Searching for ultralight tarps, I didn't see any that had a reflective side. I thought this would be a wanted feature. Why isn't it? I don't think a reflective coating would add that much weight?
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Searching for ultralight tarps, I didn't see any that had a reflective side. I thought this would be a wanted feature. Why isn't it? I don't think a reflective coating would add that much weight?
If you can figure out a way to apply a reflective coating (which is usually a few atoms of aluminum) to an ultralight fabric, and a way to keep on the fabric, you might have something there.
Some use reflective lines on tent or tarp.
thom
I can see the headline now "hiker air lifted off trail after being blinded by his own tarp". Or forest fire blamed on reflective tarp owner.
Find a white tarp and spare us the glare of a reflective one please. Its bad enough some of us use orange Big Agnes tents.
Asking to satisfy curiosity, not to be argumentative: why would it be a wanted feature?
reflect heat from fire
Actually would make sense on inside of a tent too. Just to reflect back your own radiant heat loss a bit.
That's what I was thinking why you'd want it. But then figured a tarp is usually set too high and not sealed on the bottom, so it wouldn't do anything.Quote:
Originally Posted by HankIV
As for reflecting heat from a fire, why? You shouldn't put something like that which can catch on fire anywhere near a fire. The closer you set up a tent or hammock to a fire, the greater the chance of embers lifting up, landing on said tent or tarp and putting little holes in it.
I only setup my tarp for bad weather and cowboy camp the rest of the time, so it isn't going to be any help. My down bag and bivy sack are where I want my heat retention to be, not the tarp. It tends to be colder after a storm passes through and the clouds are no longer there to trap any heat in, so I would get no benefit from it as the tarp is no longer being used. And if it isn't windy or I have a sheltered campsite, when I do use my tarp, I tend to set it up high and wide to maximize space under it, improve ventilation so I don't get condensation on the underside of the fabric, so it's not going to reflect much heat back at me.
Really to get any benefit of it, you need to be in a narrow short shelter with only a few inches of space between you and the tarp or tent fabric. For those who remember the days before UL tent like shelters became common, you might remember those tiny tunnel bivy like tents which were the only mainstream commercial shelters that allowed you to save a lot of weight. A reflective inner on those likely would have some benefit.
But as others noted, being able to make a long lasting bond with most UL fabrics would be challenging. The stuff on my chrome umbrella (used for desert travel to reduce the sun on the body while hiking) seems to wear off pretty easily as there are black lines all over all the previous chrome umbrellas I've owned where the chrome color stuff has flaked off where umbrella folds or rubs.
On ebay there is a 10x10 silver one side, sorry no link at this time
At this point, as noted above, I think the biggest reason is that the reflective coatings don't last well on the materials that most backpackers want to carry for their shelters. And frankly, as also noted above, the reflection is quite often super annoying.
I have made ultralight tarps out of SOL heat sheets that actually work quite well. I strongly disagree with many of the comments suggesting that there would be little to no significant advantage except in small confined spaces. Reflected heat (IR radiation) is not the same as trapped heat, so it actually works surprisingly well even in an open tarp pitch (think outdoor heaters in restaurants or fruit orchards). That being said, surprisingly well, to me, means noticeably. But, IR reflectivity is at best about 10% of your heat loss. And you can also add 10% more insulation to your other gear to achieve the same thing without obnoxious reflectivity that wears off (or down to 2%) after a couple uses.
As for reflecting fire heat, yeah, they do so obnoxiously well. I generally get too warm too fast regardless of the weather. And, since I need gear to keep warm regardless of having a fire or not, the reflected fire heat becomes a novelty rather than a truly useful feature. And for backpacking, most of us don't build fires very often so their use for that purpose is limited.
So in the end, I disagree with most of the "it doesn't work" comments above. But, just because the reflectivity works, doesn't mean I've found it all that useful, even if it's fun to experiment and play with.
Sometimes it comes down to risk/reward manufacturing decisions. There is risk in developing, testing, marketing, and supporting a reflective surface on a tarp or tent fabrics. In my view, this likely would be a product with mainly a cold weather focus having a limited interest audience as winter approaches and temperatures dip below 40-degrees at night. The market contracts further once there is snow on the ground and most backpackers await the spring season.
There are emergency "space" blankets that are highly reflective, lightweight, and easily carried for use as a reflection fabric to capture heat. These are inexpensive and can be modified for the use the OP has suggested. Given existing reflective fabrics on the market, lack of demand from the backpacking world, and limited cold weather camping market, I doubt if any manufacturer will invest the kind of funding a product like this would demand.
I had ordered one for the same! Does it hold up to rain or non-hurricane winds?Quote:
Originally Posted by nsherry61
Quote:
Originally Posted by nsherry61
I'll have to yield to your experience on this, but I would have thought that any heat trapped or reflected back would not hang around with even the slightest of breezes removing it immediately. Here is a typical tarp setup for me.
Attachment 47808
I was surprised at how well my modified Heatsheet worked as a tarp shelter.Quote:
Originally Posted by mekineer
I used the two person version, so 58" by 98", which, incidentally is close to the same size as my Sea-to-Summit poncho I frequently use as my backpacking shelter.
To test it's durability in wind, I pitched it for two days in my back yard during a storm with "gale force winds", lots of 15-20 mph wind gusting to "over 30", nowhere close to hurricane winds. It held up impressively well. BUT, certainly some of that had to do with how I pitched it.
1) My only modifications to the Heatsheet were the ties-outs made with strips of 1 inch filament strapping tape. These were placed in a way to spread the stress up into the sheets instead of stressing just the edge. I didn't do any edge reinforcements. I just ran the corner tie-out tape strip about 10 inches, or so, up into the sheet material from the corner and the side tie-outs up about 6 inches in from the edge.
2) The other key to success was that all my guy lines had rubber bands on them as shock absorbers so the system gave nicely when hit with strong gusts of wind without overstressing the "fabric".
3) It was pitched like I frequently pitch my poncho as a modified lean-to, not a particularly robust storm pitch. A tarp so small doesn't work in a more enclosed storm pitch for someone 6'4" tall like myself.
Attachment 47805Attachment 47806Attachment 47807
Super simple. Super ultra-light. Super cheap. Super effective. Ah, such superlatives. ;-)
I've carried this a few times as a stupid-light shelter on short trips when I didn't expect any heavy weather and didn't figure I'd really need much shelter. It worked flawlessly the only time I actually deployed it in the field.
I'd encourage you to experiment with your tarp pitch using a Heatsheet(tm) or the like. I think you'll be surprised at how much difference there is in warmth between a clear sheet and a reflective sheet. It's striking. It's kinda like sleeping under the trees vs. out in the open on a clear night. Yes, there is NO trapped heat of significance, BUT the radiant heat, or reflected radiation is independent of air movement, it is energy reflected back from the surface of the reflector to the surface of you, the ground, your bag, or whatever it is reflected back to. It's like the sun shining onto a surface. It still heats and it is not dependent no trapped air to do so.Quote:
Originally Posted by Miner