To Pre-shrink or Not

Some think that it's unnecessary to pre-treat fabric. 

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Yet anyone who has purchased ready-to-wear (RTW) and has lost a garment in just one wash due to shrinkage knows that manufacturers often cut out this step in order to get garments to the market quickly. Maybe that is why the RTW landscape is over run with oversized basic baggy styles? As sewists, we're in control of the quality of the items we sew. So, the question today is do you preshrink your fabric before cutting out a project?   

Cotton stretch shirting fabric.

Pressing out the length of cotton shirting fabric that I plan to use for the next project, I noticed a that my fabric shrunk both in the lengthwise and crosswise grain by a noticeable amount. Luckily, there was enough fabric to cut out all of the pattern pieces. I always pre-treat my fabrics before I cut them out but to be completely honest, my motivation is more about having a cleaned product on my cutting table. The length of fabric came from a shop that had a cat.  I'm terribly allergic to cats. But I digress...

Back to the question of pre-shrinking your fabric. Vogue Sewing, my go-to sewing reference book instructs us to shrink fabric if it hasn't been pre-shrunk by the manufacturer or if it will shrink more than 1% according to the label.  

The advice written in this edition of Vogue Sewing was written in the mid-nineteen-seventies.  I don't know about your local fabric labels but this is unheard of in this part of the world. As a matter of fact, I've never seen a fabric label that contains this information. It's more common to find "unknown fibres" stamped across fabric labels found at the local Fabricland and even more rare to find a label at Northwest Fabrics.   

Vogue Sewing doesn't go into how to test if a fabric is prone to more than 1%, for this information, I was able to discover the method in Sew A Fine Seam, circa 1955. 

If possible, procure a generous sample--at least 1 x 2 inches in size, with a selvedge--so you can easily determine the lengthwise and crosswise grain of the fabric.  Trim the raw edges of sample so the edges are "clean cut."  Cut a piece of paper the exact size of the sample.  Wet sample thoroughly and lay flat to dry.  Do not press dry.  When sample is completely dry, compare with paper.  The slightest difference in size indicates shrinkage. Supposing your fabric was cotton, 36 inches wide and the shrinkage was 1/32 of an inch in the lengthwise grain and 1/16 of an inch in the crosswise grain.  This may seem a very slight amount, but in a yard of fabric, it is enough to result in a snug garment after it has been laundered or dry cleaned (Wilson, 35-6).

This method is basically explain in here as well.

I didn't do the sample test on the piece of fabric I was pressing when I noticed that the crosswise grain was smaller than prior to the tumble in the washing machine followed by the dryer cycle. Instead, I measured my the lengthwise grain before and after and discovered that I lost 0.3 metres in the process.  I'm quite relieved that it shrunk before instead of after I sewed my project. 

Allowance for Shrinkage

What do you do if you're trying to decide on how much fabric is needed for a project when you're not in the position to do the shrinkage test?  Pattern companies don't incorporate a shrinkage allowance when listing the yardage requirements.  It would be a tough thing to suggest considering that different fabrics behave differently when washed or dry-cleaned.  

Sew A Fine Seam provides a quick general guideline:  

• Allow 1/8 yard or 0.11 metres for a blouse, skirt, or jacket.  
• Allow 1/4 yard or 0.23 metres for a dress, suit, pajamas, or coat
• Allow 1/3 to 1/2 yard or 0.30 to 0.46 metres for a floor length garment if the width of your fabric is 36" or 54" respectively.  

If I went with this I would have underestimated how much shrinkage would have occurred with the cotton stretch fabric on my cutting table. These recommendations are from last century when body shapes, clothing styles and fabrics were different than they are today so I would only take them as a interesting footnote rather than a steadfast rule.

I do like the sample test for shrinkage as a reference but to be honest, I don't really put that much research into how much a fabric may or may not shrink.  How about you?  Or do you just cut and hope for the best?

Happy Sewing!