Conventional wisdom has long held that the plumage of waterfowl provides the best insulation against the cold and that the puffy down jacket is standard equipment for mountaineers and urban commuters alike. But down loses its mojo when it gets wet and is not without the controversy inherent with animal-based products. NuDown, a small company based in Reno, Nevada, has an innovative new solution and it might just be better than down: air. Sometimes the best solution is the one that’s all around you. NuDown has introduced an air-insulating parka and vest this winter, and while it remains to be seen whether it will catch on with down devotees, we tried out the Mount Whitney Vest ($350) and came away impressed.
A layer of warmed air traps heat and insulates better than down and does so without the bulk. Cold water divers have been staying warm for decades by filling their sealed drysuits with compressed air, which traps a layer of warmth against their bodies, insulating them from the heat-sapping water around them. If it works underwater, why not on dry land, inside a jacket? But while a diver can use compressed air from his tank to inflate the suit, it’s not as easy with a jacket. NuDown’s Mount Whitney Vest solves this by putting a small hand pump in the front pocket with which the wearer can add air to the chambers inside the vest.
According to NuDown, one squeeze of the pump adds one degree Fahrenheit of warmth to the vest. In our tests, it took about 40 to 50 squeezes to fill the vest to a snug fit, suitable for the chill of a ski outing in a Minnesota winter. And snug is an understatement. In order for air to insulate, it must be as close to the body as possible. NuDown recommends pulling the waist cords tight and zipping the vest up to the neck. When the vest is fully inflated, it feels a bit like getting a firm hug from your grandmother. The resulting appearance of the vest, with its rippled chambers full of air, is not unlike Batman’s padded suit. It took some getting used to. It’s not an unpleasant fit, but it does restrict movement somewhat; however it wasn’t much of an issue while cross-country skiing.
Beyond its innovative approach to insulating, the vest, which was created by two former Patagonia designers, looks and feels much like any other piece of technical outerwear, with a stretchy water-resistant 50-denier polyester face, high collar and mesh lining. The inside of the vest is made of a bamboo and charcoal membrane that wicks moisture and resists odors. Two slash hand warmer pockets zip shut on the front, but the left one is taken up largely by the hand pump and hose, which looks like a home blood pressure tester. With the vest inflated, the pump does feel prominent in the pocket and it is noticeable while skiing. And you can get the Mount Whitney vest in any color you want, as long as it’s Navy blue.
For all its fabrics, styling and tailoring, the real question is: is it warm? The answer is yes. The Whitney was surprisingly effective in 20-degree weather, worn over a base layer and under a light windproof shell. After only a minute or two, body heat warmed the vest to a comfortable level that actually got too warm once we hit the trail. But that’s the other advantage this garment has over down equivalents: it’s adjustable. By pressing a button on the hand pump, air is slowly released from the vest, allowing for infinite fine-tuning of warmth. So once you get up to temperature, you can release a little until a comfortable temperature is attained. When you stop and cool off, you can add some air to the vest to warm up again. No more shedding layers or alternating behind sweating and getting chilled. NuDown also sells an optional argon inflator kit that can be threaded onto the pump to fill the vest with the inert gas, which traps heat even better than air.
We don’t know if air insulation will catch on with the general outdoor crowd. As with any new technology, adoption takes time, and down, wool and Polarfleece have had a long head start. And there is the risk factor that you’re relying on a mechanical pump for your warmth, and perhaps your survival, and pumps can break at the worst times, leaving you cold. That said, it’s great to see brands pushing the limits of what’s possible and coming up with new technologies in outerwear and gear.