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This Company Is Making Footwear Out of Wool, Sugar and Trees


Your average wool material has a dense, scratchy feel and is great for trapping heat - probably not something you would want wrapped around your feet on a summer day.

With that in mind, how is it possible to make a wool shoe that is both comfortable and fashionable? The answer starts with using the right kind of wool, originating from merino sheep. This realization led Tim Brown, an ex-soccer player, and Joey Zwillinger, a former executive from a renewable energy company, to conceive Allbirds and the company’s flagship shoe, the Wool Runners.

Founded in New Zealand and currently operating out of San Francisco, Allbirds offers three different styles of footwear: sneakers, loungers and flip-flops (as in the photo above). What makes them so special is that each shoe is derived from ethically- and sustainably-sourced merino wool, tree fiber or sugar -- a major development in an industry that is looking to reduce its high carbon footprint as a result of the manufacturing process.

Full disclosure: if you are looking for a fluorescent, “high-tech” fashion shoe that is graced with a large company logo, then Allbirds may not be for you.

The origin story of the company goes that Brown, a native of New Zealand, where humans are outnumbered by sheep 6-to-1, was puzzled as to why a sustainable resource like wool was not being utilized in the footwear industry. Brown’s curiosity led to the creation of the trendy Wool Runners. A line of sneakers and loungers made from sustainably-grown tree fibers was added to the product line earlier this year.

“We found a way to turn one of the world’s most amazing renewable resources (wool) into a wickable, breathable, comfort experience that’s like being upgraded to first class,” said Brown in a 2016 company video introducing the Wool Runners. “We dispensed with flashy logos, unnecessary detailing and a focus on synthetics to create something we think the footwear industry has been crying out for -- something better.”

Allbirds shoes are about simplicity, comfort and sustainability, the company explains on its website. By dropping the flashiness seen across most major shoe brands, plenty of room is left to focus on incorporating renewable materials across the product line -- from the wool uppers, to laces made from post-consumer polyester, to the packaging used for shipping. The results are a small but meaningful lineup of some of the most popular styles of shoe that goes beyond conventional production for the sake of the environment.

Now, the startup’s latest venture appears to be taking on the very sole (pun intended) of today’s kicks.

On August 1, Allbirds introduced their limited-edition Sugar Zeffers. The shoes look like your standard pair of flip-flops, but what makes them so unique are their bottoms.

Allbirds has developed an outsole, appropriately called SweetFoam, made from green ethylene vinyl acetate (EVA) that uses sugarcane as the primary substitute for petrochemicals commonly found in most foams. Grown in southern Brazil where the rainfall is plentiful, the sugarcane’s biomass is also used to power the processing mills and fertilize the next year’s crop; Allbirds has dubbed its foam “the world’s first carbon negative green EVA.”

While the idea of “sugar shoes” may sound quirky, the big news here is that the company was able to develop an EVA foam devoid of petrochemicals like oil. In its effort to make footwear a greener commodity, Allbirds has also put its money where its mouth is by making the EVA formula openly available to any shoe manufacturers that are interested.

Widespread adoption of the green outsole could be just what is needed to reduce the environmental cost of a pair of shoes, which a 2013 study conducted by MIT found generates carbon dioxide emissions equivalent to running a 100-watt light bulb for one week.

Image credit: Allbirds