Getting a cold back with an UQ

[mr tickle]

Hey.

My last two long distance trips sucked a bit for the reason in the title. Both scenarios where different so i am hoping i can outline each one with a brief description of the relevant kit i used precisely and allow you to draw your own conclusions opposed to me suggesting them.

Scenario 1:

DIY underquilt - not very good, thin and bulky old school synthetic
Under hammock weather shield
Tarp set in porch mode
Densely packed, albeit young trees.

It was a fairly warm day for autumn, not too windy although there was a steady, chilled breeze. I was cosy until i went to sleep. Sleep was intermittent due to cold spells and by around 4-5 am, maybe earlier my back was constantly cold. It stayed that way until i got up because i got soaked in dew.

Scenario 2:

Snugpak underquilt - Modern synthetic, well reputed.
Under hammock weather shield
Tarp set in porch mode
Lightly packed, tall spruce area.

It was a fairly warm day for autumn albeit colder than scenario 1, the wind really picked up at night and it was a cold wind. The wind was steady with powerful gusts coming in. I was cosier than scenario 1 by far until around 4-5 am then only my back was cold, colder than scenario 1. It did not stay this way.

I don't pull my underquilt too tight so as to avoid compressing the insulation but always check it is not hanging with big gaps. Not sure if the weather shield is fully breathable, but it's definitely waterproof.

I thought my new insulation would solve it, but nope. I don't like closing my tarp unless i absolutely have to. I really want to avoid this i like the scenic wake up's and can't shell out for a cuben fibre tarp.

Any ideas what i am doing wrong? Hoping to iron this out for my next trip in November

Cheers and take care, Stu

[BillyBob58]

You say you don't know if your weather shield is breathable. Are you getting any condensation?

Are the UQs rated for the temps you are in, especially with wind chill?

Is your quilt suspension a perimeter/surround style or does it just attach to loops at each quilt corner?

[mr tickle]

You say you don't know if your weather shield is breathable. Are you getting any condensation?

Not that i noticed, i presume 'scenario 1' was dew, but it may have been condensation. I was soaked.

Are the UQs rated for the temps you are in, especially with wind chill?

Probably. Snugpak simply state it as a 4 season item. It is a climashield style proprietary insulation, off memory iro 1" thick fully lofted (very ball park, it may be thicker actually max an extra half inch). I think on another thread where we discussed synthetics you mentioned 1.2" may be 5oz/sq yd. I would ball park it as near to that, it is a very similar style of insulation.

The temperature forecast for scenario 2 was 12C (54F). I didn't even look at what the predicted wind chill factor was for my trips because i presumed my weather shield was going to take the brunt of the wind, or was supposed to. Are they meant to allow wind through?

Is your quilt suspension a perimeter/surround style or does it just attach to loops at each quilt corner?

The snugpak [scenario 2] has shock cord along the entire length that is supposed to clip to either the trees or tarp ridge to pull it high on the sides of the hammock, it actually sits higher than my hammock slightly. It also has two more centred fixings on each end that clip to the hammocks suspension opposed to a drawstring. It is not rectangular either, it is like an american football or rugby ball. Best give an example really:
http://www.outdoorgb.com/p/snugpak_h...underblankets/
https://www.hammockforums.net/forum/...ad.php?t=33712

You can maybe make out the fold on the underside at the ends, that is the central fixings i mention.

My diy one [scenario 1] was a typical corner fixing item with drawstring to close the ends.

Is that information any use?

Thanks Billy

[mr tickle]

I have been out on other trips aside from those mentioned, with similar weather to scenario 2 and not had a cold back with the Snugpak quilt.

I had the UQ tighter, although i thought it was too tight as i had to jam my hand between the layers. The wind also had to buffer though a hedgerow.

Stu

[Bubba]

Tightening the suspension shouldn't really affect the loft. I find it needs to be very snug to eliminate gaps. You could try an underquilt cover to block wind.

[Detail Man]

If the UQ isn't snug to your body, cold spots can happen. Shock cord suspensions can relax over time, especially in colder temps, smaller diameters being more prone to this. I found Hangnout's method to be very helpful in eliminating cold spots. http://www.youtube.com/watch?v=l-GftNcCvrE I attached mitten hooks to my hammock ridgeline with small prussicks rather than the triangle.

If you sweat a lot at night, especially with a waterproof UQ protector, you may be trapping enough moisture that your body heat can't keep warm, hence the cold spots. UQ protectors work by blocking wind to minimize the windchill, and by being another layer for dew/fog to form on rather than directly on the UQ. Try a fogless, calm night without it and see what happens.

I put a piece of tyvek/ground sheet directly underneath my UQ on the ground to keep moisture from coming out of the ground and dampening my UQ. YMMV, but I think it helps.

On foggy, windy nights I find a hammock sock does wonders.

[Fire-Bug]

DIY corner triangles can help raise and angle an UQ to help eliminate those "unseen", but felt gaps. Additionally, Dutch carries a number of light weight options that aid in this as well, like his quilt hooks and ridgeline quilt hooks - that's what I use. Sometimes a quilt's suspension just isn't sufficient enough to eliminate all the gaps.

