Drafting the Sleeve Block
Sleeves – General Information

Ease in the Bicep
For the standard figure 2 inches ease in the bicep is usually sufficient. This ease is not only for bicep itself, but also to allow movement of the arm so you can reach forward without constriction. The amount of ease in the bicep also affects the fit across the upper arm.
Some people may actually end up with a sleeve that has sufficient ease for the bicep (i.e. it is fine in the bicep when you are standing with your arms at your side), but they cannot stretch both arms forward without constriction, or maybe even pain. In this case, they need to add more ease to the bicep to get the freedom of movement for the arms.
Adding more ease to the bicep is not, in and of itself, a problem. You should to add as much ease as necessary (4 inches should be sufficient) for a comfortable sleeve. The only issue you will run into is that you will not get the Ideal Fitted Sleeve in the one-piece sleeve block. You will probably end up with more ease in the sleeve cap than is ideal. That is just aesthetics; you can always put in dart or a seam-line and remove the excess. You can keep the minimal ease in the sleeve cap by having a lower Cap Height; which will not be a problem if you have sufficient ease in the bicep. (A Low Cap Height is a problem when you have very minimal ease in the bicep). What it will mean is your sleeve will be less fitting.
Below is a brief attempt to explain this quickly, but the same information can be found in more detail in the articles on Understanding the Sleeve.
So How Much Ease Should I Add?
This is my suggestion:
- If you have a Standard Figure as far sleeves go; i.e. shop purchased shirts and tops made of woven fabric (not stretch) generally fit well, and there is no constriction in the sleeve, either when standing still or when reaching forward, use 2 inches ease.
- If you generally find sleeves on purchased shirts and tops made of woven fabrics (not stretch) uncomfortable and constrictive; either when standing still, or when reaching forward, use 4 inches ease.
- The ideal ease may be somewhere in between, so you could start with two and determine how much extra to add…. that is up to you.
- Four inches ease should be enough for more people.
What is the ideal (one-piece) fitted sleeve?
- It follows the curve of the arm, rather than flaring away from the arm
- It has minimal ease in the bicep; this minimal amount you need for a comfortable garment that allows movement
- It has minimal ease in the sleeve cap; just enough ease to sew the sleeve into the bodice, without gathers or tucks
Why can’t you have the ideal fitted sleeve?
Sometimes, in order to achieve the first two points above, means you can’t achieve the third point. This means you will end up with gathers or tucks in the sleeve-head. Again, this is not a problem in and of itself, it just means that in order to have a sleeve that looks fitted (doesn’t flare away from the arm) and has enough ease for movement, you will have excess ease, in the form of gathers and tucks, in the curve of the sleeve.
Having said that, you could create some darts to get rid of the excess ease,or put a seam line down the middle and remove the excess at the shoulder point by making the seam line curved. It then becomes a two-piece sleeve.
So to reiterate: you sometimes can’t get all three of the ideals in a 1-piece sleeve block, unless you put in some darts.
Who will have this problem?
- If you have a bicep that is disproportionately larger than the rest of your body*.
- If you have other Fitting Issues such as a rounded upper back and forward sloping shoulders
The Bottom Line
If you have a larger bicep than normal, using your bicep measurement (and adding ease) will be the first step to getting a better fitting sleeve, but whether or not you need to add more than 2 inches ease is something you need to figure out by making a toile and checking it out. Make sure when you put on the toile that you reach both arms forward, and back, and up, etc.. rather than just standing normally. Unless you also have a disproportionately small Cap Height, you will end up with excess ease in the sleeve cap.
If your biceps seem to be in the ‘normal’ range, but you have other fitting issues, you may need more than 2 inches ease in the bicep. Again, once you have made your toile, make sure you try moving your arms in all the ways you would in the course of a day, and see if there is any tightness and constriction. If there is, you will need to work out how much extra ease you need. You will also end up with excess ease in the sleeve cap.
In both of the cases above, if you would prefer the sleeve cap to have the minimal ease, you could reduce the Cap Height, and have a more Flared Sleeve rather than a Fitted Sleeve. This means (obviously) that your Fitted Sleeve won’t be very Fitted. But then…. how fitted does a fitted sleeve have to be, to be a fitted sleeve?
