One of the biggest questions when we embark on a sewing project – to wash or not to wash? Most people say you should. That’s the proper way to do it. But sometimes you just can’t wait to get started, and sending it off to get washed will disrupt your sew-jo. I get that 😛
My rules are – if it is meant to be worn, and the garment is fitted, or has a lining of a different material, please pre-wash according to the instructions. Don’t waste your effort – tracing, cutting carefully, taking care with every stitch, only to find that after washing it no longer fits because you skipped this important step.
When do I not prewash? If the garment is a loose fitting one, or when making bags where shrinkage is not terribly important.
Having said that, not all fabrics come with washing instructions. Sometimes it takes a combination of experience (meaning a fair amount of ruined projects due to unforseen shrinkage) or just take a guess from the fabric composition.
There are a few new substrates available in this year’s nani IRO 2019 collection, so I thought I would do a quick shrink test to help you take the guesswork out of the process! I cut 10cm x 10cm squares, put them all in a laundry bag since I did not want to serge the edges as that might skew the results).
The fabric was then washed at a 30C, regular cycle, followed by a dryer on normal mode, then ironed at medium setting. Much like how I wash my regular wear. I have been washing all my nani IRO double gauze and thin linen tops this way for the longest time and they are still in great shape.
Here are the before and after pictures for your comparison. Please ignore all the fraying bits. Lost some threads (especially the weft threads) as the fabric wasn’t serged.
I can’t say to be for sure if this is the first time single gauze is appearing on the range of nani IRO fabric, but there seems to be quite a number of fabrics in this substrate. Single gauze is basically, just one layer of gauze. When I think about single gauze, I think bandages, and also the very thin, wrinkly fabric sold in Spotlight for making baby nappies or wraps. However, the nani IRO single gauze is really smooth, especially those from the temps range. It is not wrinkly at all, and the only problem is that is very sheer and needs to be lined.
Taking the selvedge edge of the fabric (the black line on the right) as a reference point, and comparing the printed text, the fabric shrank about 2-3mm both vertically and horizontally. So the shrinkage both width and length wise is about 2-3%.
The mainstay of nani IRO fabric is double gauze. Light and cooling yet not sheer to require lining. This is literally my go-to fabric for daily wear and the prints of nani IRO makes me feel happy all day long! 🙂 Great for spring and summer wear and also for layering. In cold weather this is also great as a neck warmer or infinity scarf. Very cozy and versatile fabric.
In the picture I used the words on the side of the selvedge to compare the before and after lengths. The shrinkage for double gauze is about 3mm lengthwise and 2mm widthwise. So that’s a shrinkage of 2-3% as well. Double gauze should be prewashed before sewing. But I usually don’t. That’s because most of the patterns double gauze are suited for, tend to be easy fitting.
Rexcell (レクセル) is a cellulose derived fabric. Quite similar to rayon in hand feel, it is soft and has a beautiful luster. This fabric is developed by a Japanese textile company Fujibo Textiles and is touted to be highly absorbent, soft, drapey and made with ecological methods without use of harsh chemicals. (according to the company’s brochure).
click on image to see larger version
This was a little harder to compare as there were no clear markings. Some of the weft threads came apart during the wash so it does fray a little though not as much as gauze. There seems to be a very slight shrinkage along the grainline (length parallel to selvedge) but it’s about 1-2mm so that’s a 1-2% shrinkage. If you are using it for a fitted pattern, then I would suggest you prewash it!
click on image to see larger version
Comparing the markings on the before and after pieces, there seems no clear shrinkage. The fabric after looks slightly warped but that’s probably because of my ironing. Some fraying as expected with linen but other than not much shrinkage, maybe only by 1mm?
Do bear in mind that the results of the shrinkage test when extrapolated will be more significant. Say a 100cm long dress, with a 3% shrinkage the hem will move upwards by 3cm. So I would say, always prewash your fabrics if the pattern is fitted or the length is critical. You don’t want to spend hours sewing and end up with something too short or too tight to wear.
Personally, I skip prewashing because firstly I’m lazy, and secondly I tend to gravitate to patterns with lots of ease. It is also because patterns that are more suitable for linens and gauzes tend to be more loose fitting. I have tried making a fitted pattern with double gauze before and due to the lack of structure it didn’t look fantastic. But that’s me 😛 From my personally experience of double gauze and thin linens, I wear them all the time, wash and dryer cycle with all my regular laundry and no issues at all!
Disclaimer : I know my methods are hardly scientific, but I tried my best to do a proper comparison. If you have any doubts, just pre-wash everything! 😆