Cold Underside - Some Questions & Hopefully Answers

**mattnin** · 12-04-2023, 09:14

I just made a new set of TQ/UQ using 7.5 oz climashield apex and slept outside past two nights. The first night, it was miserable. I was absolutely cold and had some bad cold spots around my legs and knees. I called it quits about 3:30 am and the temperature was 35F. I didn't understand why my back was warm but not my legs. Later that day, I asked my wife to feel between the hammock and UQ and apparently I had an air gap between the UQ and my hammock at my knees. My hammock made somewhat of a calf ridge there. It's a gathered end hammock. I also would, at times, get a cold spot on my neck. I then artificially made a neck ridge and I then had an air gap there. So it clicked, anywhere I had a ridge in the hammock there was an air gap and that created a cold spot. I was wondering why my UQ would go from warm to cold and back to warm but now I figured it out, I needed to get rid of my calf ridge and neck ridge however slight they may be. So last night I made sure to forcibly work out the ridges while I slept especially the times I woke up with a cold spot on my neck and my knees/calf area. Also, I tightened up my suspension overall. I slept warm last night and was comfortable and didn't come inside until 6am. As matter of fact, I got hot at some point and even had to kick off the TQ, briefly before I started to freeze again. The overnight low was 38F.

**BillyBob58** · 12-04-2023, 10:18

Originally Posted by mattnin

I just made a new set of TQ/UQ using 7.5 oz climashield apex and slept outside past two nights. The first night, it was miserable. I was absolutely cold and had some bad cold spots around my legs and knees. I called it quits about 3:30 am and the temperature was 35F. I didn't understand why my back was warm but not my legs. Later that day, I asked my wife to feel between the hammock and UQ and apparently I had an air gap between the UQ and my hammock at my knees. My hammock made somewhat of a calf ridge there. It's a gathered end hammock. I also would, at times, get a cold spot on my neck. I then artificially made a neck ridge and I then had an air gap there. So it clicked, anywhere I had a ridge in the hammock there was an air gap and that created a cold spot. I was wondering why my UQ would go from warm to cold and back to warm but now I figured it out, I needed to get rid of my calf ridge and neck ridge however slight they may be. So last night I made sure to forcibly work out the ridges while I slept especially the times I woke up with a cold spot on my neck and my knees/calf area. Also, I tightened up my suspension overall. I slept warm last night and was comfortable and didn't come inside until 6am. As matter of fact, I got hot at some point and even had to kick off the TQ, briefly before I started to freeze again. The overnight low was 38F.

Hey Mattim: That is a great post and should be informative and helpful for any one who has had problems with UQs. And there have been quite a number of those folks over the years! But you have nailed the essential problem IMO: Some sort of gap or draft that develops somewhere along the length of an UQ, maybe immediately or maybe after a person moves in their sleep or at any time. And as I have repeatedly claimed(again, based only on my experience, so grain of salt) particularly problematic when a full length UQ is used on a gathered end hammock, while laying on a diagonal across the center line of that full length UQ. Lots of POTENTIAL problems to be had with that combo.

As I have oft said: I have never had any problems reaching rated temps or below with my UQs(full length or short) from our high quality vendors using them on the appropriate sized bridge hammock.(caution regarding a too long UQ for the particular hammock though) So, guess what a bridge hammock lacks compared to a GE hammock? Center ridges! The same thing that defeats calf ridge/pain problems with a bridge ends up working great with a rectangular UQ.

I'm glad you ended up warm with that 7.5 CS UQ. One of my all time fav UQs was the very 1st run of the WB Yeti short UQ, which has removable layers of CS. Anywhere from 2.5 to 10 oz(that is what it came with). Both my son and myself have had great success using the less than maxed out layers down into the 20s. I once used just the one permanent layer of 2.5 oz to be plenty warm down into the mid-high 40s! Using no other layers under me other than cotton jeans and shirt.

But, that UQ only goes a short distance past my butt and to my shoulder/neck line. So, once adjusted correctly, guess what that is totally lacking, at least for back sleeping? Calf (or other) ridges. No UQ interfering ridges even on my GE hammocks! With a short piece of CCF(or a pack) providing all of my leg insulation, when needed. With that pad sometimes in the footbox of my TQ. The ex member and moderator Grant/Cannibal (RIP) had used that very same model to below zero for plenty of warmth for his hot sleeping self. I'm certain that the down Yetis work as well or better, but the point is: if the fit is right, there should be no trouble staying warm with 5, 7.5 or more oz/sq/yd Climashield. As you have just demonstrated by figuring out how to defeat your GE hammock ridge caused gap problems! Gaps can defeat any UQ, no matter how thick! Again, good post! " As matter of fact, I got hot at some point and even had to kick off the TQ, briefly". GOTTA LOVE IT!

**unicornv007** · 12-28-2023, 12:17

Originally Posted by BillyBob58

I don't really know why I advocate in favor of pads(much like I used to advocate for the HH Super Shelter with it's wrap around open cell foam pad outside the hammock). Except in my 90º hammock with it's pad pocket, I have not used or needed one in years. (but boy does a pad work well in that one hammock! Also pretty well in my bridge hammocks ) Actually, the last time I used one in any form was in the TQ foot box, because I lacked confidence of my SG Insulated 30F hammock at well below 30F, plus additional wind chill. But, after a couple of hours, I woke up significantly over heating and about to start sweating. So I had to remove that foot pad and some other layers including my hood. But, though I always have them as an emergency back up, I rarely use pads.

