Ease is the difference between the body measurements and the finished garment measurements.
There are two different types of ease: wearing ease, which allows movement and comfort, and design ease, which is added fullness for the purpose of design. Design ease is added over and above wearing ease.
There are two examples of wearing ease and one of design ease below two examples of wearing ease and one of design ease below.
The blocks and the grid in the three images below are to scale.
There are three examples; the Bodice Block, the Skirt Block and a skirt pattern.
Bodice Block Ease
This Bodice Block Size 12 is made for a figure with body measurements Bust 34 inches and Waist 26.5 inches. The actual block measurements are 38 inches in the Bust and 27.5 inches in the Waist; the orange shaded area is the approximate ease in the block.
The wearing ease that has been added is: 6 inches around the armhole, 4 inches in the bust, and 1 inch in the waist. Different areas of the body need different wearing ease.
Without this wearing ease, the garments would be too tight and restrictive. (Note: Less or minimal ease is needed with stretch clothing, but these are Standard Blocks not Stretch Blocks).
Skirt Block Ease
This is a Skirt Block set Size 12 made for body measurements: Hip 36 inches, and Waist 26.5 inches.
Wearing ease has been added so that the actual block measurements are; Hip 38 inches and Waist 27.5 inches. The approximate wearing ease is shown in orange. Remember that the blocks represent half the body, so the ease that is shown in on these blocks are half of the total ease on the garment.
See the image below for an A-line skirt that has been created with this block, but with extra design ease added on top of the wearing ease.
Skirt Pattern Ease
This A-line a skirt is made from the block in Image 2. It still has only 1 inch (wearing) ease in the waist, but a lot more ease has been added in the hips.
The hips are now about 48 inches inches, which is well above what is needed for comfort. This additional ease is Design Ease.
The outline of the original skirt block with only wearing ease is shown as a dashed blue line for comparison purposes.