foil bubble pad

[trucker at ez]

I have a stock HH Expidition deluxe. I have slept in it once at 20 degrees F.
with the foil bubble pad under my sleeping bag and was warm. Needed to do some adjusting to stock tarp. Has anybody tried this style of seup or have advice

[FanaticFringer]

Welcome to the site. Wow that's a low temperature for foil bubble wrap. Is this like a car reflector shield or something? Most of us, when not using an underquilt, use closed cell pads.
Most here who own a Hennessy have opted for a bigger tarp than the stock Hennessy tarp. It offers little room for error in bad weather. Also a bigger tarp gives you more room to dress, cook, etc.
A few like the smaller tarp however. If using the stock tarp, it would be best to attach it directly to the trees instead of attaching to the hammock. It will stay taught this way and not sag like it does attached to the hammock.

[trucker at ez]

Thanks for the welcome. the foil pad is for under floor heat so it strong small bubbles with foil on one side whie on other

[trucker at ez]

I have used this pad in tents as a scout leader it worked great. New to hammocks trying what has worked in past. Open for new ideas

[Cannibal]

Question: Does it make that 'crunchy' noise like a space blanket? Or is it stiff enough that it acts more like a pad?

[trucker at ez]

Acts like regular pad. I have been thinking of covering it with a fleece bag then sliding it in my main bag to sleep on it any thoughts

[pure_mahem]

Does this stuff have an official name that you know of? Reflectex was popping in my mind when I read the first part of your post but reflectex is silver mylar on both sides and crunchy so not the same stuff.

[trucker at ez]

dont know of official name but is available at most constuction supply stores.

[trucker at ez]

The roll I bought was 160' long 50" wide. I needed the whole roll

[pure_mahem]

Got any pics of your pad you made?

[trucker at ez]

No pic yet i will get some and post them soon

[trucker at ez]

here is a pic of the foil pad

[trucker at ez]

sorry it is the best i can do I am new to this stuff had to get help

[TiredFeet]

here is a pic of the foil pad

That looks like the Reflectix. Has anybody else tried it for a hammock? If so does it work and how much does it weigh?

I see that Reflectix is available in 4'x25' and 2'x25' rolls.

Ahh - Googling Reflectix, my girlfriend found the tech specs. There are 4 thicknesses: .3", .156", .336" and .156 with the following weights per square foot (oz per square foot): 0.8, .47, .77 and .51.

So if I bought the 2'x25' roll and used a section 6' long, she figures the weights would be 9.6 oz, 5.64 oz, 9.24 oz and 6.12 oz. According to the spec sheet, she says the R-value looks to be pretty good. The only one specified is for the 0.3 thickness and it varies from about 8 to over 14.

It looks like the stuff should work pretty well.

Anybody else tried this stuff in a hammock?

[Youngblood]

Anybody else tried this stuff in a hammock?

Yes, closed cell foam pads work better as pads in hammocks. The specified R-Values for Reflectix are funny numbers. R-Value is a measure of conductive heat transfer and those funny spec R-Values include some combination of radiant heat transfer. Reflectix excels for radiant heat transfer and is not quite as good as closed cell foam pads for conductive heat transfer. For a hammock pad you are dealing with conductive heat transfer and not radiant heat transfer. Bubble wrap by itself can be compared to closed cell foam pads with large air pockets, which compare unfavorably with closed cell foam pads with smaller air pockets. Both Relectix and bubble wrap will work as hammock pads, just not as good as closed cell foam pads. But if the price is right and that is what you want to use, why not, it will work.

[Dutch]

I like to use my truck windshield sunshade in the summer time when CC pad is too much. I assume this would be the same.

[slowhike]

i seems that both sgt rock & the jacks (JRB) have tried the bubble type sheets for hammock insulation too.
and if i'm not mistaken, they determined that there are better alternatives for staying warm.

