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DuraStack® Pro

DuraStack Pro

Note: Available through Exclusive Representation only, please contact your Commercial Sales Manager for more information.

The DuraStack Pro Series, Models DCL, DAS1, DIS1, DIS2, DIS4, DIS3Z venting systems, are designed to offer the ultimate in installation convenience and versatility for a variety of applications. Certified for commercial chimney and diesel exhaust applications, they are constructed of thick-gauge material for the inner pipe that provides a strong and rigid assembly. Featuring a self-centering flue extension design that significantly simplifies and accelerates the installation process.

Available in sizes from 5" to 36" diameters, the DIS line offers double-wall configuration with a choice of 1", 2", 4" or 3" insulation and the DAS line offers a 1" air insulated product. For premium corrosion resistance and durability, the inner flue is constructed from 0.035" thick Stainless Steel 304 or 316 Stainless Steel. This is coupled with a 0.024" thick 304 Stainless Steel or Galvalume (Aluminum-zinc coated) steel outer casing. The DIS line features the highest-quality insulation, densely packed to ensure low heat loss and maximum draft.

  • Specifications
  • Typical Installation
  • Literature

DuraStack Pro is available in the following configuration.
DCL: Single Wall
DAS1: 1" Air Insulated
DIS1: 1" Insulated
DIS2: 2" insulated
DIS4: 4" Insulated
DIS3Z: 3" Insulated
Applications include: Low and High-Pressure Steam Boilers; Diesel and Turbine Exhaust; Building Heating Equipment. Industrial Furnaces; Processing Equipment; Kilns and Ovens; Grease Duct.

Materials and Construction
Inner Wall Material Thickness
5" - 18" .035" Laser welded, 304 or 316
20" - 36" .035" Plasma welded, 304 or 316

Outer Wall Material Thickness
5"- 12" .024" Laser welded, 304, Galvalume
14"- 36" .024" Pittsburg Lock, 304, Galvalume




UL 103 – Building Heating Appliance

UL 103 (HT) – Standard for Factory-Built chimneys for residential type and building heating appliances

UL 1978 – Standard for Grease Ducts

UL 2221 – Standard for tests of fire resistive Grease Duct enclosure assemblies. DIS3Z only

UL 2561 – Standard for 1400°F Factory- Built Chimneys. Excludes DIS3Z

UL 1777 – Standard for Chimney Liners. DCL only


ULC/ORD C959 – Chimneys, Industrial 540°C and 760°C

ULC S604 – Standard for Factory-Built Type A chimneys

ULC S662 – Standard for Factory-Built Grease Duct

ULC S635 – Standard for lining systems for existing masonry or Factory-Built chimneys and vents.

Typical installation for Diesel Generator Exhaust


Typical Installation for Boiler Application

         Grease Duct Installation Drawing