'Project Runway' Star Tim Gunn Calls for Fashion Industry to 'Wake Up,' Prepared for Backlash

— -- Tim Gunn is taking on the fashion industry, saying it’s time to design for women of all shapes and sizes.

Gunn, one of the biggest names in fashion, wrote in a Washington Post essay that designers “refuse to make clothes to fit American women,” calling it not just a poor business decision, but also “a disgrace.”

“Actually I’ve been saying this for a very long time,” Gunn, 63, said today on “Good Morning America”. “Christian Siriano and his work for Leslie Jones for the premiere of ‘Ghost Busters’ was really the catalyst for this Washington Post article. I’ve been an advocate for women who are larger than a size 12 for many, many, many years. And there are 100 million of them, so why doesn’t this industry wake up?”

With new research from Washington State University showing that the average American woman wears between a size 16 and 18, Gunn says there is money to be made in plus-sized clothing, but some designers and merchandisers believe “the plus-size woman is complicated, different and difficult.”

In the essay, Gunn urges designers to reconsider this bias, saying, “There’s an art” to creating beautiful clothes for larger women that skim the body rather than hug and cascade.

“What really baffles me is why retailers aren’t vigorously on top of this issue because all they can do is make more money,” he said on “GMA.”

Gunn hopes that as “we become a more inclusive society and culture here in this nation,” that we also become “much more open to different points of view, different individuals who possess different characteristics, [and] that the woman who is larger than a size 12 will become a part of that entire equation and that designers and retailers will respond to that individual.”

He thinks designers' way of thinking is old-school and out-of-date.

“I believe it just goes back many, many decades to the origins of our fashion industry and this rarefied, glamorous world that the industry wants to portray, and they say that the larger woman isn’t part of this,” he explained. “And everyone needs to be included and I think there’s nothing greater and more wonderful than saying, ‘Look, I can take someone who isn’t a 7-foot-tall glamazon and make that individual look fabulous.’”

The “Project Runway” mentor even criticizes his own show, saying it “has not been a leader on this issue,” claiming the contestants “audibly groan” when asked to create looks for non-models.

“Yes, I was very trepidatious about the article,” Gunn said of his reservations to address the issue. “I had a lot of tense moments thinking ‘Is this really the right thing to do?’ Well no, that’s not correct. It is the right thing to do. But will it create some potential backlash? I was willing to take that on.”

ABC News reached out to “Project Runway” for a comment but they declined.

The new season of "Project Runway" premieres this Thursday on Lifetime.