[BillyBob58]

Not that i noticed, i presume 'scenario 1' was dew, but it may have been condensation. I was soaked.

Some UQ protectors/weather shields are waterproof/vapor barriers(VB) and not breathable, like an HH Super Shelter for ex. If you don't need use a VB very close to your body and warm, you will end up with condensation in your insulation. Now you say you were "soaked", so no wonder you were cold! Now to figure out why you were soaked! Even a lot of dew on the outside of Climashield style insulation should not have got through that to soak you. That makes me wonder if it was condensation? Way more likely if your weather shield is not breathable.

The temperature forecast for scenario 2 was 12C (54F). I didn't even look at what the predicted wind chill factor was for my trips because i presumed my weather shield was going to take the brunt of the wind, or was supposed to. Are they meant to allow wind through?

A good weather shield should keep the wind out.

The snugpak [scenario 2] has shock cord along the entire length that is supposed to clip to either the trees or tarp ridge to pull it high on the sides of the hammock, it actually sits higher than my hammock slightly. It also has two more centred fixings on each end that clip to the hammocks suspension opposed to a drawstring. It is not rectangular either, it is like an american football or rugby ball. Best give an example really:
http://www.outdoorgb.com/p/snugpak_h...underblankets/
https://www.hammockforums.net/forum/...ad.php?t=33712

You can maybe make out the fold on the underside at the ends, that is the central fixings i mention.

OK, one possibility with a suspension that surrounds the entire quilt is the accordion effect. Where no matter how tight the suspension is, the quilt can still slide- as designed- and move along the suspension, and the head end and/or foot end of the quilt can move towards the middle of the quilt, causing a gap and cold. If this is the case, there are mods you can do to help, which will pull on the quilts from the ends, stopping any accordion effect. That might help, or not.

My diy one [scenario 1] was a typical corner fixing item with drawstring to close the ends.

Is that information any use?

Thanks Billy

You're welcome, and yes it is of some use. We know you were wet, no way to be toasty with that, or unlikely at least, to be as warm as you could be. Now, to figure out why you were soaked. And we know you have a perimeter style suspension, which can sometimes be a problem. So right there are two possibilities.

I have been out on other trips aside from those mentioned, with similar weather to scenario 2 and not had a cold back with the Snugpak quilt. I had the UQ tighter, although i thought it was too tight as i had to jam my hand between the layers. The wind also had to buffer though a hedgerow.

Stu

OK now, here is another part of the mystery: you have been warm with the same gear at similar temps! So, it probably is not the quilts. Maybe it is because you were wet, or because there was a suspension related gap these last trips, or because the quilts were too tight compressing insulation. Was the quilt tighter on the trips where you were warm or when you were cold? Do you know if these quilts have what is called a differential cut, or not?

Tightening the suspension shouldn't really affect the loft. I find it needs to be very snug to eliminate gaps. You could try an underquilt cover to block wind.

I also do better with fairly tight quilts, but like you, I have mostly differentially cut quilts. If a quilt is not dif cut, you need to be just as careful not to snug it too tight as you do to make sure there are no gaps, has to be about just right. If no dif cut, it is much easier to compress loft if the quilt is really snug against your back.

[mr tickle]

My apologies for the delay, i got hammered with work while feeling exceptionally ill over the past few days ><

Also apologies for the lack of information in my first post. I did include every little detail but the wall of text was huge and discouraging so i removed a massive amount of it. I shall expand a bit below, hopefully this time without missing further important detail.

Try a fogless, calm night without it and see what happens.

Not much chance of a low humidity, calm night for a good few months now by the looks of things here

On foggy, windy nights I find a hammock sock does wonders.

I have been using my weather shield in the same sense, however this brings a good point. I am after a full sock if anyone knows where i can get one in the UK? (the only full 'socks' i can find are actually python skins)

If you sweat a lot at night, especially with a waterproof UQ protector, you may be trapping enough moisture that your body heat can't keep warm, hence the cold spots.

I don't think it is to do with sweat, it didn't feel or smell like sweat when i was wet. Furthermore waking up knowingly moist only pertains to one of the scenario's. I may be wrong.

Now, to figure out why you were soaked

I presumed this was dew however i will explain why: It has been very humid in the UK lately, the day this happened it was a fairly warm, very sticky day and i just figured it must have hit dew point in the early hours when the chill came. When i say soaked i should clarify my skin was soaking wet, everything else was just moist, including my clothes which where draped on my suspension. Thinking about it i would have thought condensation would be confined inside the hammock area. What you say later in your post would make total sense to me otherwise (RE condensation with weather shield)

I could well be wrong though. I won't have any way of telling if my weather shield is breathable until tomorrow as i store my gear at my folks house, they live near all the good walks. I will be sure to check.

OK, one possibility with a suspension that surrounds the entire quilt is the accordion effect. Where no matter how tight the suspension is, the quilt can still slide- as designed- and move along the suspension, and the head end and/or foot end of the quilt can move towards the middle of the quilt, causing a gap and cold.

