Jeans Sizing, Problems and Recommendations

The second article from the technical journal I’m writing about is Jeans Sizing: Problems and Recommendations. Omitted from the title is that this refers to women’s jeans. The article was written by Professors Cassill and Delk. Straight away, the authors claim poorly fitting jeans are due to three reasons:

  1. The RTW market bases their sizes on the PS 42-70 data (aka, the much maligned Sheldon sizing study).
  2. Designers do not follow the PS 42-70 data.
  3. Women have hourglass figures and jeans are cut for a straighter body type.

Uh…one and two contradict each other and three isn’t necessarily true. Regarding the PS 42-70, I used to cringe when I heard educators (no offense intended, I’ve never heard anyone else say this) claiming that manufacturers used this data set to develop their sizing, now I just giggle. While I can’t know the practices of every manufacturer, I’ve never known one who did use this information. The sizing doesn’t work so it’s kind of silly for people to spread rumors saying we do when we don’t and haven’t in over 40 years (the sizing study is nearly 70 years old). If someone actually had been, they’ve either redeveloped their sizing or gone broke long ago.

The authors also disparage manufacturers and designers for developing patterns to fit their “average” customer. You already know I think that’s the best way to go. If everyone were forced to size their patterns to fit like everyone else’s, then half of us would be walking around with nothing to wear. I do not know why everyone presumes sizes would be designed to fit them. Who decides? All bodies are different. Why should a Neiman’s type brand be forced to size clothing the way a Wal-Mart brand does? I wrote a whole series on this topic (see the vanity sizing series) so I’ll spare you any further lecture, rather, the problem is a failure to convey the measures that constitute a given size to the consumer. It is not enough to indicate “size 10”. With jeans and pants, the size waist and hip that a given size 10 is intended to fit, should be included as well.

These issues dispensed with, the article is pretty good although I was also disappointed that the fit problems itemized in the chart (below) were not analysed for their root causes (poor pattern engineering). The professors selected a volunteer to test the fit of the jeans from 10 different manufacturers. Twenty-eight pairs of jeans were tested displaying these results:


The fit model was a little short for average (average is 5′ 4″) but was otherwise suitable. Her measures were:
waist 25″
hip 35″
inseam 28
waist to hip length 7.5″

In the article comparing the dimensions of the 28 pairs, the authors claimed that “jeans of higher price points tended to be larger per size than those of lower price points” but if you look at their chart carefully, there is only one instance of that. Other than the one sample, the lower cost jeans “outsized” the pricier ones. I don’t understand why they wrote that when their own data says otherwise.

The problems I see with the jeans (other than the aforementioned and linked to pattern engineering articles) is very poor grading and sizing practices. Also, the authors confuse the concept of one’s waist size being equivalent to actual fabric measure. If you have a 25″ waist, the fabric has to be greater than 25″ to allow for expansion, movement and normal wearing ease (say, to tuck a shirt in). Regarding specific details, Brand I, in the size 8, has a waist measure larger than the 10. The size 6 conversely, was too tight to even close. Brand J had identical waist measures in sizes 8 and 6. In numbered sizing, there should be an inch difference in the midrange of the size spread.

There is more material in the forum including the full size chart and supporting documents. I’ve decided to create gated content to encourage support of this site. I have to make a living and I can’t do that putting up free content forever.

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14 comments

  1. Darby says:

    There’s this company that’s conducting “anthropometic” (yikes!) research using 3D measurement technology… compiling all this data that manufacturers can use to improve their garment fit. Here’s the site: http://www.sizeusa.com/ Very interesting.

  2. Kathleen says:

    Darby, don’t feed the bears! :)
    The sizing usa study is one of my major pet peeves, I’ve written about it several times:

    There is one last study -for which I do not have data- known as the Sizing USA study because this falls under the auspices of TC2 rather than ASTM. [climbing up on soap box] It is undeniably the most accurate because the information is a compilation of body scans. This data set is prohibitively expensive -$20,000! The others I mentioned cost $28 or less. Personally, I am outraged over the cost. I am outraged because TC2 got a federal grant to do it, to say nothing of grants from businesses (who were then given tax breaks) yet we can’t afford to buy it. I think it’s outrageous that US tax payers paid for the study but we don’t have access to the data. How fair is that? Then insult to injury, TC2 runs around saying that manufacturers aren’t using the results of their study insinuating that we don’t care about making well fitting apparel. Well, most of the women’s apparel manufacturers out there are really tiny companies with fewer than 20 employees and knowing them as I do, I don’t see how they can pony up that kind of money to buy the information. This is pure politics and US consumers (and small manufacturers) are paying the price of hoarded information. [climbs down from soap box] You may safely surmise that TC2 doesn’t invite me to any cocktail parties. Come to think of it, a lot of people in this business don’t. I tend to say things that are very unpopular. And you thought I only rattled your cages.