[dpage]

i bought a $0.99 foil bubble car window screen at my local auto parts store clearence bin. its just the right size for my hammocks and is super warm

[tnhillbilly]

I was at Campers World the other day and they have a roll of stuff that looks just like Reflectix. And there were different sizes gererally about 30" wide and 48"-70" long. I think the price was about $10.00-$12.00 Just passing some info along. tnhillbilly

[psyculman]

I use the "16 wide bubble/foil from HD. ($16) I have slept out down to 18 deg. three times so far. (Hope to get out in colder stuff) I took two pieces of the 16" material, 60" long, taped the pieces together with heavy clear packing tape ONLY at the middle 12" inches of the joint, cut a gentle curve from the that center joint of the two pieces to about 4" from the along untaped joining edge, (center towards outside) and then turned it upside down, and taped the curved edges together. It comes out shaped like a canoe. Next, reinforce the two ends with tape, and, punch a couple of holes to attach 30" of "1/8 elastic cord (scavanged from all my other equiptment) to each side of the pad at each end, so it will pull thru the ends of the HH Expedition, along with the under pad. (like the underpad) Also, I reinforced the two points at the sides where the little loop cords are, (the small loops) for the underpad, and, ran these to also out to attach with the other side loops of the underpad. This goes on TOP of the underpad, but, under the sleeping bag. It will fold in half, and roll up to next to nothing. With a -15 down bag, and my coat under the bag, it all stays put nicely, and is toasty.

[TiredFeet]

So far we have two observations on using these bubble pads.

Some people here have reported using the bubble pads down to some impressive temperatures and find them warm and comfortable.

Meanwhile someone reported that Sgt Rock and the Jack's reported they thought other solutions worked better. Does that mean they didn't work for Sgt Rock and the Jacks??

Is this another one of those subjective reports that means if you are a warm sleeper, they will work and if you are a cold sleeper they won't?

Is Sgt Rock a member here and could he expand on his experience? and could the Jacks expand on their experience other than just "other solutions worked better"? Worked better in what regard? Warmth, sound, comfort, slipperyness, conforming to the hammock/sleeper, what temperatures were tried, etc.

Not asking much :D

But when one or more report experiences that seem to say the bubble pads work pretty well, and others say vaguely they don't, ?????

Youngblood wrote:
Both Relectix and bubble wrap will work as hammock pads, just not as good as closed cell foam pads. But if the price is right and that is what you want to use, why not, it will work.

That seems to take both sides.

I have seen any reports of ccf pads doing better than the 18 F reported by psyculman, but then he seemed to indicate that he could have gone lower. How much lower does one want to go with the ccf pads than the bubble pads can go? If the bubble pads can equal the ccf pads, it would seem the bubble pads are better as far as bulk and weight if the temperatures reached are equal.

[Take-a-knee]

Rock is a member here but he retired from the Army today(?) and starts his thru hike any day. Here is a link, look at item #4. The reflector he used sounds like a different product.

http://hikinghq.net/hammock/hammock3.html#Tip%204

[greggg3]

This discussion is interesting to me from the radiant vs conductive perspective. Youngblood is saying that since you're in contact with the pad, we should worry about conductive not radiant heat transfer which makes sense, yet in my experience with the HH supershelter I found a dramatic improvement in warmth when I added the space blanket as T. Hennessey recommended. It suprised me a lot that a thin space blanket could make that much difference (actually the whole SS itself surprised me at how warm it was for its thickness, I just found it to restrict the spread/width of the UL explorer and make it less comfortable). It makes me think that it has to be doing something and makes me question: are we sure that the radiant heat component is negligible in the hammock arrangement?

[greggg3]

Still thinking: wouldn't the ideal situation for a space blanket be if there were someway to hold it a fixed distance from the skin with a vacuum in between, so there would be no conductive heat transfer and a large portion of the radiant heat would be reflected back to the skin? Sort of like a thermos bottle. In this arrangement the reflective surface would be very important, right?

