 (MH2848 and MH17667).
FAQ
What is in the Model BV Roof Top Term Kit, and which size should I pick?
The kit includes a DuraCap, a flashing for flat to 6/12 roofs, a Storm Collar and a Draft Hood Connector; no pipe lengths. Pick the diameter (3, 4, 5 or 6 inch) on the selector above to match the appliance draft hood or flue collar; the 3-inch is the base listing and the larger sizes show their price there. Never size the vent smaller than the outlet.
Which appliances is Type B gas vent for?
Model BV is a Type B gas vent for natural gas or propane Category I and draft-hood-equipped appliances: gas furnaces, boilers, water heaters, wall or space heaters and gas fireplaces listed for Type B vent. It is not for wood stoves, pellet stoves or any appliance whose manual calls for a different vent type, so check the rating plate first.
What clearance to combustibles does Model BV need?
The 3 to 8 inch round vent is listed for 1 inch of air space to combustibles in the USA (1 inch in Canada up to 24 inch diameters). That air space must stay open: do not fill it with insulation, and use the firestop spacer at each ceiling and an Attic Insulation Shield in an attic to keep loose insulation off the pipe.
How tall does the vent have to be, and does this flashing fit my roof?
DuraVent requires at least 5 feet of vent height above the appliance draft hood, and more when the vent has an offset or serves more than one appliance, per the appliance instructions and the fuel gas code. The included flashing suits pitches from flat to 6/12; a steeper roof needs a different flashing. Any vent extending more than 5 feet above the roof must be guyed or braced.
How do the pieces connect?
Model BV lengths lock together with DuraVent’s DuraLock and DuraTab twist connection, so screws are not required on pipe joints. The Draft Hood Connector attaches to the appliance outlet with three sheet metal screws, the flashing nails to the roof with the upper flange under the roofing, and the Storm Collar is screwed to the pipe with the screw heads sealed with silicone.
What do I need where the vent passes through ceilings and the attic?
Every ceiling or floor the vent passes through must be firestopped with a Firestop Spacer or a Firestop Support Plate, which can also carry the vent’s weight. In an attic use an Attic Insulation Shield. Those parts are not in this kit, which covers only the roof-top termination and the appliance end, so add them with the Model BV pipe lengths.