DuraLiner® ensures safe and efficient venting of heating appliances, while protecting the masonry chimney from the damaging effects of flue gas. It is the only factory-insulated product with zero/zero clearance for high heat wood-burning appliances. No need to uncoil flex, insulate a majority of the pipe, or protect the insulation when installing. A smooth inner means less creosote buildup.

Installers reduce labor time by 50% or more with DuraLiner. No time wasted wrapping insulation around liner for UL 1777 approval.

No spacers needed to maintain clearance in tight offsets or dampers. Approved for use in both the USA and in Canada. 

DuraLiner is a high-temperature, insulated double-wall masonry relining system for use with appliances fueled by gas, pellet, oil, wood, or coal. It safely protects masonry chimneys from the damaging effects of flue product condensation.

Materials and Construction
.016″ 304 stainless steel inner liner. Rigid relining pipe: double-walled with 304 stainless steel inner and galvalume outer. Factory insulated between inner and outer walls. DuraLiner Rigid Pipe in round or oval, is constructed with built-in fittings and pre-drilled holes (stainless steel rivets included). Round 5″ DuraLiner rigid pipe is constructed with built-in twist-lock and pre-drilled holes.

Rigid double wall: 0″ clearance between the liner and masonry and 0″ clearance between the masonry and combustibles. DuraLiner Flex: 1″ clearance to masonry. Zero clearance with insulation.

5 “, 6″ and 8”

UL Listed to UL 1777 (MH14420), ULC Listed to ULC S635 .

Refer to our Typical Installation drawings to select the appropriate component parts for your installation

  • The inner pipe diameter should match the outlet size of the appliance.
  • Check the appliance manufacturer’s installation instructions for any venting restrictions.
  • Be fire safe! Follow local building codes and have your venting system inspected.


More Typical Installations:

Installation Key
1Extend-A-Cap Kit
2Round Tee with Round Branch
3DuraTech or DuraPlus Chimney
4Tee with Removeable Snout
5DuraLiner – flexible length
6Masonry Thimble w/ Slip Connector
7Slip Connector and Hanger
830° or 45° SS Elbow
9Transition Anchor Plate
10ProMesh & ProFoil
11Insulation Clamp
12DuraLiner Appliance Connector
13DVL or DuraBlack Stovepipe

Planning Your Installation:

1Refer to the Typical Installations for the needed parts for installation.
2The size of the liner should match the outlet size on the appliance.
3Determine use of round or oval pipe based onthe interior shape of the chimney
4Determine the length of liner needed. Subtract 1 1/2″ overlap per joint on pipe. When using Extend-A-Cap kit, liner must extend 6″ above top of the masonry surface.
5Make sure the top of the masonry chimney has a leveled surface to insure a proper fit for the Extend-A-Cap or Transition Anchor Plate and to provide a secure, leak-proof installation.
6If a free-standing appliance is used, select the vent or stovepipe pieces to connect from the appliance to the liner. Refer to installation instructions.
7For Installations using a Transition Anchor Plate, refer to the DuraTech, DuraPlus, or DuraPlus HTC catalog section or installation instructions for proper parts and installation.
8Important! Check to be sure the installation complies with all local and national code requirements, including clearance to combustibles. Contact the local building inspector for permit requirements.

Design Recommendations

  • The following design recommendations are a general guideline to assist in the design and selection of liner components for your installation. Always follow DuraVent installation instructions enclosed with the cap or support box before installing your chimney system.
  • Before relining a chimney, it should be cleaned and inspected, by a certified chimney sweep, to verify the integrity of the mortar and masonry.
  • DuraLiner is approved for 0″ clearance between the liner and masonry and 0″ clearance between the masonry and combustibles.
  • DuraLiner is used for wood-burning appliances when zeroclearance or oval pipe is needed.
  • Refer to the appliance manufacturer for installation requirements affecting venting. Keep the vent path as straight as possible for best performance.

Restore Deteriorating Chimneys with DuraLiner
When a masonry chimney is damaged or has fallen down, it can be replaced with a safe, listed liner system or factory-built chimney. DuraLiner, when used with a Transition Anchor Plate and in combination with DuraTech, DuraPlus, or DuraPlus HTC Chimneys, replaces the damaged masonry chimney with a safe, efficient, and economical listed chimney system (DuraPlus HTC is listed for use in Canada). See Typical Installations for details.