Since holding the space blanket off the skin with a vacuum in between is impractical if not impossible, if we continue the thought experiment, we might put different things in between the skin and the space blanket - say it was held off the skin by a bunch of toothpics in a grid spaced out every inch or so to hold the space blanket away from the skin with air filling the gap in between. (I know not very comfortable!) The air and toothpics can carry away some heat from conduction/convection but the space blanket will still be providing a lot of service reflecting radiant heat. Now say I put bubble wrap between the skin and the space blanket, less than the ideal situation but wouldn't the space blanket be reflecting some radiant heat (while the enclosed bubbles are reducing convection losses and the plastic, being a poor heat conductor, is reducing conduction losses?

I think I've talked myself into some field (backyard) trials with reflectix. To those that have used it - how well does it hold up? and it sounds like it might be a little heavy for its thickness?

[greggg3]

Hey, why couldn't I just put the space blanket under my regular ccf pad? Wouldn't that be almost the same as reflectix? Or should it go on top of the pad ? :confused: now I've confused myself, I think I've thought too much too early in the morning - I hate it when that happens

[psyculman]

I have a few additional bubble pad notes:
1. I am a warm sleeper
2. Sleeping bags make a big difference here
3. My HH hexifly (very large) covers down to the ground, there is little breeze under the hammock

My Eureka Eaglepoint -15 (synthetic) is sufficient to 18 deg. with bubble pad. ( bulky, and not packable, takes up too much room)
My Kelty Zephyr -15 (down) needs a parka under my hips, the down compress' there, and it's a cold spot.

I haven't used a space blanket with colder conditions, but will try it. Have not been able to go out on colder nights yet. Hammock inside temperatures have never gone below 35 deg. Condensation, although there, has never been a problem, both on the over cover, and in the under opencell pad.

[Youngblood]

This discussion is interesting to me from the radiant vs conductive perspective. Youngblood is saying that since you're in contact with the pad, we should worry about conductive not radiant heat transfer which makes sense, yet in my experience with the HH supershelter I found a dramatic improvement in warmth when I added the space blanket as T. Hennessey recommended. It suprised me a lot that a thin space blanket could make that much difference (actually the whole SS itself surprised me at how warm it was for its thickness, I just found it to restrict the spread/width of the UL explorer and make it less comfortable). It makes me think that it has to be doing something and makes me question: are we sure that the radiant heat component is negligible in the hammock arrangement?
Gregg,

Your space blanket is also a vapor barrier. A closed cell foam pad is a vapor barrier but an open cell foam pad is not. Plastic drop clothes and trash bags are also vapor barriers. You might get the same effect using a sheet of plastic as your space blanket when you put them between the bottom side of the hammock and an open cell foam pad that is held against the bottom side of the hammock?

[TiredFeet]

This discussion is interesting to me from the radiant vs conductive perspective. Youngblood is saying that since you're in contact with the pad, we should worry about conductive not radiant heat transfer which makes sense, yet in my experience with the HH supershelter I found a dramatic improvement in warmth when I added the space blanket as T. Hennessey recommended. It suprised me a lot that a thin space blanket could make that much difference (actually the whole SS itself surprised me at how warm it was for its thickness, I just found it to restrict the spread/width of the UL explorer and make it less comfortable). It makes me think that it has to be doing something and makes me question: are we sure that the radiant heat component is negligible in the hammock arrangement?

Talked to my engineer girlfriend about this. She found it interesting. Her explanation is that you radiate heat all the time. Even when you are in contact with the pads, quilts etc. You radiate heat. With no contact, the conductive loss is then limited to the loss to the surrounding air or goes to zero for a vacuum. But you always have the radiant heat loss. That's why they silver the interior surfaces of glass vacuum bottles - the vacuum cuts the conductive heat loss to almost zero and then the silvering cuts the radiant heat loss also.

It's just that when you are in contact with another material, then the conductive heat loss will usually be greater than the radiant heat loss. By adding the space blanket in addition to the pads (open or closed cell) you are also cutting the radiant heat loss by reflecting it back to the body. Just like silvering the interior surfaces of that glass vacuum bottle. Without the space blanket you still have the radiant heat loss, it is just absorbed by the pad or quilt or whatever and then conducted from there away from the body.

