My sleeping bag isn't lofting as much as it used to

Two of the most common reasons a sleeping bag loses loft are moisture within the insulation and a build-up of dirt, body oils, sunscreen, insect repellent, and salt from perspiration.

1. Residual Moisture in the Insulation

Even if the shell fabric feels dry to touch, moisture can remain trapped deep within the down clusters or synthetic insulation. This causes the insulation to clump together, reducing its ability to trap air and provide warmth.

If you suspect moisture is the cause:

• Ensure the sleeping bag is completely dry before packing or storing it.
• Tumble dry the bag on a low heat setting with two or three clean tennis balls or dryer balls.
• Periodically remove the bag from the dryer and gently break apart any remaining clumps by hand.
• Pay particular attention to thicker areas such as the hood and footbox, as these can retain moisture longer than the rest of the bag.
• Continue the drying process until the insulation feels evenly distributed and fully lofted throughout the bag.

2. Dirt, Oils, and Salt Build-Up

Over time, contaminants from normal use can accumulate within the insulation. These substances coat the down plumes or synthetic fibres, causing them to stick together and reducing their ability to loft. As loft decreases, so does the bag's warmth and overall performance.

Common sources include:

• Skin oils
• Sweat and salt deposits
• Sunscreen
• Insect repellents
• General dirt and grime from camping and travel

In many cases, a thorough wash can dramatically improve loft and restore performance by removing these contaminants and allowing the insulation to expand freely again.

Visit our Blog Post for step-by-step instructions on how to wash your bag. 

3. Storage Practices

Long-term storage can also affect loft, particularly if a sleeping bag has been stored compressed for extended periods.

For best results:

• Store your sleeping bag loosely in the supplied storage cell or a large breathable storage sack.
• Avoid long-term storage in compression sacks.
• Allow the bag time to fully loft after unpacking, especially before a trip.

4. Age and General Wear

All insulation gradually loses some performance over time through repeated use, compression, and washing. However, a significant loss of loft is most commonly caused by moisture or contamination rather than normal ageing.

If your sleeping bag has become noticeably flatter, less warm, or has visible clumping, we recommend first ensuring it is thoroughly dried and then washing it according to the care instructions.