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Restoring insulating ability in a synthetic jacket

Original Post
SinRopa · · parts unknown · Joined Sep 2013 · Points: 30

I've read that over time, synthetic insulated jackets can lose much of their insulating ability. I've also heard that this can be restored through some combination of washing and drying. Does anyone have more info on this?

How much of a jacket's insulating ability gets lost over, say, a 10 year period? How much can be restored with a wash and dry?

Gavin W · · Surrey, BC · Joined Feb 2015 · Points: 183

Down and synthetic jackets both "pack out" during extended use, but for different reasons. For down jackets, dirt and moisture cause the down to clump together and not loft properly: this can be fixed by washing with a down-specific wash and tumble-drying low with a few tennis balls tossed in the dryer to help out.

Synthetic insulation loses loft because the fibers break down, so there isn't really anything you can do about that. I would estimate that after about a year of average use (less if you wear your jacket around town, in the car, etc) your insulated jacket loses 50% of it's insulating value, and that can't be recovered. So, a good reason to not be picky when it comes to synthetic puffies and just buy what's on sale.

Nick Sweeney · · Spokane, WA · Joined Jun 2013 · Points: 656

My Atom LT (synthetic soft shell) has lost a lot of insulating ability, to the point that it is really only a fair-weather jacket now. To be fair, I have worn it on every big climb I've done over the last two years and wear it around town 3-5 days per week for three seasons out of the year. I'd conservatively estimate that it's seen 200 days of use and is still kicking, but the lost insulating ability means that it is due for replacement.

Brian Abram · · Celo, NC · Joined Oct 2007 · Points: 498

Short fiber synthetics: 30% loss after a few weeks and a total of 50% loss after a few months of regular use. Arc'teryx says Coreloft can be destroyed in 2-3 months by wearing your jacket while driving 1-2 hours per day.

Continuous fiber: 40% loss after 2 years

See here:…

At the link above they tested a new Rab Xenon (Primaloft One) and then tested it after a 3.5 week backpacking trip. It lost 47% of its insulating value.

Most of the loss is permanent. I've never seen anything showing significant repair of synthetic loft from washing.

The loss in insulative value is somewhat independent from the amount of actual loft left. Just as you can have two different insulations with the same loft have differing insulative values, you can have a worn out Primaloft One jacket with 80% of its loft but only 40% of its original insulating value. The fiber structure is as important as the amount of trapped air.

10 years? Lolz. You're gonna have folks swear their 6 year old well worn synthetic jackets are as good as new, and those people are wrong. If they actually did comparison testing on a hot plate they'd see how much their jackets have degraded.

A few synthetics are made similarly to fleece. Polartec Alpha is similar to Thermal Pro fleece. Thermal Pro and other fleece insulation does not degrade the same way as synthetic puffy insulation, and it does recover some if not all its loft via washing, drying, and shaking out.

Nick Drake · · Newcastle, WA · Joined Jan 2015 · Points: 483
Brian Abram wrote: 10 years? Lolz. You're gonna have folks swear their 6 year old well worn synthetic jackets are as good as new, and those people are wrong.
Only comments I've ever heard from friends with 5 year old 60-100gr synthetics on climbs was, "holy shit I'm cold!" :)
Guideline #1: Don't be a jerk.

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