    Also, here’s an excerpt from an entry called Size is a matter of opinion? that has some bearing on today’s entry:

    My first thought is that if you’re one of those people who think we should adopt mandated sizing for apparel, I’d think you’d be dissuaded of that opinion if you spend any time looking at these charts and data sets…My point being that I could see the apparel industry adopting standards if consumers and experts could agree what the standards were. As it is, the stats are all over the map. If we did adopt standards, there’d be a whole lot more people missing out in apparel choices than there are now. When women -between themselves- can agree what constitutes a size 10, then that’s the day the apparel industry will fall in line behind them. I feel safe saying that because it isn’t possible that women will agree that a size 10 constitutes X bust, waist, hip, height and weight measures. In other words, apparel sizing is all over the map because people are, in both physical dimensions and perspectives. It would seem that size is a matter of opinion.

  3. J C Sprowls says:

    Say… you think the bears will be at SPESA? I’m wondering if I can hire one of these booths to take my measurements so I can test out the results?

  4. anir says:

    The other part of the craziness of the data cost is that the people they scanned volunteered. They did not get paid or to my understanding any kind of compensation.

  5. Lisa B. says:

    Actually, if it’s the same people, and I think it was…Yes, people volunteered, but we got some money for it. I think it was $50 or less. They came to the Art Institute of Portland while I was attending. It still seems WAY outrageous that they’re charging so much!!!

  6. colleen says:

    In my experience, jeans sizing is tough because:

    manufacturing tolerances have to be generous to allow for the impact washing, dying etc has on the denim. Because of this, a size 6, for example, will sometimes have a larger waist (hip, inseam, etc) than an 8 (if the 6 is within tolerance on the plus side and 8 is within tolerance on the minus side)

    different denim colors require different production patterns (although must meet the same spec)

    the rise shape isn’t given enough attention in development or production; just hitting spec isn’t good enough if the shape is skewed (often the center back waist rides high on the body, but the curve of the back rise cuts into the body – not attractive or comfortable!)

    It’s also helpful in development to view a size run on “real people” and not rely solely on the fit model. Yes, it’s more work up front, but is worth it.

  7. Jennifer says:

    It is not enough to indicate “size 10”. With jeans and pants, the size waist and hip that a given size 10 is intended to fit, should be included as well.

    I second that motion!!!

    I label all the clothes in my store with as much info as I can get my hands on. Adhoc size e.g. 1x(12/14) as well as bust-waist-hip range, plus inseam & rise on pants/jeans.
    The one thing I like from EN 13402 is a European standard for labeling clothes sizes is section 2: Primary and secondary dimensions needed for garments.
    I wish all manufacturers included this info on their hangtags. This info makes it so much easier for the retailers and the customer to find the right product(s)

  8. jinjer markley says:

    Kathleen,
    I wonder if you might be able to get teh people at zafu to do a guest article on jeans sizing. They’ve tried enough jeans on enough body types to have an informed opinion (and their service is free–it’s essentially advertising for the jeans brands they recommend, so it works out for everyone)

    They’re also doing a fit study on bras right now, btw.

  9. Paula says:

    You seem like you really know your stuff and I have what is probably a “basic” fit question that I hope you can answer. My jeans always end up with a bunch of fabric in the back between the waist band and the top of my rear – doesn’t seem to matter what brand, style or how much I spend (or don’t spend), all of my jeans do this eventually. The end result is me hiking them up and securing with a belt that’s tighter than I’d like it to be. It seems to me that my back waist through the crotch measurement is maybe shorter than most but wouldn’t that be true in the front too? Any thoughts on what’s going on here and how to solve the problem? If I’m one of those people who needs to get my jeans tailored what would I even ask them to do so they get it? – I live in a small community where there aren’t many options for tailoring so that seems like a recipe for disaster. I do sew so maybe I can fix this myself? Any advice is appreciated!

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