Our stacks have an engineered laminate schedule manufactured to precise standards ensuring consistency
and excellent quality. Each stack has a belled inlet and conical, diverging exit for reduced air pressure drop losses and pressure recovery for high fan efficiency. Fan stack sections are connected via lap joints or butt flange allowing field adjustment of the stack diameter and control of fan blade tip clearance maximizing fan performance. The fan stacks are secured to the structure by through bolts attached to deck joists. Each stack has a removable access panel opening for maintenance on the fans and gears. As part of our ISO quality system each part is given a unique serial number and is tracked throughout the manufacturing process, with quality checks at every step.


• The diameter of the fan stack is based on the diameter of the fan
• All fan stacks have an elliptical flair
• Typical heights of the fan stacks are 6’, 8’, 10’, 14’ and 18’
• Standard nominal 20 mil. gray gelcoat color
• Class III with a flame spread of 75’ or greater
• Typical cross sectional laminate 3/16”
• Molded utilizing pre-formed channel rib construction
• Perimeter bolting flanges are reinforced with layers of woven roving
• Perimeter cross sectional laminate is 3/8”
• 304 Assembly Hardware

optional features

• Class I with a flame spread of 25’ or less
• Class II with a flame spread of 50’ or less
• Special sizes available
• Reinforced throat sections
• Extensive selection of resin types and color matching gelcoat colors available
•  Shaft Coupling Guards
• View Ports
•  Access Doors
•  Stiffener Rings
•  316 Assembly Hardware


If one of our standard fan stacks do not meet your needs, we can custom build a mold or customize your products to whatever specific needs you may have.