While many of us yearn for, and diligently work towards, mass customization the reality of the time is that pattern shaping has been traded for garment stretch. Garment fit is an industry wide complaint with numerous complexities inhibiting a solution. To compensate, manufacturers use garments made from stretch fabrics to camouflage fitting concerns. This can be a very effective solution as long as a pattern’s ability to stretch is not exceeded. A waistline that can stretch to accommodate size fluctuations of three to four sizes difference definitely accommodates a larger target group but just because a garment can stretch does not mean it should.
Overall, the use of stretch fabrics to offer a pseudo customized fit has merit. Problems arise however when a stretch pattern, is reused to create other designs, and then those designs are yet again reused to create even more designs. Eventually fit integrity is compromised, if not lost. Necklines, shoulders and armholes will be too wide or narrow. Waistline locations will migrate up or down. Even common girth measurements can be misconstrued. Pattern modifications can correct these distortions but to truly isolate the fit issue it is often best to critique the stretch pattern against the “woven” base from which it originated.
Stretch patterns are essentially strategically scaled down versions of a woven pattern. The degree to which a pattern for a stretch garment is scaled depends on the percentage of stretch of the fabric and the tension under which the garment will be placed. The difference in stretch patterns may only be noticeable at the side seam or hem but a correctly designed stretch pattern will have been strategic reduced in length and girth at several key locations as per the requirements of the fabric. The following image illustrates a woven pattern reduced for different stretch fabrics. The horizontal and vertical lines through the patterns reflect how the pattern is proportionately resized for stretch fabric.
Different stretch fabrics require different pattern measurements. Identical designs produced in two different fabrics, one with 20% stretch fabric and the other with 40% stretch fabric, with l require a different patterns. (This may be common knowledge to many but, as I have recently discovered, it is not to all.). The following chart illustrates how very basic girth measurements are adjusted for various stretch fabrics. The chart illustrates only three of over 150 measurements that truly need to be analyzed yet reinforces the fact that the same stretch pattern cannot be used for all stretch fabrics.
Adjusting a pattern for stretch fabric involves more than just hem and side seam modification. Sadly, the importance of pattern making is often downplayed in the race to the retail rack. The fact remains, no amount of fabrication or detailing will mask a garment derived from a poorly fitting pattern while poor fabrication and detailing are often overlooked in a well fitting garment.
Until industry wide fit issues can be addressed I believe that stretch fabrics are an excellent fit improvement tool for manufacturers but fit integrity is an issue to watch. Stretch patterns must periodically be critiqued against a woven block pattern equivalent. By returning to the original woven base pattern equivalent (block), length and girth stretch adjustments can be analyzed and fit errors can correctly be traced. In a virtual environment this procedure can be automated and future CAD MTM programs will have this incorporated. Until then, manufacturers should have detailed negative ease measurement charts for working with stretch fabrics. A chart such as the one illustrated below allows those involved in production a necessary assessment tool for monitoring pattern length and girth integrity.