Pattern Block

Definition and Overview

A pattern block is a foundational pattern that shows the basic shapes and reference lines for the bodice, sleeves, and other parts. It is created based on body measurements such as the bust, waist, and hips, along with the ease required for wear, and is developed into product patterns by adding darts, seam lines, gathers, and other details according to the design.

A block is not the finished garment pattern itself, but the starting point for design. Because the finished silhouette changes depending on the block’s size settings, ease, and drafting method, it is important to use a modified block suited to the brand and target wearer.

Parts Used and Their Roles

In general, the front bodice block, back bodice block, and sleeve block are used as the basics. As needed, blocks for skirts, pants, and collars are also used. A bodice block includes standards for fitting a three-dimensional body, such as the shoulder line, side seam, bust and back darts, and the front and back center lines.

Pattern makers use the block to consider the distribution of ease, dart manipulation, seam positions, and changes in length and width. In this way, they translate design intent into a flat pattern and adjust it so that after sewing it has the intended three-dimensional shape and wearing comfort.

• For tops, the bodice and sleeves are the main focus.
• For skirts, the shape from the waist to the hips is the standard.
• For pants, the balance of the waist, hips, crotch, and leg area is the standard.

Materials and Types

Pattern blocks are stored and drafted on paper, and are also managed as thick paper or digital data. In sampling, the pattern pieces developed from the block are used to cut sheeting or other trial-sewing fabric to check the shape and ease. The block itself is not a material used in garments.

Types vary by target gender, age group, body type, and item. The required ease and handling of stretch differ between woven and knit fabrics, so even the same design cannot always use a common block as is. The term Bunka block is used as the name for a block based on the Bunka drafting system.

Main Applications

Pattern blocks are used in the pattern design of shirts, blouses, jackets, dresses, skirts, pants, and more. In the planning stage, they are used to examine silhouettes; in the sampling stage, they are used for fitting with toile samples; and before mass production, they form the basis for finalizing specifications and measurements.

In draping, fabric is placed on a dress form to create the shape, and then that shape is transferred to a flat pattern and checked against the block or pattern. Using both flat drafting and draping makes it easier to confirm the design measurements and the actual three-dimensional appearance.

How to Choose, Handle, and Sew

Choose a block that matches the intended wearer’s body type, the planned item, the fabric’s stretch, and the desired silhouette. Even a standard block for ready-made clothing must be adjusted through sampling and wear testing to match the brand’s own size standards and fit.

When making a toile with sheet material, align the grainline correctly with the block’s reference lines and transfer notches and dart positions accurately. Misaligned grainlines and inconsistent seam allowances can lead to twisting and dimensional errors when worn. The shrinkage rate, thickness, stretch, and drape of the actual fabric used are also reflected in the production pattern.

Differences from Similar Terms

A pattern refers broadly to the cutting pattern with design details, specifications, seam allowances, notches, and the like added on the basis of the block. In contrast, a pattern block is the basic form used to develop multiple designs.

A toile is a sample made by temporary stitching to check the shape and fit of a pattern, or the sampling process itself. The block is a design standard, while the toile is a three-dimensional sample used to verify the pattern developed from the block.

Frequently Asked Questions