The best way to care for your down sleeping bag? Keep it clean.
Wet down is heavy and can tear if you're not careful. When it's finally time to wash your sleeping bag, follow Daan's step-by-step instructions:
How to wash your down sleeping bag
Handwashing your down sleeping bag
Before washing your sleeping bag, ensure all zippers and velcro tabs are secured.
Fill your bath with 150mm of warm water and add a pure, mild soap, or detergent.
Place your bag in the tub and gently massage the water into the bag by adding pressure from above with your open hands until the bag is saturated. When your bag is laden with water, do not attempt to lift it out because the heavy, wet down may tear the baffles.
Leave to soak for 1-4 hours, depending on how dirty your bag is.
Drain the water and then add fresh water, and massage the water into the bag again. Repeat this process until no suds are visible in the water.
Press the water out of the bag and express as much water as possible.
Fold the ends of the semi-dry bag in towards its center and press firmly until all water is expelled.
Once all the excess water has been released, the bundled sleeping bag can be put in a tumble dryer set on a low setting or air-dried. To air-dry the bag, lay out flat on towels over two portable clothes racks.
Dry in a shaded area out of direct sunlight, as excessive exposure to UV will degrade the shell fabric. A hot, dry, windy day provides the perfect conditions for air-drying your sleeping bag.
To care for your sleeping bag
When new, Kathmandu's down sleeping bags have excellent lofting properties. To help maintain the high performance of your sleeping bag and prolong its life, store your sleeping bag in the large cotton storage sack provided.
Only use the smaller stuff sack or compression sack while on the move. Never roll or fold your sleeping bag, always force the bag into the stuff sack or storage sack with your fist.
To stuff the bag into the small stuff sac, pack it firmly from the bottom. For bags with an e-proof or Pertex® fabric shell, first turn the sleeping bag inside out.
While on your adventure, lay out your sleeping bag as soon as you arrive at your destination to allow the bag to fully loft. A fully lofted bag will provide better insulation.
It is important to keep your sleeping bag as dry as possible. Moisture will affect the insulation capacity of the down by reducing its lofting ability. Take any opportunity to air out your sleeping bag during your trip, and always ensure it is completely dry before storing.
Other important tips:
Don't dry-clean your sleeping bag as the solvents they use can damage the down.
You can reduce the need to wash it by using a sleeping bag liner, spot cleaning marks on the outside with a damp cloth, and by using a sleeping mat.