Examples
The two images below show where there may be insufficient ease to allow arm movement, even though there is sufficient ease for the bicep itself. You can also see the ramifications for the amount of ease in the sleeve cap.
Image 1: Insufficient Ease
- The brown sleeve has the correct Cap Height for a fitted look and a bicep measurement that is sufficient for the bicep itself, but there is insufficient ease for arm movement, as shown.
- The yellow sleeve has the correct bicep measurement to allow the full range of movement necessary. There is minimum ease in the sleeve head, which means there will not be any gathers. However, the low Cap Height (needed for to achieve minimum ease in the sleeve cap) means that the sleeve isn’t really the ideal fitted sleeve; it will flare away from the body.
- The dashed black line shows what will happen if the correct Cap Height and the correct Bicep measurement is used. You can see that the length of this line will be significantly more than either of the other two. This means there will be excess ease in the sleeve cap, which will result in gathers or tucks.

Image 2: Insufficient Ease
- The brown sleeve has the correct Cap Height for a fitted look and a bicep measurement that is sufficient for the bicep itself, but there is insufficient ease for arm movement, as shown.
- The yellow sleeve has the correct bicep measurement to allow the full range of movement necessary. There is minimum ease in the sleeve head, which means there will not be any gathers. However, the low Cap Height means that the sleeve isn’t really the ideal fitted sleeve; it will flare away from the body.
- The dashed black line shows what will happen if the correct Cap Height and the correct Bicep measurement is used. You can see that the length of this line will be significantly more than either of the other two. This means there will be excess ease in the sleeve cap, which will result in gathers or tucks.

Sleeve Cap Ease
You will need to refer to this table while making your Sleeve Block.
- How much to add to the Armhole measurements to gain required Sleeve Cap Ease (Instructions in Image 2)
- Length of Dart Leg (Instructions in Image 7).
Sleeve Cap Ease & Elbow Dart Length
Bicep Measurement | Add to Armhole MM (Image 2) | Dart Leg (Image 7) |
---|---|---|
9.5 inches | 0.5 inches | 3 inches |
9.75 inches | 0.5 inches | 3 inches |
10 inches | 0.7 inches | 3 inches |
10.38 inches | 0.7 inches | 3 inches |
10.88 inches | 0.7 inches | 3.25 inches |
11.38 inches | 0.8 inches | 3.38 inches |
11.88 inches | 0.8 inches | 3.75 inches |
12.38 inches | 0.8 inches | 3.75 inches |
12.88 inches | 0.8 inches | 4 inches |
Download these measurements for following along with the instructions: Measurements-Instructions-Sleeve (1 page PDF file).
Fitted Sleeve Issues
This is a summary of the content in the articles on Understanding the Sleeve.
What is the Ideal (one-piece) Fitted Sleeve?
- It follows the curve of the arm, rather than flaring away from the arm
- It has minimal ease in the bicep; this minimal amount you need for a comfortable garment that allows movement
- It has minimal ease in the sleeve cap; just enough ease to sew the sleeve into the bodice, without gathers or tucks
Not everyone can have the ideal Fitted Sleeve
Sometimes, in order to achieve the first two points above, means you can’t achieve the third point. This means you will end up with gathers or tucks in the sleeve-head. Again, this is not a problem in and of itself, it just means that in order to have a sleeve that looks fitted (doesn’t flare away from the arm) and has enough ease for movement, you will have excess ease, in the form of gathers and tucks, in the curve of the sleeve.
Having said that, you could create some darts to get rid of the excess ease,or put a seam line down the middle and remove the excess at the shoulder point by making the seam line curved. It then becomes a two-piece sleeve.
So to reiterate: you sometimes can’t get all three of the ideals in a one-piece sleeve block, unless you put in some darts.
Who will have this problem?
- If you have a bicep that is disproportionately larger than the rest of your body*.
- If you have other Fitting Issues such as a rounded upper back and forward sloping shoulders
*Here is a (rough) guide to some standard (Australian) bicep measurements, and what I deduced Vogue patterns use for their bicep measurements.
The Bottom Line
If you have a larger bicep than normal, using your bicep measurement (and adding ease) will be the first step to getting a better fitting sleeve, but whether or not you need to add more than 2 inches ease is something you need to figure out by making a toile and checking it out. Make sure when you put on the toile that you reach both arms forward, and back, and up, etc.. rather than just standing normally. If you add more than 2-inches ease in the bicep, unless you also have a disproportionately small Cap Height, you will end up with excess ease in the sleeve cap.
