Patterns initially are made in only one size. In order to produce clothing that fits various body types and sizes, the pattern pieces must be increased or decreased geometrically to create a complete range of sizes. The process of resizing the initial pattern is called “grading.” For example, the sample size 10 patterns must be made larger to accommodate sizes 12, 14 and 16 and smaller for sizes 8 and 6.
Pattern grading is the scaling of a pattern to a different size by implementing important points of the pattern using an algorithm in the clothing and footwear industry.
What is the purpose of grading clothing patterns? The purpose of grading is to proportionally increase or decrease the size of a pattern, while maintaining shape, fit, balance, and scale of the garment. Historically, the science of grading went hand-in-hand with the advent of commercial patterns and the mass-production of pattern-built clothing some 150 years ago. To properly fit a pattern to a range of sizes, each pattern piece needed to be graded, or systematically increased or decreased. Today, pattern companies and apparel manufacturers take a middle-sized pattern (for example size Medium) and grade it up for larger sizes and grade it down for smaller sizes.
Grading apparel has primarily three different methods that are often used in the fashion industry. Whether you want to take your favorite pattern up (or down) a size or two or if you want to create new collection of clothing, pattern grading is an important process. Once you understand the nuances, you’ll be able to take your sewing to the next level. With proper pattern grading techniques, a home sewer, custom dressmaker, novice, or professional fashion designer design incredibly well designed clothing.