Down has the highest warmth-to-weight and warmth-to-packed size ratio of any widely available material. And quality items made from it can last for decades. If you take care of them. Here's how.
We spoke to Heidi Allen at Nikwax, which specialises in treating, cleaning and conditioning outdoors gear. Heidi used to be a climbing and whitewater guide, so knows about performance in the field and, one year, was tasked with running the company's refurbishment program, so has cleaned and revived hundreds of sleeping bags, jackets and the like. If anyone knows how to take care of down, it's her.
"The first step is to admit that your gear has a problem," she says. "Then clean it. Then waterproof it."
"Dirt and bodily sweats and other gross things get onto the down and cause it to lose its loft and begin to clump," explains Heidi of why it's important to regularly wash your down garments. The chaotic shape of a feather's vanes and barbs is what holds them apart, creating loft and trapping air. And that trapped air is what provides insulation. Down's unique ability to loft so greatly from so little material is what makes it so effective, so anything that compromises loft, compromises performance.
"Another thing that is kind of interesting and gross is that little microbes love to eat the natural sweats and oils that we humans leave behind. So, over time, if you don't wash your gear, then those little microbes can actually eat it away. Particularly the seam tape on your shells. Those same sweats and oils can also clog up the breathability of technical fabrics."
"It's interesting how terrified people are to clean their outdoor gear, but it's really straightforward." We asked Heidi to walk us through the process. "When you clean anything that's down, the important thing is to use a front-loading washing machine. You do not want to clean it in a machine with an agitator. That can bash up the feathers and the garments are usually pretty delicate; an agitator can shred shells and baffles. You can use cold or warm water; I wouldn't use hot. The care label on the item should tell you what the particular garment can handle."
Can you use a regular detergent? "Detergents are a tricky thing both for down and water repellancy," Heidi explains. "Any sort of detergent is going to leave behind residue that attracts water, which is the opposite of what you want in a water repellant jacket and is also not what you want with down because you want down to loft. Detergents are also really harsh on down, they can strip away the natural oil on feathers, which can cause them to become brittle, break and lose their loft."
Instead, Heidi recommends NikWax's Down Wash Direct. "It doesn't strip the natural oils, so it maintains loft and it doesn't leave behind any residues that will attract water. It also has a little water repellency built into it, so for untreated down, it can add some water repellency or for the new waterproof downs, it will maintain their performance."
How often should you re-apply a durable water repellant coating to down and shells? "Between every three and five washes," she recommends. "We say that, if after you clean and dry it, if you splash a little water on your stuff and it soaks right in rather than beading up, then that's a good time to re-waterproof."
One thing that I learned during our call was that you can add a waterproof coating to otherwise non-waterproof down. This will be a boon to people seeking to improve the performance of an older piece of gear they already own or budget shoppers looking to add the ability to insulate while wet to a cheaper down item from brands like Uniqlo or Land's End. Without a waterproof coating on the feathers, down will clump when wet, losing its loft and insulation. As Chris Mills found out when he jumped through ice into a frozen lake, down treated with a waterproof coating retains much of its insulation.
And you can add that ability to any item of down gear for the price of a $US12 can of Down Proof. That will coat both the feathers and the shell with a DWR, making both water repellant.
After you've washed your down and washed in the Down Proof, how do you dry your gear without damaging it? "We recommend throwing it in the dryer on low, low, low heat," says Heidi. "You'll have to dry it a long, long time, but that's the best thing to do. The best practice is to put it through the washing machine's spin cycle an extra time or two to get as much water out as possible first. And then, when you put it in the dryer, put in a couple of clean tennis balls too. That helps break up any clumps that have formed during the washing process."
"When you pull your stuff out of the washing machine, it will look so flat that you'll be like, 'Oh my god, I ruined it!' But, two, two and a half hours in the dry with the tennis balls and it will be super happy again."
You can also hand wash down products if you don't have access to a washing machine. But can you air dry them? "You can air dry down, but it will take forever," explains Heidi. "Give it massages like every hour to break up clumps, shake it out, then spread it back out. it's a really intensive process, but you can do it. As it's getting closer to dry, you can hang it and whack it with a tennis racket to fluff the feathers."
What happens if you don't take good care of your down? "If someone has like a really, really, really old sleeping bag that they have been using for many years, it can get dirty enough that when you wash it, you effectively just was the dirt and oils into the down. There's so much that it just doesn't get washed out. And, when that happens you can see a significant reduction in the loft of the item. Regular maintenance is important, you don't want to get to the place where there's no going back."
And what can you do in the field to preserve down as long as possible? "One good thing to do, if you can, is use a sleeping bag liner," Heidi acknowledges the space and weight penalty, but a liner will keep your oils and grossness out of the feathers. Wearing your base layers to bed will do the same, so long as they're clean, and will add a welcome dose of extra warmth. That's what I do.
Heidi also warns of the need to store down uncompressed between trips. "Don't leave your sleeping bag stuffed in its stuff sack. Hang it up or store it in a nice cotton storage bag. Keeping it compressed is not a good way to keep down happy."
You also need to make sure down has a chance to dry out completely after each use. "I always turn my sleeping bag inside out, unzip it and hang it over a door," suggests Heidi. "Mildew can actually form on down if you put it away wet."