I keep trying to work the pad angle because I do want to attempt a Thru-Hike on the AT in a few years... and I'd like the ability to flex between shelters and hammock based on the weather and my mood. I did have the "luxury" of two trips through the Smokies last spring - one where we stayed in shelters only and the other where we used hammocks only. Definitely preferred the hammock by far but in the event we have really bad weather, being able to take refuge in the shelter would be nice. I think that's coming from having one hammocking trip where we had 50 mph wind gusts and my tarp turned into a sail (thankfully, only had to replace a few broken shock cords and spend 20 minutes looking for flung stakes).

Anyway, back to pads. I did manage to build a hammock stand in my office (wife wouldn't let me drill holes in the walls). I've been able to hang in there for relaxation and now I'm trying to play with pads to see if I can get that to work. I think the main issue I have is I'm a side sleeper and even the wider 25" pad (yes, at about 1/3 inflation level only) just isn't wide enough for me as things like knees, shoulders, etc become exposed too easily and its really hard to keep the pad at an angle to get the right lay (I'm a pretty active sleeper). I do have a new TQ ordered for this year which is wider that may help but its hard to say for sure. Either way though, I can "open the window", let the cold air in but keep the door closed, play around with sleeping there for an hour or so... close the window, head upstairs and call it a night while I experiment. If I can't figure it out... then I'll just have to stick with underquilts and if I want to deal with the weight penalty of a little over a pound, then bring the sleeping pad as a bonus item. Hate the extra weight but (might) be worth it in a few sections.

**BillyBob58** · 12-28-2023, 13:41

Unicornv007: "and I'd like the ability to flex between shelters and hammock based on the weather and my mood."
And sometimes per park requirements though I don't know how that works on the AT. IOW, sometimes authorities in some places insist you stay in a shelter. If that happens, or if your quilt gets wet, or if something goes wrong and you are forced to ground or shelter for any reason, a pad can be salvation. Uncomy compared to hammocks? YES! Uncomfy and COLD compared to shelters or ground with no pad? NO! Much, much better than no pad if you are ever forced to NOT hang for any reason.

But, if you can't find a way to use a pad with reasonable comfort in your hammock, either by itself or at least to augment a lighter UQ, then "If I can't figure it out... then I'll just have to stick with underquilts and if I want to deal with the weight penalty of a little over a pound, then bring the sleeping pad as a bonus item. Hate the extra weight but (might) be worth it in a few sections.".

Yep, you have it figured out. Those are your choices unless you just want to gamble that you will never be forced to ground, as many people do and almost always get away with. On all of my longer trips(4 to 7 days) which take me far from my car, I have always taken a pad as back up, but never used it except for 2 nights of my 1st weeks trip way back in Sept 2006. Although, if I had always slept where I would like to have slept (above timberline), I would have needed that back up pad more frequently. But as much as I love camping under the stars above timberline in the Rocky Mountains, I always chose to drop back down in elevation enough to have trees and enjoy the luxury comfort of my hammock. So I sometimes gave something up, that I really liked, to sleep in that hammock. But, I still had a pad for backup.

Unicorn: " the main issue I have is I'm a side sleeper and even the wider 25" pad (yes, at about 1/3 inflation level only) just isn't wide enough for me as things like knees, shoulders, etc become exposed too easily and its really hard to keep the pad at an angle to get the right lay (I'm a pretty active sleeper).".

You would probably benefit greatly from the previously mentioned, no longer available Speer SPE as I've mentioned earlier. Can you sew? It would probably be a relatively easy product to make. It is lighter than a double layer hammock, and works better than most. With part of it's bottom layer being made of non slip ( like under rugs ) material, it will not move! And it is more than wide enough for me (6'1", broad shouldered) in any position.

Sorry if I have already posted this in this thread, I know I have in several other threads. But maybe you can see why this has always been wide enough for me in any hammock I have tried it in. In this case, a JRB James River bridge hammock. You can also stuff those sleeves with clothing, but usually with CCF cut outs:

I have also found my 25" wide TR Neoair to be just barely wide enough(and plenty comfy) in my 90º and bridge hammocks. But if not, I would probably add little CCF cut outs(placed inside clothing) for problem spots such as a knee. 25" wide Neoair in JRB James River bridge(stays put even without SPE or pad pocket!):

I don't seem to have a picture of me sleeping fetal with the Neoair pad in my HT90º hammock, but the width works just about the same as with my bridge hammocks. In this pic, the pad is zipped up inside the deep pad pocket, and is just barely wide enough for knees, feet and butt when I go fetal, or for elbows if sleeping on my back. It never moves and works fantastic, no UQ needed. I have to rate it at least equal in over all comfort to any of my hammocks with an UQ. Now that this company is long out of business, I wish one of our cottage industries would start making these! (It is a bit different from an Amok, does not require a pad)