If your biceps seem to be in the ‘normal’ range, but you have other fitting issues, you may need more than 2 inches ease in the bicep. Again, once you have made your toile, make sure you try moving your arms in all the ways you would in the course of a day, and see if there is any tightness and constriction. If there is, you will need to work out how much extra ease you need. You will also end up with excess ease in the sleeve cap.
In both of the cases above, if you would prefer the sleeve cap to have the minimal ease, you could reduce the Cap Height, and have a more Flared Sleeve rather than a Fitted Sleeve. This means (obviously) that your Fitted Sleeve won’t be very Fitted. But then…. How fitted does a fitted sleeve have to be, to be a fitted sleeve?
Examples
The two images below show where there may be insufficient ease to allow arm movement, even though there is sufficient ease for the bicep itself. You can also see the ramifications for the amount of ease in the sleeve cap.
Image 1:
- The brown sleeve has the correct Cap Height for a fitted look and a bicep measurement that is sufficient for the bicep itself, but there is insufficient ease for arm movement, as shown.
- The yellow sleeve has the correct bicep measurement to allow the full range of movement necessary. There is minimum ease in the sleeve head, which means there will not be any gathers. However, the low Cap Height (needed for to achieve minimum ease in the sleeve cap) means that the sleeve isn’t really the ideal fitted sleeve; it will flare away from the body.
- The dashed black line shows what will happen if the correct Cap Height and the correct Bicep measurement is used. You can see that the length of this line will be significantly more than either of the other two. This means there will be excess ease in the sleeve cap, which will result in gathers or tucks.
Image 2:
- The brown sleeve has the correct Cap Height for a fitted look and a bicep measurement that is sufficient for the bicep itself, but there is insufficient ease for arm movement, as shown.
- The yellow sleeve has the correct bicep measurement to allow the full range of movement necessary. There is minimum ease in the sleeve head, which means there will not be any gathers. However, the low Cap Height means that the sleeve isn’t really the ideal fitted sleeve; it will flare away from the body.
- The dashed black line shows what will happen if the correct Cap Height and the correct Bicep measurement is used. You can see that the length of this line will be significantly more than either of the other two. This means there will be excess ease in the sleeve cap, which will result in gathers or tucks.
Standard Bicep Sizes
This is a general guide to the size of the Bicep in relation to other body measurements. Measurements are in inches.Size | Upper Bust | Bicep |
---|---|---|
6 | 30.5 | 9.5 |
8 | 31.5 | 9.75 |
10 | 32.5 | 10 |
12 | 34 | 10.38 |
14 | 36 | 10.88 |
16 | 38 | 11.38 |
18 | 40 | 11.88 |
20 | 42 | 12.38 |
22 | 44 | 12.88 |
Sleeve Cap Distribution
This is information relating to Image 4 in the instructions – moving the bicep line to have the correct sleeve-head distribution. This is an example to show what we are trying to achieve with the steps relating to Figure 3 of the Sleeve Instructions.Image 3B
In this example, the front and back armhole measurements are significantly different: front = 9.38-inches, back = 10.31-inches.- The shape drawn in red shows the sleeve that is created using the symmetrical method.
- The shape drawn in black shows the sleeve that is created distributing the back and front armhole measurements separately.

Image 3C
The symmetrical sleeve has had the mid-shoulder line moved forward, and now not only the mid-shoulder points are lining up, but it can also be lined up at the bicep line. The symmetrical sleeve has a different shape to the sleeve created based on the actual distribution of the armhole measurements either side of the shoulder point.
Example Excess Ease
This is to show the difference in the final shape of the sleeve-head if your points G and J are significantly different.
This is my sleeve-head, and you can see that the pink line (Cap Height J, the body measurement) is significantly longer than the black line (Cap Height G, the ideal measurement that will result in minimal ease in the head of the sleeve).
The length of the sleeve cap for Cap Height G is 19.7 inches, and this include the ease required to sew the sleeve into the armhole.
The length of the sleeve cap for Cap Height J, there is an additional 0.89-inch (2.25-cm) ease. This will result in gathers or tucks, unless a dart is put in or a seamline (resulting in a two-piece sleeve).