I think she explained it far better since she understands it better.

[greggg3]

Gregg,

Your space blanket is also a vapor barrier. A closed cell foam pad is a vapor barrier but an open cell foam pad is not. Plastic drop clothes and trash bags are also vapor barriers. You might get the same effect using a sheet of plastic as your space blanket when you put them between the bottom side of the hammock and an open cell foam pad that is held against the bottom side of the hammock?

Hmmm...that is a possibility I hadn't thought of. But this vapor barrier is down below the bottom of the hammock...but you're right with the super shelter it's all held up pretty tight. I guess I need to try the same arrangement with a sheet of plastic and compare to the space blanket.

[Hector]

I think psyculman's -10F synthetic bag is so noncompressible that it acts as pretty good bottom insulation on its own -- good to +18F, actually. I once had a -5F synthetic bag you could sleep in to +15F on the bare ground, no pad, with ease (you just couldn't fit it in a small pack :-). I think he'd need to test the bag alone vs. the bag with pad to figure out how much the pad actually helped.

[warbonnetguy]

I think psyculman's -10F synthetic bag is so noncompressible that it acts as pretty good bottom insulation on its own -- good to +18F, actually. I once had a -5F synthetic bag you could sleep in to +15F on the bare ground, no pad, with ease (you just couldn't fit it in a small pack :-). I think he'd need to test the bag alone vs. the bag with pad to figure out how much the pad actually helped.

good point, i've used the older/cheaper syn bags in hammocks before, and the uncompressible fill does insulate under you. works great for car camping in milder weather.

everything i have read says that any reflective material is most effective with air space between the material and whatever it is insulating. the ocf of the ss may create this somewhat. not sure if ccf would do the same, but it seems like it would be most effective when suspended outside the hammock, laying directly on it will eliminate any air space. suspend it from the outside, and you may be able to create some air space. you would want it loose fitting with a tight seal around the edges.

[TiredFeet]

everything i have read says that any reflective material is most effective with air space between the material and whatever it is insulating.

Asked my engineer friend about that.

Her reply: "Depends on where you read it and who wrote the information and the context of what they were writing about. But a reflective material reflects whether there is contact or no contact. A reflective surface does not depend on an air gap in order to reflect electromagnetic energy (light and radiative heat or infrared energy)."

So maybe it depends on what it meant by "most effective". But as far as reflecting the radiative heat energy, an air gap adds no value.

Maybe the writers were concerned about condensation on something such as a space blanket?? In that case an air gap would be of some value, but not much if the air gap is small enough to stop air circulation and thus limit conduction and convective heat loss.

[warbonnetguy]

interesting, when i read it it was talking about construction uses.

[Law Dawg (ret)]

Uses this type of pad, Radiant reflective bubble pad, and no mention of anything else. I wonder about how it works with the Snake Skins for take down and what insulating protection it offers. Obviously Tom & co think it works well enough to offer it.

PS, newb here doing my homework as titanium knees now make much of the groung camping I have always enjoyed very difficult. I am thinking about a HH Explorer Delux A-sym (zippered) with a Supershelter to experiment on insulating. Some type of radiant reflective bubble pad sounds like an option over the krinkly (is that a word?) space blanket in addition to the foam pad the SS comes with. Weight is not a huge factor as I will be using it motorcycle camping.

Thanks for your site y'all, good spot to sort it out.

[jtbradyl]

I have a "Deep Jungle" XL and the reflective pad is rolled up separately. And it is rolled up top to bottom. Although, I also have a "Deep Jungle" regular pad and it has been folded over at the sides and then rolled up. Probably could do the same with the XL pad except that it came stored in a nice long mesh bag so I use that. The reflective pad is quite bulky so i don't see it being rolled up with the hammock and tarp and the snakeskins fitting over. I've been thinking about using a 3/8 in. Volara CC pad (4 lbs. density) That might roll up with the hammock and fit in the snakeskins. Or maybe the maybe for a tighter roll using 2 lb density Volara if it's not too fragile.