Get the Perfect Fit: Grading the Bria Crossback Swimsuit

Written by: Jackie Pritchard



Time to read 4 min

girl in a blue cross back swimsuit

Grading between multiple sizes on a garment like the Bria Crossback Swimsuit and Leo can be a tricky process, especially given its unique design. But, correct grading is essential to ensuring the perfect fit. To make getting that perfect fit a little bit easier, we have put together a step-by-step guide to mastering the grading process for Bria!

Follow These 3 Steps Before You Grade

1. Take accurate measurements

When deciding if you need to grade, it's best to start with accurate measurements. Bria utilizes the following measurements for sizing. 

  • Chest: Place the measuring tape around the fullest part of the bust. 
  • Waist: Place the measuring tape around the natural waistline. This is normally around the navel. 
  • Hip: This refers to the full hip. Place the measuring tape around the fullest part of the booty.
  • Girth: Hold the measuring tape at the shoulder, measure down the chest, through the legs, over the fullest part of the booty and back up to the shoulder. 

drawing of girl with measurements marked

2. Use the finished measurement chart

In conjunction with the size chart, refer to the finished measurements chart when selecting your size. This swimsuit has 15-20% negative ease since a close fit is essential for swimwear. This means the finished measurements can be up to 15-20% smaller than your actual body measurements. 

If you are in between sizes, you can use the finished measurement chart to decide if you should size up, down, or cut between the pieces for a custom fit.  

Bria finished measurements chart

3. Understanding trunk girth 

Trunk girth is not a flat measurement like height or inseam. It is a measurement that factors in trunk length and body width measurements like bust, waist and hip – especially for adults. As the body measurements increase throughout the size range so does the girth because we need extra length to compensate for the increase in those width measurements.

For adults, the girth measurement is more reflective of body volume changes than trunk length changes since our adult heights are fixed. So when you only grade up in girth based on the measurements in the chart, you are often getting a lot more length than you actually need. Use the instructions in the tutorial to decide how to grade for girth. 

drawing of adult

TIP: Before printing or projecting your pattern pieces, make sure to use the layer function to turn off any unnecessary layers. This really helps to streamline the grading process, ensuring focus on the relevant sizes and minimizing confusion!

Grading the Bria Pattern Pieces

Grading diagram for the Bria swimsuit

The diagram above will be helpful in determining which parts of the pattern piece you need to adjust based on which measurements. Make note of how you need to grade each piece based on the measurements and the chart above. 

bria grading diagram

Start by marking all the major height and width points on your pattern piece. These are the horizontal and vertical lines shown in red. These lines will serve as guidelines for precise grading, ensuring consistency and accuracy throughout the process.

bria grading diagram

Redraw each pattern piece, making sure that major points for width and height align with your marked lines. Pay close attention to maintaining smooth curves and following the original lines as closely as possible. This step is crucial for preserving the integrity of the design while accommodating size variations. Note: the new pattern pieces in the diagram above are drawn in blue.

Bria grading diagram

For those choosing the colorblock version, you may need to use the lining piece to true up the side cut out section of the pattern piece. Overlap the main and lining pieces and follow the curves of the lining to make sure that your grading is accurate. 

Troubleshooting & Making Personal Adjustments

Excess fabric on the back bottom piece

If you have some excess fabric on the bottom back piece or you feel the bottom back piece is too tall there are a couple easy adjustments to fix this.

  1. You can remove some height from the center of the bottom back piece then redraw the top of the piece as shown in red of the photo. 
  2. You can also remove some width if needed from the top of the sides and redraw the sides of the piece shown in red of the photo.

Note: With these adjustments, the elastic may need to be adjusted slightly. You can easily add or remove length to the elastic as needed based off your personal preference and fit.

drawing of girl with measurements marked

Armscye feels too tight or too small

If the armscye feels a little too small or too tight you can easily lower the armscye on your piece based off personal preference. You will just lower the bottom point and redraw as shown in the photo. 

When you adjust the armscye you will adjust need to add the same amount to the sleeve or the elastic. The elastic is attached at a 1:1 ratio so you can measure the new opening and cut the elastic to the new length.

Bria armscye adjustment

Elastic Adjustments

When you grade between sizes, the elastic measurements may not be accurate for your new pieces so it will be best to add or remove length based off personal preference. 

Note: The elastic on the legs and armhole are attached at a 1:1 ratio and the back elastic is calculated at 87%.

That's it! You did it!

photo of a woman in a black shirt

Jackie Pritchard

Thank you for reading along and I hope you have gained some valuable insights on how to grade the new Bria Crossback Swimsuit & Leo pattern. 

Happy sewing, friends!

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