Joan shirt sew-along – 2 Pattern adjustments

Customizing your Joan pattern

Welcome to part 2 of the Joan shirt sew-along!

In this post, we’ll compare our measurements to the pattern’s, and decide if we want to make any changes, and how. 

You will get an overview of some of the most common pattern adjustments, and a tutorial of the rounded back adjustment that is less common.

Pattern adjustments can seem scary, knowing where to start and in what order to make them. But it doesn’t have to be complicated. Follow along, take your time and you’ll soon learn the adjustments you’ll use the most by heart.

Before going ahead with the pattern adjustments, make sure you’ve:

  • decided what design features you’ll include in your  shirt 
  • gathered all supplies you need to finish the it
  • taken your measurement and have them at hand

When you’ve got that in place, let’s get started.

Table of Contents

Decide what adjustments you’ll make

In this sew-along I’ll be sewing the Joan shirt for a friend of mine (because I already made myself three 🙂

I’ve already printed the nested sizes I need, and graded between them to match the measurements on my list. 

If you haven’t printed your pattern and want some tips and tricks, you can learn more about printing and grading between sizes in this post

There are different ways to approach pattern adjustments and sometimes you use different ways depending on the garment type. When you’ve made pattern adjustments a few times you’ll find what works best for you.

I prefer checking and adjusting the measurements from the middle of the body to the sides and from the top to bottom. 

I start by re-checking the measurements after I’ve graded between sizes and cut out the pattern pieces.

Re-checking bust, waist, and hip


My model’s bust measurement is 2 cm / ¾ in larger than the shirt bust measurement and her back width is 2 cm narrower, so the total circumference matches the pattern.

Since the Joan shirt has a good amount of moving ease around the bust and back I won’t do a bust adjustment. The wearing ease and the back pleat will equalize the difference between the front and the back.

Tips! If this was a fitted shirt I wouldn’t skip this alteration. You’d want the side seams to fall in the middle, between the front and the back of the body. 


The grading between sizes I did in the previous post took care of the difference in circumference between my model and the pattern measurements, so no need for additional adjustments.


I also adjusted the hip measurement when grading between sizes, so this one is ready too.

Grading between sizes
Grading between sizes

Shoulder width

Checking my friend’s measurement list, I decided to extend the shoulder width by 0.5 cm / ¼ in.

I double-checked the notches and marks and placed a new mark on the shoulder seam. To know where to add it, I measured where the old mark was located and matched that measurement to my new shoulder seam line.

Reposition marks
Reposition marks

Tips! When you’re changing the shoulder width, the armhole or the sleeve cap, it’s important to keep the amount of ease as before the adjustment.

The easiest way is to calculate the cap ease, i.e. the difference between the armhole and the sleeve cap measurements, on the pattern pieces before you start adjusting. 

Shirt length

My friend is about 7 cm / 3 in taller than the Morphí fit model. Her torso and arms are 2.5 cm / 1 in longer and her back length measures 5 cm / 2 in longer than the shirt back and she has a slightly rounded upper back. 

Comparing her front and back measurements to the shirt finished measurements, there is an uneven difference. I’ll solve this by lengthening the front pattern piece by making an uneven length adjustment.

Uneven length adjustment to the front and back

I’ll add 2.5 cm / 1 in to the front and 5 cm / 2 in to the back.

To keep the side seams the same length I’m dividing the 5 cm that I’ll add to the back between the bodice and the yoke. 

First, I’ll lengthen the front and back bodice by cutting the pattern pieces at the lengthen/shorten line and then adding a 2.5 cm / 1 in wide paper strip. 

Lengthening the back
Lengthening the back

Lengthening the sleeve and facing

The sleeves and facing are lengthened the same way as the bodice i.e. by cutting the lengthen/shorten line by adding and taping a 2.5 cm / 1 in wide paper strip.


Lengthened sleeve
Lengthened sleeve

Rounded back adjustment (tutorial)

The remaining 2.5 cm/ 1 in I’ll add to the yoke as a rounded back adjustment.

  1. Trace the yoke onto another piece of paper
Trace off the yoke
Trace off the yoke

2. Cut out the new half,  then tape the two pieces together. 

Tape the pieces together
Tape the pieces together

3. Mark the seam line, 1 cm / ⅜ in from the cut line.

4. Draw a line between the two armholes, then cut to but not through, the seam lines. Open up the cut line and separate the halves as much as needed, in my case 2.5 cm / 1 in. 

Cut to not through the seam line
Cut to not through the seam line

5. Fill out the gap with paper, or re-trace the pattern piece on a new paper. True the armholes so the seam and cut lines are smooth. 

Tips! In this stage, I cut the new yoke in half on the center back line. I do that to make sure the cutting lines will be identical on both sides of the yoke when it’s time to cut the fabric.

Re-trace the new pattern piece
Re-trace the new pattern piece

6. Lastly, check all of your pattern pieces and adjust notches, marks, darts and, seam lines so they’re in the correct place and lining up without gaps.

Here’s what my finished pattern pieces look like:

Finished pattern pieces
Finished pattern pieces

Your next step

Good job getting to this point!

There’s just one more step before it’s time to start sewing. Finally!

In the next post, we discuss different ways to prepare the fabric to ensure it’ll be safe and easy to sew and wear.

Head on over to Part 3 – Fabric preparations.

Sew great

signature flaming needle

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