In reply to johnlc:
Good question, and one with no easy answer (and following Frank R's introduction I hope this one lives up to expectations!)
We don't know a great deal about how down degrades or what impacts its lifespan. There are a few absolute no-nos, like leaving down soaking wet for weeks on end or getting it covered in strong base, but in general use we aren't really sure how it degrades beyond 'it eventually breaks down'. If anyone reading wants to do a PhD this would be a very good one.
When down is recycled it undergoes a similar sorting process to natural down and, as linked to above, we only use the best stuff. The washing/sterilising/drying/sorting process is pretty aggressive, far more aggressive than any other process the down will undergo in its lifespan, and if the down survives that intact then I am inclined to think that the recycled down will be durable for a fair while longer. You could consider this a bit like proof testing a karabiner. The 'best' material that we receive looks just like virgin down: it is large clusters with few fibres missing and those fibres are largely not fibrillated or damaged. What's happening on the inside of those fibres? Is the inside where the damage shows? I don't know, and without a couple of electron microscopes it isn't possible to find out.
The down in recycled down could be of any age. It could be from a hotel pillow that is changed every year regardless of use; it could be from a sleeping bag that was brand new but got melted beyond repair on a stove (we see this occasionally); or it could be from an aristocrat's down duvet that has been used for a hundred years. Just because it is recycled doesn't necessarily mean it's particularly old/used.
Recycled down isn't as high performance as the very best virgin down so we don't use it in our highest performing products, but for 99% of people it provides all the performance that they are likely to need. For most down products the reason they stop being used is not the down itself: it's usually zip failures, fabric tears, lack of washing, no longer meeting requirements, etc.. We've been using recycled down for over six years and in that time we haven't, to my knowledge, had a single returned garment/sleeping bag because the down 'wore out' or didn't loft as expected.
In short, we don't know for definite regarding recycled down's lifespan, but it certainly isn't the limiting factor in the useful lifespan of most products.
Matt @ ME