It can't slip easily by design, aside from the perimiter cord there are two fixing eyes at the centre of each end. These tie directly to the suspension via shock cord. There is a small chance the cord could slip through the toggles i guess, i will check this to be safe

OK now, here is another part of the mystery: you have been warm with the same gear at similar temps! So, it probably is not the quilts. Maybe it is because you were wet, or because there was a suspension related gap these last trips, or because the quilts were too tight compressing insulation. Was the quilt tighter on the trips where you were warm or when you were cold? Do you know if these quilts have what is called a differential cut, or not?

I change into dry base layers and grab a hot meal before bed, so that 'should' rule out me carrying moisture other than respiration into my hammock. I think i do breath into the side of my UQ though, i tend to stuff my face in my bedding.

The quilt was tighter on the nights i was warm, although the warm nights also had no strong cold winds.

Neither are differentially cut, i loosened them as trial for winter as i thought they would be obviously too tight given i struggled to get my hand between the layers Unfortunately as a UK resident if i want a diff cut quilt i am going to have to make one, which is beyond my current skill level (my diy quilts where massacred from sleeping bags), beside my machine is bust atm.

If the UQ isn't snug to your body, cold spots can happen. Shock cord suspensions can relax over time, especially in colder temps, smaller diameters being more prone to this. I found Hangnout's method to be very helpful in eliminating cold spots. http://www.youtube.com/watch?v=l-GftNcCvrE I attached mitten hooks to my hammock ridgeline with small prussicks rather than the triangle.

Looking at this video i am doing a few things wrong, i have fitted mine as he says not to (RE point of suspension). Furthermore by the description given in the vid i also currently hang it too loose, it also confirms i used to hang it too tight (RE cold spots being located on pressure points or not).

I will try mounting the suspension as per the video/suggestions in this thread and having it set just a little tighter than present to see if that produces any good results.

--------

Just to summarise what i should check on my 'test' trip through next week:

I will try the suspension method in the video.

I will tighten the UQ, although not as tight as i used to have it.

I will check the fabric on my weather guard to see if it is breathable.

I will thoroughly check the quilt for condensation the morning after using it.

I will get a thermometer/hygrometer to log the weather on my next trip.

Anything i have missed?

Thanks again for all the help, very kind of you all to take the time and go into such detail.

Stu

[Detail Man]

I have been using my weather shield in the same sense, however this brings a good point. I am after a full sock if anyone knows where i can get one in the UK? (the only full 'socks' i can find are actually python skins)

Socks aren't hard to make. It'd be a good project when you get your machine fixed. Does you UQ protector have enough material to wrap it around you, or maybe clothespin it to the ridgeline, maybe on just the windward side? It's not the same as a sock, but it could work in a pinch.

I don't think it is to do with sweat, it didn't feel or smell like sweat when i was wet.

When i say soaked i should clarify my skin was soaking wet, everything else was just moist, including my clothes which where draped on my suspension.

I change into dry base layers and grab a hot meal before bed, so that 'should' rule out me carrying moisture other than respiration into my hammock. I think i do breath into the side of my UQ though, i tend to stuff my face in my bedding.

Sweat is not always perceived even though the body is releasing moisture. It's called insensible perspiration, just like plants let water out of their leaves through transpiration. That your skin was wet tells me you were sleeping without a way for that moisture to escape or evaporate, which could be part of the problem. Environmental and your physical conditions effect how much you insensibly sweat on any given night, hence the variability in your experience.

Having dedicated sleep clothes is a very good thing. Hanging your day clothes on the suspension can a sure way to get them wetter. My practice is to sleep with my day clothes in the hammock between my legs or in the footbox of the TQ. It will help damp (not wet) clothes dry out a bit from your body heat and keep them warmer than if they hung on a ridgeline.

Sleeping with your head buried is a big no-no, at least when hanging. That's a sure fire way to get things wet. I sleep with a balaclava or toboggan depending on the temperature, just so I can keep my mouth and nose exposed to the open air. Still, condensation from my breath will dampen the TQ near my face. Some folks use a frost bib to prevent this in cold weather. Shug has one demonstrated in one of his videos.

Looking at this video i am doing a few things wrong, i have fitted mine as he says not to (RE point of suspension). Furthermore by the description given in the vid i also currently hang it too loose, it also confirms i used to hang it too tight (RE cold spots being located on pressure points or not).

I will try mounting the suspension as per the video/suggestions in this thread and having it set just a little tighter than present to see if that produces any good results.

Glad the vid was helpful. Hangnout is quite a wealth of info.

Other sources of info for you:

It's long, but lots of info on socks and moisture management. MedicineMan's sock is a prototype designed in conjunction with and made by Hangnout.
https://www.hammockforums.net/forum/...ad.php?t=54206

On vapor barrier liners. It will help you gain a better understanding of moisture while you sleep. Billy Bob is a good source of info on this subject.
https://www.hammockforums.net/forum/...ad.php?t=26191

https://www.hammockforums.net/forum/...ead.php?t=6264

FYI a Google search using " site:hammockforums.net vapor barrier liner" is how I found these threads. A very handy Google trick.