When you are choosing the size to make for your pattern you will normally see this:
XS (S, M, L, 1X, 2X, 3X)
Finished chest measures: 85 (94, 104, 117, 124, 135, 145) cm/ 33.5 (37, 41, 46, 49, 53, 57)”
Upper arm circumference: 32 (32, 32, 36, 36, 40, 44, 49) cm / 12.5 (12.5, 12. 5, 14, 15.5, 17, 19)Finished length from underarm: 30 cm/ 12”
Designed to be worn with an ease of 5–8 cm/ 2-3”
So which size should you choose?
For example: You have a 39″ chest, the garment suggests adding 2-3″ which gives you 41″ or 42″ so you would make the size M because that has a finished measurement of 41″
If the garment above were suggesting it was worn with a negative ease of 1-2″ then you would subtract it (because you are adding a negative number) giving you 38″ or 37″ so you would make the size small because that has a finished measurement of 37″.
But why not just make the size closest to your actual measurement?
Ease is the amount of give in a garment – probably almost none of the clothes in your wardrobe will have the same chest measurement as you. You add the ease to your measurement to give the finished size you will want to wear.
If you are working from a pattern, the designer will have considered ease – if you wish to alter the pattern or design your own you will need to think about how much ease to allow.
There are two types of ease that designers consider when creating a design – functional ease and design ease.
Functional ease is about allowing enough room for the garment to be wearable. Can the head fit through the neck hole, can you move your arms. Luckily with knit wear this tends to be less problematic than with our sewing friends as knitted (and to a lesser extent crocheted) fabric has stretch that woven fabrics don’t. However as we are often creating items that are designed to be overlayers the functional ease often needs to allow for garments to be worn underneath. It is also really important for hats where a little negative ease is needed at the brim otherwise the damn thing won’t stay on! (too tight and you’ll have a massive headache!)
Design ease is about how it looks and drapes and this is more to do with style, fashions and personal preference.
Both functional ease and design ease requirements are affected by the type of fabric we are making so consider carefully how stiff or drapey and how elastic the fabric you are producing is. The thickness of the fabric is also an important consideration as the finished measurement of the inside of a very thick sweater will be less than the external measurement by twice the thickness. Therefore the fibre content and weight of the yarn and the tension/gauge you are working at will all affect the ease needed.
Obviously when we talk in terms ease we often use inches but 2″ of ease on a 60″ chest will give a different effect to 2″ ease on a 30″ chest so it may be helpful to also think about it in terms of percentages if you are larger. (working in inches is probably going to be okay if you are XS-L)
Percentages are also useful when we are considering ease at points other than the chest. We normally use the chest measure for setting the size as often that is the most important fit point but for a well fitting garment that you will enjoy to wear it is important to take some time to consider whether the ease is correct at the upper arm, the waist and the hips too.
As a rule of thumb:
|inches ease||cm ease||% ease||type of fit|
|-2 to 0||-5 to 0||-5 to 0||tight|
|0 to 2||0 to 5||0 to 5||slim|
|2 to 4||5 to 10||5 to 10||regular|
|4 or more||10 or more||10 or more||baggy|
But what does this actually look like on? I have a 40″ chest and took a tape measure to my wardrobe to find examples in each size then I braved the camera to model t-shirts with varying degrees of ease.
|+4″ ease (44″) 10%|
|+2″ ease (42″) 5%|