UQ/TQ Temperature Ratings, and other questions

[KBr00ks]

I'm beginning to consider going from a sleeping bag + pad combo to an UQ/TQ combo. Initial math seems to indicate that there wouldn't be a weight or volume penalty in the switch. BUT -- that's assuming that temperature ratings are relatively equal across the board, a big assumption.

My bag is a 10-year-old REI down bag rated to 25ºF. At the time I bought it, there wasn't an official standard for temperature ratings (I don't think?), but it seemed generally understood that the rating was not for comfort, but for survival. That bag so far has been comfortable, for me, down to about 40º (with addition of wool underlayers and a hat).

So could I expect the same level of comfort with a 20ºF rated UQ/TQ?

I see now that there is some sort of standard for temperature ratings, EN13537, a European standard effective in 2005. I have no idea if my bag would be rated differently with this standard, but comparing current prices and specs, I think it's about the same. But I don't see the common cottage vendors here mention this specific type of rating. (At least the 3 I've looked at so far... and I haven't studied the specs closely, so maybe I missed this.)

A related question... which do you prefer, a full-length UQ or a 3/4 length? If 3/4, do you use a foot pad? (This frankly mystifies me... it sure seems like a full-length UQ would be preferable. That last 1/4 of down quilt would weigh less, warm more, and be much more compressible than a foot pad.)

Thanks in advance for sharing wisdom!

[Boston]

Most cottage down quilts are rated based on actual use, and some assumptions about loft vs warmth. Generally speaking most users report they take them down to their rating, or lower, with appropriate base layers, and under normal circumstances (not dehydrated, etc..).

No cottage vendor has had their gear tested to EN13537 standards as far as I am aware. Particularly because EN13537 doesn't really lend itself to testing hammock systems.

A TQ and UQ will take up more pack space than a S/B + pad. Typically because the pad is either inflatable, and packs fairly small, or can be attached externally to the pack. Down quilts will reside inside the pack.

Traditional 3/4 quilts are my preference, as they seem to require less fiddling to fit right (without gaps). That said in deep winter camp a properly set up F/L is probably more ideal. But i have been comfortable into the teens with my 3/4 quilt and ccf pad

However, your perception of the down-sides may be a bit off.
1) Weight: footpad vs weight of F/L quilt. Realistically it depends on the foot pad, and depends on the quilt. BUT
1a) Consider multi-use applications. Most who use a foot pad also double it as a sit pad. Many also used "frameless" backpacks like the G4 (including myself), and the pad is used as the "frame" for the pack. When taking this into consideration, the pad basically is free weight for use as insulation. I actually usually carry a larger torso length z-fold pad, as it can supplement insulation, or be used in a "go to ground" situation.

[bkrgi]

Take your lowest temp you will be out in and add 10* lower as a buffer and you will be snug as a bug in your cocoon.
The buffer just allows for weather being cooler than predicted and not compromising ones comfort for warmth/safety.

A 20* quilt set is a great place to start covering from 15* (with extra layers) to 70* with no complaints
But general trust the Vendors ratings as being real relative to how warm/cool you sleep

[KBr00ks]

Thanks, guys.

I'm packing my gear via bicycle bags, so no need (or room) for a stiffener. And I've never felt the need for (nor had room for) a sit pad, so that's out.

My bag is only about 600 fill power down (I think...), so it may be comparable to a 800-900 fill power TQ/UQ setup in terms of weight and volume. Still need to do some measuring and comparing.

Interesting that you prefer the 3/4 UQ, Boston... I was wondering how difficult it would be to get a full length to snug up just so.

Another question: if I went with a 3/4 UQ, would the footbox of a top quilt take care of the under-insulation needs of my feet/calves? Or would some sort of pad still be necessary? I'm a side sleeper, if that matters.

[KBr00ks]

Thanks, guys.

I'm packing my gear via bicycle bags, so no need (or room) for a stiffener. And I've never felt the need for (nor had room for) a sit pad, so that's out.

My bag is only about 600 fill power down (I think...), so it may be comparable to a 800-900 fill power TQ/UQ setup in terms of weight and volume. Still need to do some measuring and comparing.

Interesting that you prefer the 3/4 UQ, Boston... I was wondering how difficult it would be to get a full length to snug up just so.

Another question: if I went with a 3/4 UQ, would the footbox of a top quilt take care of the under-insulation needs of my feet/calves? Or would some sort of pad still be necessary? I'm a side sleeper, if that matters.

