Full Bust Adjustment

Sew Me Something April 18 2015-155- Web Quality8.jpg

Getting a garment to fit you just right is one of the reasons we make our own clothes. And one of the areas of fitting I get asked about the most is the bust.

Usually we look at the bust measurement to determine the size we should make. However, most commercial patterns are cut to a B or sometimes a C cup. Which if you are a B cup is great. But a lot of us aren’t, so this can mean that you end up cutting a larger size than you actually need, leading to wider shoulders and gaping necklines.

This tutorial will show you how to add the extra fabric you need through the bust area without altering the armhole or side seams.

It can be difficult to work out exactly how much extra you need, but there are two main methods.

Method One

One way is to make up a toile or ‘muslin and slash a cross through the bust point. Insert an extra piece of fabric underneath the slash and however much the slash opens will show you how much additional fabric is needed through the bust, just measure the extra fabric.

Kate Dress Tutorial-44.jpg

Method Two

The second method is to measure your high bust, (just under your armpits across the chest but above the bust line).

Kate Dress Tutorial-2.jpg

Then measure the full bust and work out the difference.

Kate Dress Tutorial-4.jpg

For example, if your high bust is 99cm and your full bust is 105cm the difference is 6cm. As we work on half the pattern, we need half this measurement, so the amount needed for the adjustment will be 3cm.

Now you have worked out what the adjustment should be, we can add this to our pattern. I am going to show you the Full Bust Adjustment on the Kate Dress pattern.

Full Bust Adjustment

First draw in the bust dart.

Kate Dress Tutorial-7.jpg

Now draw a line through the centre of the bust dart and extend it out by 3 -4cm to the bust point. This is Line A.


Draw a line from the bust point down to the hem. Make the line parallel to the centre front. This is Line B.


Mark in the seam allowance around the armhole, in this case it’s 1.5cm

Kate Dress Tutorial-10.jpg

Draw a third line from the centre of the armhole sewing line to the bust point. (The point on the armhole doesn’t have to be where the notches are). This is Line C.

Kate Dress Tutorial-13.jpg

Kate Dress Tutorial-15.jpg

Cut up from the hem along Line B though to the bust point.


Kate Dress Tutorial-19.jpg

Continue cutting from the Bust Point to the armhole, but DO NOT cut through the seam allowance.


Now turn the pattern around and cut through the seam allowance on the armhole to create a paper hinge.


Cut through Line A up to the bust point but still leaving it joined with another paper hinge.

Kate Dress Tutorial-23.jpg

Kate Dress Tutorial-25.jpg

Draw a final line across the front section,half way between the bust and the waist, and at right angles to the centre front.


Cut straight though this line.


Your pattern is now slashed open and ready to be moved apart to add in the extra fabric that’s needed.


Transfer your pattern onto a large piece of paper and carefully tape down the front section. Masking tape is brilliant here as it can be lifted and moved if it’s not in quite the right place.

Line up the pattern pieces so the cuts are all closed. Carefully pull down and out the bottom left corner of the pattern.


Measure out from the bust point however much you need to add through the bust, and mark a point. Now I’ve done this on my dark green cutting mat so it’s easier to see, but you’ll need to draw a line from this point parallel to the centre front down to the hem. Place the side piece on this line so the gap between the front pieces is the same all the way down.


This will cause the dart to open out dropping down the bust point…

Kate Dress Tutorial-41.jpg

…and the seam allowance on the armhole to overlap slightly.


Carefully tape down the pattern pieces. So although we have added extra fabric through the dress we haven’t altered the armhole stitching line or the length of the side seam, although we have made the dart larger.

We are nearly there, but you may notice that the hem lines don’t match.


That’s easily sorted. Drop down the bottom section of the front piece so the hems line up.



Now to tidy it all up.

We need to mark back in the bust dart so draw a line through the centre of the widened bust dart. Mark a point 4cm in from the new bust point. The new bust point can be taken from the side section of the front. Draw in the legs of the new dart from this point.

Fold out the dart as if it had been sewn and cut away the excess paper down the side seam. This will create the correct shape to make sure the dart sits properly on the side seam.

And there you have it the Full Bust Adjustment to allow for extra fabric through the bust but still retaining the fit of the original pattern at the shoulders.