– Don’t dry-clean a down sleeping bag. The dry-cleaning chemicals strip the oils from the down and prevent it from lofting properly.
– Use soap specifically formulated for down. There are a number of such products from leading available; a good outdoor store will have them in stock. Regular laundry detergents will also strip oils from down.
– Do not use a top loading washing machine. The mechanical action of the impeller (the plastic spiral in the drum) is far too rough for a sleeping bag.
– Either use a front loading washing machine on a gentle cycle or hand-wash your sleeping bag.
Hand wash: it’s best to use a bathtub – turn the sleeping bag inside out, place it in the tub and add warm water (enough to cover the bag) and the recommended amount of down soap. Gently knead the sleeping bag to force water/soap through it. DO NOT PICK UP THE BAG DURING THIS PROCESS. When the sleeping bag seems clean, drain the bathtub and then carefully roll up the bag to squeeze the water out. Turn bag right-side out. Refill the tub with clean water and knead the bag to force clean water through it – continue until there are no more suds. Carefully roll up the sleeping bag again to squeeze the water out of it.
Machine Wash: select a delicate wash cycle with a temperature setting of no higher than 40°C / 100°F with an extra rinse cycle. Select a faster/longer spin cycle – it is important that as much water is spun out of the bag as possible before you attempt to remove it from the drum. Whether you hand wash or machine wash, DO NOT pick up the sleeping bag when it is full of water – the weight of the water in the down may tear out the internal baffles.
– Tumble dry. Put the sleeping bag in the cotton laundry sack before putting it in a tumble dryer. Set the dryer to low heat or ‘delicates’ and run a complete cycle. Remove the sleeping bag in the laundry sack and turn the sleeping bag inside out. Return the bag to the laundry sack and put it back in the dryer. This time, put one or two clean tennis balls into the drum with the sleeping bag – they will help to break up clumps of down. Repeat these drying cycles until you are absolutely certain that the down is dry through and through – if the bag is put away even slightly damp, mold or mildew can form. If you can feel clumps of down, the down is not dry yet.
– Air the bag before storage. Hang the bag up in a dry place where it can air out before being returned to its zippered storage cube.
If you follow the above instructions, it’s relatively simple to get really good results. Bear in mind that you won’t need to wash your sleeping bag as often if you use a sleep bag liner (click here to find out more about liners).