UQ Temperature Ratings
I've had my first UQ for 6 weeks and slept with it in place about a dozen times from about 33 to 48* or so....I am very happy with it with the minor adjustments I made at the low end of the temp range.
Various UQ users and some mfrs occasionally claim that their quilt is ''good to 50*" or some other temperature. Some times with a caveat statement like but I'm a warm or cold sleeper or ymmv.
I can & have dealt with other vague or ambiguous advertising in the past.... no problem. Many sleeping bag makers used to be optimistic in their ratings and others pretty close, for example.
BUT This place and the suppliers here are several cuts above others and I would like to understand what these UQ ratings statements assume and mean. More specifically what level of sleeping bag or quilt, night clothing, head, foot and neck wear are assumed.
Is this somewhat standardized?? I suspect not ... so will carry on as wisely and informed as possible as always.
There is a EN testing standard (Europe) for sleeping bags but it would be too expensive for mom & pop shops to send their TQ/UQ to get numbers for.
As a very loose rule of thumb, you can compare the loft of various quilts or the oz. and the fill power [600, 700, 800] of the down.
I have also seen Pan from JRB post before about their quilts. I forget exactly what he said, so maybe he will chime in or you can find the post.
But it was along the lines that at least the JRB quilt temps are very conservative. Meaning that if they don't think it will get everyone/most to that temperature they don't rate it as that.
I also recall him saying something about testing it with just a light base layer.
Hopefully once again Pan or someone else will explain more fully how they may test and rate their gear.
On a side note, that's pretty interesting about the EN testing.
One of the stickies lists the Temp Rating for quilts but again without the assumptions/accessories.
I am empirical by nature == My Initial experiments used a 40* bag with a new design u-quilt that should get well down into the 40's. It did easily (the way I sleep, warm) in Poly Johns and then with a diySPE and NeoAir and neck gaiter and fleece hat, went to near freezing with a light breeze.
This autumn as temps go to 28-35 will add an IX layer with a 30 deg bag and a 20 bag etc for cooler....but this is just a guess.
yeah i think the JRB quilts are rated higher then what they really are...
i know the Hudson river worked great at 7 degrees...and thats a 25-30 degree quilt...
so yeah i think the JRB ratings are very conservative :D
Okay, I am a cold sleeper, and the Hudson River rating is spot on for me. So your own mileage will vary. :)
If you look at a 20 degree Western Mountaineering sleeping bag, you will see a five inch loft - halve that (it's a sleeping bag, there's a top and bottom) and you get 2.5 inches of loft. The Hudson River and its 3 season JRB brethren have 2.5 inches of loft. Western Mountaineering is one of those brands that needs not exaggerate - it's the Lexus of sleeping bags, by the standards of most reviewers conservatively rated, and like our JRB quilts they use high quality down.
So I would say that if a quilt were adequately filled to 2.5" of down loft, it would likely be capable of the same 20-25F rating easily.
Down thickness can generally be used to 'scientifically' predict body protection at varying temps --- aside from certain construction techniques and body variations.
I am looking for similar guidance related to UQ and TQ combinations/thickness which can readily be used for similar predictions.
I am a relative UQ newbie and hammock in cool weather so that my concern is to have adequate insulation underneath.
More underneath and you can get by with a wee less on top ... to a point. Add cloths.
I have a JRB Hudson River as a TQ and it is mighty fine!
I have a Hudson River on top and another beneath. Same thickness in each place. Same warmth. :)
I think it's pretty helpful to look at the comparison chart of the different vendors... For example, StormCrow (HammockGear.com) uses 900 fill down in his quilts, lots of baffles, and more inches of loft result. Loft and fill = warmth, so at the very least you can get a relative sense of how they relate.
If I understand correctly, 800 vs. 900 fill down means the 900 fill expands rougly 11% more, yielding 11% more loft per ounce...
Hope that helps a little... ;)