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Get it between 2025-08-12 to 2025-08-19. Additional 3 business days for provincial shipping.
Versatile HVAC Calculator: Sizes supply and return duct systems using equal friction or velocity reduction design method
Dual-Sided Design: Front features scales for various duct sizes and properties, while the back offers fitting equivalents, pressure drop charts, and HVAC formulas
Durable Construction: Made of thick, water-resistant paper stock with glued edges and corner rivets for long-lasting use
Practical Reference Guide: Includes recommended duct velocities, gauges for sheet metal, and other essential HVAC data
Compact and Portable: Measures 4 inches high and 8.5 inches wide, fitting easily into tool belts or bags for on-the-go use
The Duct Sizing Calculator is a hand held sliding calculator used for sizing supply and return duct systems using the equal friction, or velocity reduction design method. Front of calculator includes scales for friction, velocity, round duct size, weight per linear foot of round duct, surface area in square feet per lineal foot of round duct, rectangular equivalents of round duct sizes, weight per linear foot of rectangular duct and surface area in square feet per linear foot of Rectangular duct. Back of calculator has equivalent feet of straight duct for commonly used fittings, corrected pressure drop chart, and many HVAC formulas. Pull out slide has recommended duct velocities, recommended gauges for sheet metal, and much more. The photo shows front side of the tool. This slide is made of thick durable water resistant paper stock with glued edges and corner rivets. Tool measures 4 inches high and 8.5 inches wide. Picture shows front and back.