Primaloft Durability

I haven't seen good data on this. There are two related but different issues (loft lost, and CLO lost) over time. In my experience, it seemed that I lost less warmth than loft (e.g. 50% of the loft was 70% of the warmth). Maybe someone could comment on this.

I have little experience with primaloft sleeping bags. In the mid-90s I purchased patagonia's original puffball vest which was primaloft. My memory is that it lost around 50% of it's loft after around 3 years. I would guess that it was used something like 60 days / year, maybe 3 hours each day on average. Mostly not compressed by a pack, but often under a shell.

"Prima____" means my 1st generation PrimaLoft sleeping bag by Caribou Mountaineering (remember them?)is now merely a "Prima" bag, having lost its "loft" after just two summer seasons of backpacking.

I now stay away form PrimaLoft insulated products. I'd rather have Thermolite as a highly compressable insulation if I wanted to go that way. In fact my knock-off British military insulating layers are made of one version of Thermolite and I have been very happy with their amazing warmth, compressability and ability to retain loft. However I feel Thermolite is best suited for garments.

Currently Climashield would be my 1st choice for a synthetic sleeping bag insulation, summer or winter.

Eric

I have a Primaloft Sport bag that lost a lot of loft in a fairly short time. On the other hand, it doesn't seem to have lost much warmth. I'm not sure how to explain this but it does lead me to question the loft=warmth equation.

Sorry, I should have phrased my original post better. I'm really only concerned about warmth, not loft. Although, I would assume there is some curve for synthetics where lost loft equates to lost CLO values – but not a 1-for-1 loss.