A sleeping bag is an investment in your comfort and safety on the trail, and like any piece of outdoor gear, it needs regular care to keep performing the way it should. Whether you have a down or synthetic bag, most of what determines how long it lasts and how well it keeps you warm comes down to two things: how you store it, and how you wash it. Get those right and the rest is largely maintenance.
Storage between trips
It’s fine to compress your sleeping bag for the duration of a hike, but storing it in a compressed state at home will damage the insulation over time. I keep mine loosely stored in the large, breathable storage sack it came with, which helps the insulation hold its loft, and loft is what actually gives you warmth. I also keep it somewhere dry and cool, away from direct sunlight, since humidity and dampness can damage both down and synthetic insulation, and prolonged sun exposure degrades either fill as well.
Wash it rarely, and know why
I only wash a sleeping bag when it’s genuinely necessary. Frequent washing breaks down the insulation and reduces performance over time, in both down and synthetic bags, so a stuff sack liner is worth using just to keep dirt and body oils off the bag and cut down how often it needs a proper wash. For minor stains, a damp cloth or sponge to spot clean the area beats washing the whole bag.
When a full wash is actually needed, the machine method is largely the same regardless of fill type, with a couple of differences worth knowing. Use a front-loading machine rather than a top-loader with an agitator, which can crush or damage the insulation. Zip up all zippers first. Use a mild detergent, down-specific for a down bag or one designed for synthetic fabrics for a synthetic bag, since harsh detergents strip the oils from down and can damage synthetic fibres either way. Avoid fabric softeners entirely, as they coat down and stop it lofting properly. Wash on a delicate or gentle cycle at temperatures no higher than 40°C / 104°F, with an extra rinse cycle to make sure all the soap is out, and use a faster or longer spin cycle afterwards to remove as much water as possible before drying.
If you don’t have access to a suitable machine, hand-washing in a bath works as well, though it takes more care. Make sure the tub is clean first, turn the bag inside out, and place it in enough warm water to cover it along with the recommended amount of soap. Knead the bag gently, or use a rolling motion, as if treading grapes, to work the soapy water through the fabric, and avoid picking the bag up while it’s wet since that can tear the baffles or stitching. Drain the tub, squeeze out the excess water gently, then refill with clean water and rinse until it runs clear.
Drying
Down needs to be dried completely to prevent mildew, and I don’t rush this part. A front-loading dryer on low heat, with dryer balls or clean tennis balls to help fluff the down as it dries, works well, but it can take several hours to dry a down bag properly. Damp down loses its insulating ability and turns clumpy, so patience here matters more than it seems like it should.
Synthetic insulation dries faster and is more forgiving, but I still use low heat in the dryer to avoid damaging the fibres, with a dryer ball or tennis ball to break up any clumps. If you don’t have access to a dryer, hanging the bag in a well-ventilated area away from direct sunlight works too, just make sure it’s fully dry before you pack it away. For both fill types, dry in the shade or indoors where you can, since direct sunlight degrades the insulation over extended exposure.
If your bag gets wet in the field
Down needs drying as soon as possible if it gets wet on a trip, because wet down loses loft and insulating power fast and you want to restore it before the next cold night. Hanging it in a dry, sheltered spot or using a portable pump sack to compress it can speed this up in a camp setting. A waterproof sleeping bag liner is worth carrying in rainy conditions for this reason, particularly in Australia’s humid coastal regions.
Synthetic insulation dries faster than down and is more forgiving of a damp night, but it still needs to be dried out properly rather than left damp for extended periods, since that leads to odour and bacterial growth either way.
Repairs
A down bag with a hole or tear can be patched with a down-specific repair kit, and I make sure the bag is fully dry first so moisture doesn’t get trapped inside the repair. Synthetic bags are easier to patch, and most minor tears can be fixed with duct tape or a fabric patch. Either way, repair the bag before storing it, since an unsealed hole only gets worse sitting in storage.
Liners extend the life of either bag
A sleeping bag liner keeps the bag cleaner, adds a bit of extra warmth, and cuts down how often you need to wash it, which is really the main thing that shortens a bag’s working life. It’s particularly worth using in hot and humid climates like Australia’s coastal regions, where moisture and dirt build up faster than they do inland.
