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ADI Ductulator – Duct Size Calculator

4.7 (2) Write Review
Free shipping on orders over $29.99

$15.99

$ 7 .99 $7.99

In Stock
  • The ADI Ductulator was created by the Air Distribution Institute based on research conducted by a prestigous university to study the effect of compression in flexible duct on air flow efficiency.
  • The data provided on the ADI Ductulator shows research data obtained with flexible duct compressed 4%, 15% and 30% in length. These compressions, and others, were studied because flexible duct is typically not installed “fully stretched” and the resulting installation causes greater pressure loss and is far less efficient in air flow distribution.
  • Typical installations are not in a straight line on a flat surface. The kinks, bends, sharp turns and sags of the typical installation increase pressure loss even more than represented by the ADI Ductulators data.
  • Using the ADI Ductulator will help you choose the correct size flexible duct to overcome any adverse effects on pressure loss due to the compression and achieve proper CFM and FPM air flow.
  • Along with the duct size calculator found on the front of the ADI Ductulator, you’ll find charts with commonly used fittings and other connectors on the back.


The ADI - Air Distribution Institute, was formed in 1947 to promote the use of fabricated steel duct pipe and fittings for air distribution products. Today the alliance of ADI member companies produce steel duct pipe and fittings designed to efficiently deliver conditioned air in your home and office. ADI sponsors independent third party research to accurately substantiate the superior benefits of Steel Air Distribution Systems. Get your ADI Ductulator today!


Chris Van Rite
Reviewed in the United States on March 3, 2025
This is the most complete Duct Size Calculator available, other than the ASHRAE version.It gives equivalent sizes for any combination of CFM, Velocity and Friction Loss in Round and Rectangular Sheet Metal Duct as well as Flexible Duct at three different compression installations.It is also the only Duct Size Calculator approved for use in the Texas State HVAC License Exam.
Megan
Reviewed in the United States on February 26, 2025
Best ductulator on the market!
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