[OutdoorEnvy]

Good topic.

A similar question I have had that goes with this is: What is the expected clothing layer for the ratings. Like is a 0 degree top and under quilt setup expected you be wearing a layer or multiple layers of clothing as well when it's 0 degrees? and if so how much and what rating should the clothes be? Seems if they give a comfort rating you shouldn't need any accommodating clothing layers for it to perform at that rating.

And yes I realize sleeping commando in the woods has it's downsides and I am not pushing for that, haha!

[Grumpy Squatch]

The standard that covers this kind of testing for sleeping bags, EN13537 specifies that the test dummy be clothed as:

During the test, dummy is dressed in two-piece clothing with specific thermal insulation of material Rct = 0.049 m2K/W ± 10 % and in socks getting to knees with specific thermal insulation of material Rct = 0.054 m2K/W ± 10 %. Face of dummy is covered with face-mask.

At least according to one manufacturer's site. Problem is that the standard is not well adopted outside of Europe, and, few small cottage companies could afford to certify to it. It's really expensive to test and each model must be certified separately. But that gives a clue of what most people (or at least the people who wrote the standard) think a "normal" set of sleeping attire is. Based on some back-of-the-hand calculations using Wikipedia information, that equates to a lightweight set of thermal tops and bottoms and a balaclava type mask. REI confirms this in their FAQ pages:

EN ratings are based on a sleeper wearing 1 long underwear layer and a hat, and sleeping on a single 1"-thick insulating pad

What I understand most smaller vendors do is make a guess based on the amount of insulation (by volume and weight) and then tweak based on personal testing and early customer feedback. But I think most would say that a lightweight thermal top & bottom is the basis for their measurement, at least for quilts 30 degrees and up. For colder-rated quilts I think hats/hoods in addition would also be standard.

Hopefully some vendors will weigh in.

I am a warm sleeper and have slept toasty in my recent 20 degree top/bottom quilt with no overstuff down to 26 degrees with only lightweight thermal tops and bottoms, regular hiking socks, and a fleece hat. Before hammocking I regularly took my 15 degree Sierra Designs bag down to the teens in the same layers with only an old thermarest inflatable pad.

[genixia]

Aside from the financial side of EN13537 testing there is another very practical consideration that makes it all but useless for hammock quilts - it assumes a mummy design with integrated hood. There are no criteria for testing a quilt with a down hat, nor for a topquilt used in conjunction with an temperature-appropriate underquilt. Basically, if a vendor were to try and get a quilt tested they would end up spending a lot of money to have a quilt stuck on a dummy on a 1" pad with no head-wear beyond the face-mask, and the results would not be very accurate. That accuracy would get progressively worse for colder quilts.

Most vendors here rate quilts closer to comfort than survival. You can check most of their specs for weight, size and fill-power to calculate average thickness and plug that into the Jardine formula (or quilt calculator) to check its rating. Between that an user feedback in the vendor forums you should be able to get a handle on how a particular vendor rates their quilts.

[bkrgi]

Good topic.

A similar question I have had that goes with this is: What is the expected clothing layer for the ratings. Like is a 0 degree top and under quilt setup expected you be wearing a layer or multiple layers of clothing as well when it's 0 degrees? and if so how much and what rating should the clothes be? Seems if they give a comfort rating you shouldn't need any accommodating clothing layers for it to perform at that rating.

And yes I realize sleeping commando in the woods has it's downsides and I am not pushing for that, haha!

With my 20* UQ (2oz OS) and 15* SB I am good using a base layer of heavy Merino wool to 27* including a hat. Any lower and I need another layer of clothing on me and have gone to 15* as my low using a heavy second layer ie big fleece hoody.
Personally I like to leave a 10* buffer as my comfort zone with minimal clothing so with my set up 30* is my comfort....any lower I know I need more layers or the Nalgene hot water bottle trick.

It is imperative that everyone test test test and test some more to find there comfort zone with there set up given there weather conditions. Being cold is not conducive to good sleep.

[KBr00ks]

I would also typically be wearing a layer of Merino wool, and possibly a down jacket with hood if it's cold enough. (Camp layer doubling as another sleeping layer.)

Well, the UQ/TQ thing is sounding better all the time. I like the thought of not wrestling with the bag + pad inside the hammock (and sometimes having the foot end stick out the side), but rather being relatively free to turn around, curl up or stretch out.

So... does everyone who uses a 3/4 UQ also use a foot pad?