Fabric shrinks when it is washed. This is one of the common facts of fabric quality. How much fabric will shrink is not predictable. As fabric shrinkage varies from one type of fabric to another. Even roll to roll shrinkage variation is found for the same fabric and in the same order (due to lot variation). Woven fabric shrinkage (2-4%) will vary from knits shrinkage (3-8%). Shrinkage of stretchable fabric (10-18%) is higher compared to normal woven fabrics.
In this article, I will share common practices followed by garment manufacturers to control fabric shrinkage in the fabric as well as in a garment. To control fabric shrinkage to wash you first need to test fabrics prior to taking any action. Common processes of measuring fabric shrinkage are discussed here.
1. Measure Fabric Shrinkage and add shrinkage to the pattern:
2. Make a garment sample and measure shrinkage:
In this article, I will share common practices followed by garment manufacturers to control fabric shrinkage in the fabric as well as in a garment. To control fabric shrinkage to wash you first need to test fabrics prior to taking any action. Common processes of measuring fabric shrinkage are discussed here.
1. Measure Fabric Shrinkage and add shrinkage to the pattern:
Garment manufacturers cut fabric swatch from all fabric lots received from fabric suppliers and send to a testing lab for measuring (testing) fabric shrinkage percentage. This test can be performed by fabric store itself. There are two processes to find fabric shrinkage in fabrics. Learn more about measuring fabric shrinkage
- In fabric swatch: 100 X 100 cm fabric swatch is cut and marked length and width wise. Fabric is washed and post wast length and width variation is checked to find fabric shrinkage percentage.
- In blanket form: Instead of fabric sample, a blanket is made with the fabric (3 sides closed and one side open). The blanket is washed in the washing machine and shrinkage percentages are recorded.
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2. Make a garment sample and measure shrinkage:
Fabric shrinkage percentage can be measured in the testing of fabric swatch but you will get different shrinkage percentage when tested in garment form. So, garment manufacturers make 2-3 samples on the base size on receiving bulk fabric lot. Samples are processed as per the bulk process (washing, drying). Shrinkage percentage is measured and recorded. The shrinkage percentage on lengthwise and widthwise is incorporated into production patterns.
To ensure that shrinkage is added to the production patterns, garment manufacturer makes sample-based on modified patterns and same processes followed if they get correct measurement after washing those sample. Factory may need to develop multiple patterns for the same style based on variation ins shrinkage% in fabric lots.
3. Relaxing Fabric prior to cutting:
To ensure that shrinkage is added to the production patterns, garment manufacturer makes sample-based on modified patterns and same processes followed if they get correct measurement after washing those sample. Factory may need to develop multiple patterns for the same style based on variation ins shrinkage% in fabric lots.
3. Relaxing Fabric prior to cutting:
Garment manufacturers open the fabric roll and relax fabric overnight (e.g. for 12 hours). Fabrics are also relaxed for another 12 hours after layering on the cutting table. After the relaxation process fabric is cut for production. This process is done even shrinkage is added to the pattern.
4. Cut Panel Laundry (CPL):
4. Cut Panel Laundry (CPL):
In knits, the fabric shrinks and get twisted after washing. To preshrink the fabric and to improve the dimensional stability of the knits fabric, the fabric is cut into a certain length and washed. This process is known as cut panel laundry. In CPL process fabric is completely preshrink and no need to change the base pattern prior to bulk cutting. Relaxation is nor needed for CPL fabrics.
Why to measure fabric shrinkage?
If you are a beginner, you might like to know why one should measure fabric shrinkage. Here are the reasons:
You could not expect that you will get fabric with zero shrinkage. So you have to take care of the fabric shrinkage through production processes to make garments of right fit. Whether you pack washed garments or garments without a wash, you need to match garment measurements with specs. There is a risk of having spec variation (out of measurement tolerance) in both cases if shrinkage is not taken care off. Shipment might be rejected buyer if measurement variation is found in the final inspection.
Secondly, fabric consumption (in grams) per garment will increase if the shrinkage percentage increases. To source correct fabric volume (Kilograms, meters), you need o known average shrinkage percentages of the fabric in advance.
Above methods are followed by most of garment manufacturers to minimize measurement variation in garments occurred due to fabric shrinkage. If you practice other method(s) to control fabric shrinkage, we like to know it.
Secondly, fabric consumption (in grams) per garment will increase if the shrinkage percentage increases. To source correct fabric volume (Kilograms, meters), you need o known average shrinkage percentages of the fabric in advance.
Above methods are followed by most of garment manufacturers to minimize measurement variation in garments occurred due to fabric shrinkage. If you practice other method(s) to control fabric shrinkage, we like to know it.