QUESTION
What are the best conditions to use a synthetic sleeping bag vs a down one? Can you always use a down sleeping bag as long as you keep it in a dry waterproof bag?
ANSWER
The answer is very dependent on the prevailing weather conditions where you are active, and what your budget is
Synthetic
Advantages:
- Lower overall price.
- Maintains thermal properties when wet.
- Does not reduce loft in high-humidity/ sweaty sleeping conditions.
- Easier to clean.
Disadvantages:
- The loft does not last as long as down (3-5yrs vs 8-10yrs)
- Does not compress as small as down.
- Higher weight to loft ratio. (Compared to 650+ down fill)
- Retains smells more than down.
Down
Advantages:
- Very warm for the weight.
- Long life of product.
- Compressibility.
- Distribution of insulation is near equal over the bag surface.
Disadvantages:
- Price is higher than synthetic (50-100% for same temperature rating)
- Cleaning and maintenance. (Special soap, washing, and drying)
- When wet the loft is practically useless.
- Absorbs some moisture from the body during sleep.
Overall
Given that I have used both styles, and love them both in different conditions I would say make your decision after considering the above and speaking with local experts who have used the product in your climate area. Knowledge from a local makes all the difference.
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