Using an hvac duct sizing calculator.
Hvac ductwork weight calculator.
Because of this hvac professionals and amateurs alike typically don t calculate the final hvac ducting size by themselves.
This calculator is designed to give the approximate weight of sheet metal based on length width and thickness.
Your overall ducting size comes from combining the size cfm and friction loss of your home meaning it ends up being a pretty complicated calculation.
A round duct with a cross sectional area of 0 6m2 has a perimeter of 2 75m a rectangular duct with an equal cross sectional area has a perimeter of 3 87m the rectangular duct therefore requires more metal for its construction this adds more weight and costs to the design.
Find the area of duct first for example duct size is2 x3 and length 10 find area 2 3 x2 x10 100 sq ft 100 3 28x3 28 sq meter 9 3 sq meter if.