Woven fabric consumption formula for textile eng

How can measurement  Apparel Merchandising, for Fashion design.
Before calculate the woven fabric consumption, you must need the followings information as mentioned step by step-:

1) Measurement chart with technical spec.
2) Style Description.
3) Fabric Description.
4) Fabrics width/weight.
5) Washing shrinkage if any.
6)

This formula is as under :
Formula = Length  X Width  / Fab width X Fab Unit


Here,
Length = length of the specific parts + allowance

Width  = width  of the specific parts + allowance

Fab width = Fabric width ( after considering the shrinkage
                    allowance).
                   Say, fabric width is 45" & the shrinkage
                   allowance is 1", Then the Fabric width will
                   be (45"-1") = 44" in the formula.

Fab unit = Fabric calculation unit, here it will be 36 because
                we are going to calculate the consumption in
                Yards.


Now we will calculate the consumption of a Shirt (front part)

Center front length  = 32"+1" (Sewing allowance) = 33"
Width (Chest)        = 24" + 1" (Sewing allowance) + 3"
                                 Pleat.W (1.5X2)  = 28"


= Length  X Width  / Fab width X Fab Unit
= 33" X 28" /  44" X 36"
= 924" / 1584"
= 0.5833333

= 0.59 Yards. (for front part)