Do all down top quilts ( tqs) understate warmth

**DemostiX** · 01-29-2012, 13:16

I attributed comfort beneath opened summer weight sleeping bags to extra loft from extra width, wool sweaters, and conservative ratings from the makers. Or to being a "warm sleeper."

After a couple of comfortable nights, without the wool, beneath a Hammockgear 40F -rated top quilt, to 22F, I'm not so sure.

I wonder whether the super-adequacy of underquilts is not the source. The notion / hypothesis is that UQ - hammock combinations are unique in sleeping experience. There's no heat sink and heat loss is lower than what most people experience even in their own beds by conduction unless they use lots of insulative padding between themselves and their mattresses.

In my case, the UQ has been a short full-length Hammockgear underquilt, above which I haven't been cold to 10F either.

What seems to make a down UQ work so well is its low mass, not just its resistance to heat flow. If the slightest gap has formed between the UQ and the hammock bottom on a cold night, and I pull the UQ up snug, I can immediately feel a bit of cold from the transfer of heat from my skin to the smallest of heat sinks, the top layer of the UQ. And then, I am immediately warmer.

What is your experience with TQ ratings, sleeping above a properly working underquilt? Do you sleep comfortably under thinner TQ than you expected for the temps?

**dedominick** · 01-29-2012, 13:23

I am interested in hearing about this one!

WV · 01-29-2012, 14:10

While I don't use underquilts and make my own gear and thus can't comment on UQ ratings and such, I think Dx has touched on some important points and raised meaningful questions for all hammock hangers.

**Knotty** · 01-29-2012, 15:42

I'm a cold sleeper but find that my Golite 20F down TQ is accurately rated. Actually I slept in it last night at the NJ Winter Hang and the low was 22F. I also have one of their 40F synthetic TQs and find that I'm cold in it even at 60F. So it seems that the accuracy of the rating can vary from quilt to quilt, even when from the same manufacturer.

In general, I find that it's easier to stay warm in the down version of almost any product. Much of this is probably attributable to the low thermal mass. Secondly I think down products do a better job of conforming to your body than synthetics, making them warmer, but I'm starting to go off topic.

Almost any time I've been cold in my hammock it's been attributable to the UQ. Usually an issue with gaps. For TQs, I think you need to consider them as bring your own head/neck insulation systems for the TQ to meet its rating.

**DemostiX** · 01-29-2012, 18:03

What I've taken too many words to say is:

Why am I not cold even with so little above me? It isn't "toasty" warm under the TQ, but I'm not cold, either. Could it be because I am not being drained of heat from below and can't be drained of it because there's a terrible heat conductor and no mass underneath?

That's the hypothesis.

**G.L.P.** · 01-29-2012, 18:29

i like this.... good points
i will be following

**USMCStang** · 01-29-2012, 20:10

Just throwing this out there. I use a 40 degree rated bag as my TQ. I have taken it to 20 degrees without a problem, and it could easily go colder.

Could it also be that warm air rises, whereas cold air descends? All of the heat that your body is producing is rising to the liner of the TQ, which in and of itself will trap a small amount of warm air next to your body. Alternativley, a down UQ with a gap will vent heat dramatically, thus letting cold air in. Where does that cold air go? The lowest point that it can without resistance, which is generally your butt.

Additionally, thousands of posts on here talk about "fine tuning" your UQ with different suspension techniques, hooks, tieout loops, etc. How many threads are there about fine tuning top quilts? It's basically just "put your feet in the footbox, wrap it around your shoulders, and lie down". It is this inherent simplicity that I for one believe makes a TQ "warmer"...it's pretty hard to get it wrong, whereas an underquilt can be pretty hard to get right.

**TATO** · 01-29-2012, 20:20

I use a 20 degree full UQ and a 35 degree sleeping bag as a TQ. I have been to 23 with this setup and was really warm. I think I could have went another 5 - 10 degrees lower easily before even getting a chill. I agree that getting the UQ adjusted right is the key.

I would like to see a test of just the opposite. 20deg TQ and 40deg UQ to see what the difference is.

**taylo** · 01-29-2012, 21:43

I have no idea, but if you're warm, stick with it. I wouldn't think about it too much. Too many variables and everyone is different. This is going to a long thread probably.
Bottom line, you have something that works for you. Be happy and go sleep outside. Goodnight!!!!!

**Floridahanger** · 01-29-2012, 22:17

DemostiX, at the Florida Hang 2 weeks ago, I used a Walmart summer bag for a peapod without the head end adjusted at all (hanging loose) and my jacket wrapped around the head end of the RL. Also didn't have a tarp. It got to 28-30 and only my feet were cold. I did have a very light and small wool blanket(summer use) over me and yoga pad under me. Only my feet were cold.
I believe the pad took care of all heat loss from under me except where my feet hung past the pad. The air over me was warm since I was covered by the SB and jacket. I too think there is something there to what your searching for. Will stay tuned...