Functional life of insulation

[Will_m]

Does anybody know or have an opinion on the longevity of life regarding insulation in sleeping bags, particularly polarguard 3d?

I have a 15-20 year old bag with it and have suspicions of whether the material still insulates properly. Being that I don't have access to a deep freezer, and it will be several months before I can actually test it, I was curious whether anyone actually knew anything about this type of situation.

 

[colonel00]

Why do you think it no longer insulates? Does it not have the same loft as it used to?

 

[kodiakfly]

Why do you think it no longer insulates? Does it not have the same loft as it used to?

Like Brad said, it's about loft. If the bag is still fluffy, it should still insulate. Many people say that there's a loss of loft with use, age, or storage and there may be. I store my bags loose in mesh bags or hung vertically and even the two 3D bags I have from the same vintage as yours still have their loft. Maybe if they were 0* bags back then, they're 10* or 15* bags now, I don't know....I don't use them any more...but they'll still insulate.

 

[Will_m]

Why do you think it no longer insulates? Does it not have the same loft as it used to?

To be honest, I'm not really sure if it has the same loft or not. I just thought it was a possibility that over time the thin fibers of the insulation would inevitably lose some of their structure and thus, some insulation value.

 

[Ramshead]

Here is an article that may answer your questions. Warning, a bit of a long read, but based on scientific testing by the University of Leeds over a 20 year period. Personally I don't use synthetic bags because I have been able to keep my down bags dry for going on 35 years.

http://www.phdesigns.co.uk/the-truth-about-sleeping-bags

 

[Chem-E]

I have an old North Face with Polar Guard 3D that is from 1995. This bag is still plenty warm.

 

[Will_m]

I have an old North Face with Polar Guard 3D that is from 1995. This bag is still plenty warm.

Wouldn't be surprised if they were the same bag, though I have no way of knowing what mine is as there is no model name on it to be found. Yellow top with a black bottom though.