January 26, 2001


Why doesn't anyone make a superlight Primaloft sleeping bag?

I keep hearing that Primaloft is nearly as light as down yet performs better when wet than other synthetics. So, it seems then that someone such as Western Mountaineering could finally put out a 1-pound, 10-ounce synthetic sleeping bag, but they don't. If Primaloft is such a great alternative to down and other synthetics, how come so few manufacturers are using it?

— Jeff Cook Denver, Colorado

Like most synthetic fibers, Primaloft does indeed perform much better than down when soaking wet. In fact, wet Primaloft will retain more than half its insulating ability, compared to a figure of near zero for down. Primaloft is said to be even better at that than competing synthetics such as Polarguard, although as with most claims that relate to outdoor products' performance, that perhaps should be taken with a small grain of salt.

Still, I do prefer Primaloft over Polarguard. I think it's softer and stuffs better, and if it does indeed work better when wet, then that's a bonus. There have been questions raised about Primaloft's durability, but manufacturers who know how to work with the stuff —- Integral Designs comes to mind —- report few problems.

So why isn't it more ubiquitous? In a word, marketing. Polarguard, although no longer manufactured by the big Hoechst-Celanese conglomerate, always has had more marketing clout behind it. That helped it get into the lines of such well-known sleeping bag makers as The North Face, Sierra Designs and Mountain Hardwear. They in turn make the name Polarguard more familiar to consumers, who of course then request it by name. It also helped that Polarguard became known for its durability, a subject which proved the downfall of 3M's LiteLoft, a once fierce competitor. Don't get me wrong —- I think Polarguard is a good product. It's just that it has reached a dominant position for reasons other than its quality.

As for Western Mountaineering, they make down products only. When you start to fool with synthetics, marketing and manufacturing get complicated for a specialized gear-maker. Besides, they're down bags are so darned good, there's no reason for them to try anything else.

So, in your quest for a superlight synthetic bag, try this: Get an Integral Designs Andromeda Strain ($170). It's a fine bag -— rated to 40 degrees (that's a bit conservative, I think), very packable, and weighs 1 pound, 14 ounces. Not your 1 pound, 10 ounce target, I admit, but Primaloft still remains a bit heavier than down to achieve the same insulation goal.