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The Merino Air Hoody: A Most-in-One Base Layer


The author guiding on Mt. Arkansas (13,795), Colo.

[Photo] Bill Warner

Because I guide year-round on all types of terrain, from rock to ice to alpine, my closet is filled with outdoor clothing of all types. The base layer section of my closet–yes, it has its own section–contains synthetics and wool in short sleeve to long sleeve in light, mid- and heavy-weight varieties.

Recently I added Patagonia’s Merino Air Hoody base layer to my collection. Unlike my other merino wool items, The Air Hoody, with its fluffy appearance, resembles a thin, non-itchy sweater more than a typical next-to-skin layer.

Size medium weighs 7.3 ounces. This is less weight than both the Rab MeCo 165 Hooded Top, at 10 ounces, and the The Melanzana Wind Pro 200 Hoodie, at 18.9 ounces.

I wore the layer over 30 straight days this spring. During this time, I instructed a multi-day avalanche course, guided rock, ice, alpine, and ski mountaineering and kept it on during rest days in Estes Park. Sometimes I even wore it out for a night on the town because it also works as a casual layer.

Though I washed it several times during this period, I took care to not throw it in the dryer. (I take this care with all my wool layers so they last.)

The author guiding climbers on the First Flatiron in Boulder, Colo. The hood of the Merino Air Hoody can be seen under the author’s helmet.

[Photo] Jon Feder

The Merino Air Hoody is made with 51% merino “lofted” wool, (wool that’s been poofed out with air), and 49% recycled polyester called Capilene. It’s constructed using “an innovative air-jet process that creates yarn of greater loft and insulation value than conventionally spun wool,” states Patagonia. It is also seamless to reduce hotspots. The Hoody has a snug, athletic fit and is stretchy and works as both a base layer and as a second layer. For example, I wore it as a second layer during a four-day trip to Mt. Ypsilon (13,514′) and Mt. Chiquita (13,075′) in RMNP.

The Merino Air Hoody is designed for warmth and breathability, but I found it too warm for some activities. When skinning uphill and during strenuous approaches, I definitely sweated more than usual. The problem is–and this was especially true when wearing a softshell over the Hoody–was that I’d overheat. And when I took the softshell off, I’d freeze because the Hoody doesn’t block the wind.

When not wearing the Merino Air’s hood over my head, I kept it pulled down around my neck. Since the hood is lofty, like the rest of the top, when the hood was down it bunched up and made me feel claustrophobic. The feeling was like having a boa constrictor’s body wrapped around my neck and I wanted it off, but since the Hoody doesn’t have a zipper, I was stuck with this uneasy feeling unless I took the layer off.

On the plus side, the Hoody kept me cozy and warm during cold days in the alpine, and I never reached for a Buff to add extra warmth to my neck. The Merino Air’s hood fits comfortably under a helmet and protects my chin, mouth and ears from the cold.

The Hoody comes in cinder red, campfire orange, deep sea blue, forge grey and underwater blue for men. It is also available form women in birch white, black, drumfire red, epic blue, forge grey and purple.

Of note: This item is only available for a limited time. A spokesperson at Patagonia said the company is “currently looking for a new merino supplier.”

Pros: Form fitting and true to size; equally functional and fashionable; lightweight; warm; durable–does not pill or pick easily; comfortable–soft and is not scratchy against the skin; anti microbial

Cons: Does not block wind;hood/neck gaiter gets too hot during heavy exertion; limited availability

Mike Lewis, M.A. is an AMGA Certified Rock and Alpine Guide living in Estes Park, CO. Mike has been guiding and instructing for 23 years throughout the U.S. and internationally. Learn more about Mike at