DuraVent 100' Flex Pipe DuraFlex SW Stainless Steel Length

Size: 5.5"

Estimated Arrival: Between and . (To All Contiguous States)

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DuraVent is the premier company in the venting industry. With a broad range of engineered venting products, DuraVent has earned its reputation as the industry leader by offering innovative, safe, and professional products for the HVAC and Hearth markets.

DuraFlex SW is a smooth inner-wall, flexible stainless steel chimney liner. The smooth inner wall provides no output reduction allowing for total appliance efficiency. Smooth wall construction eliminates ridges that restrict flue gas flow and collect deposits. The lack of ridges facilitates cleaning and maintenance. DuraFlex SW is ideal for relining masonry chimneys for wood and gas-burning appliances. Listed to UL 1777.

Customize The Flex You Need

All DuraFlex is available for orders requiring custom lengths (minimum 10' length). DuraFlex Pro and DuraFlex SW also offer 9"-12" diameters when ordered in custom lengths. (minimum 10' length). Use Ventinox components for all 9"-12" flex systems.



  • Custom lengths are also available for 3” - 8” diameters. 9”-12” diameters available in custom lengths only (Use Ventinox components).
  • Minimum length of 10’ for custom orders.
  • Maximum 200' for 3" - 4" diameters, 125' for 5" diameter, 100' for 5.5" - 6", 50' for 7" - 8", 25' for 10" and 12" diameters.


  • Must be ordered in increments of 10'.
  • 3"-8" diameter flex can be ovalized up to the first 4'.
  • Call Customer Service to add ovalizing to your order and for pricing.



DuraFlex SW smooth wall flexible relining for a masonry chimney. Use with gas, wood pellet, oil, or wood appliances. Applications include: fireplace inserts, furnaces, boilers, and water heaters



Model Size Flex Length
55DFSW-100 5.5" I.D 100 ft.
6DFSW-100 6" I.D 100 ft.
Construction Single-Wall
Clearance 0” clearance for gas, oil, and pellet applications.
Clearance 1” clearance to masonry for wood-burning
Listings Listed to UL 1777 and ULC S635 (MH45609).
Warranty Limited lifetime warranty




Safety Information: CA Prop 65 Warning