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. 

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.