How to calculate Fabric consumption

Lets calculate the fabric consumption of a basic T-Shirt: 

 

 

Here,

1/2 chest =53 cm

Sleeve length (SL) = 18 cm

Center length (CL) = 69 cm

G.S.M = 145

Calculation: 

{(SL+CL+10) * (1/2 chest) * 2 * 12 * G.S.M} / (100 * 100 * 1000)

= {(18cm + 69cm + 10cm) * (53 cm) * 2 * 12 * 145} / 10000000

= 1.789068 Kg/Dz

Adding rib: We add 5% for regular T-shirt & 7% for kids T-shirt

= 1.789068 + 5%

= 1.8785214 Kg/Dz

Adding 13% Wastage:

= 1.8785214 + 13%

= 2.122729182 Kg/Dz

 So we need 2.122729182 Kg of fabric for making 12 pieces (Dz) of T-shirt.

Formula Analysis:

{(SL+CL+10) * (1/2 chest) * 2 * 12 * G.S.M} / (100 * 100 * 1000)

• Here 10cm is total sewing allowance. (2.5cm + 2.5cm at two sleeve. And 5cm at bottom) 
• We are multiplying 2 because we have back part & front part of the body. 
• We calculate the fabric consumption for 12 piece. So we are multiplying 12.
• First 100 is for making the length in miter. Because G.S.M is always in miter.
• And similarly 2nd 100 is for getting the width in miter.
• Finally 1000 is for getting the result in Kg. Because we have weight (G.S.M) in gm.  

If you have any question about this calculation please comment.