As most patterns are cut to fit a B cup, you may need to make a full bust adjustment if you are bigger or smaller than a B.
Whilst it can seem a little daunting to anyone new to pattern adjustments, this really can make a massive difference to how your clothes fit.
If you have a small frame, with a full bust, and you use your bust measurement to select a pattern size, the chances are that the clothes won’t fit around your neck, chest and armhole.
If you’re smaller busted, you may have unsightly excess fabric folding around the bust.
If your full bust measurement is bigger than your high bust by more than 2.5” (6.5cm) you’ll need to do a full bust adjustment (FBA). In this case, use your high bust measurement as your base pattern size.
If your full bust measurement is 1”(2.5cm) or less than your high bust, then you’ll need to do a small bust adjustment (SBA). Use your full bust measurement as your pattern size in this case
There’s no exact science to measure how much of a bust adjustment you’ll need. It also depends on whether you’re making a loose-fitting garment.
First of all you need to work out how much additional space you require around the bust or what you’d like to remove. Below is a helpful chart to work out the amount.
The process of adapting the pattern for both types of adjustments are the same except that for an FBA, you will spread the pattern to add space and for an SBA you will reduce space by overlapping the pattern.
Draw in the lines as per an FBA adjustment. Cut the lines as previously instructed. Now we essentially perform the same process in reverse.
Swing the darted side of the pattern across the other side, by the desired SBA amount. Your waist and bust darts will both be reduced. The lower edge of the hem no longer meets at the bottom, as the side that has been adjusted is now shorter.
Cut the third line you drew, and overlap until your hem is level. Re-blend the lines around your adjusted bust dart.
Compare the front and back bodice pieces along the underarm seam – folding the bust dart out of the way – to ensure your bodice will be the same length the whole way around!