Attic barrier/ Insulation

[kittyrodriguez]

Several months ago I read a post about someone using a silver attic insulation over their tent. I thought I saved the post, but I cannot for the life of me find it. I tried all the usual searches. Can someone send me in the right direction...

OR has anyone had experience with this product. We are flying for the first time this year, and then taking the BXB. Needlessly to say, our shade options are woefully limited. Normally we have a dome to sit in and a flat topped shade structure over our tent. This year we have a little shade to sit under, but nothing over the tent. Any ideas are welcome. Well, ideas that are light weight and can fit in a checked suitcase...

Definitely panicking more than usual this year. We normally pack our SUV to the gills for our trip, this year we have to condense it into 4 suitcases and two carry-ons...

Luckily, food is already taken care of.

Thanks for any direction/ experience/ advice. And snark, I guess.

[Token]

In theory, radiant barrier should work if you can 100% wrap and black-out the light in the tent.

Practically though,you need 100% black-out plus an air gap and so me kind of venting between the aluminized film and the tent, or you'll still get allot of heat transfer. Just not enough thermal mass in tent canvas.

It will help some but with wind, dust, noise level, etc. might be a slim return on investment/effort.

If your tent poles are on the outside of your tent, might be worth a try as you can use binder clips or tablecloth clips to attach it and have some tension on the film.

[burner von braun]

If we are talking about that silver Reflectix bubble wrap material, bear in mind that it is very lightweight, so it really wants to fly. Extra precaution in keeping it secure might be wise.

You might try searching for 'silver bubble wrap' or 'silver mylar' if you haven't already, though my search results seemed pretty fragmented. I did find one thread where someone was considering using it as an internal radiant barrier and looking to place it all around the inside of his tent. I'm not sure he was ever heard from again.

[Popeye]

Are you looking for this thread?
viewtopic.php?f=277&t=76272&p=1107417&h ... r#p1107417

[trilobyte]

What Token said. The silver material reflects a lot of light and energy, but also becomes very hot and radiates that heat outward in all directions. Without some kind of gaps, covering a tent in that stuff would largely have the effect of camping inside an oven.

[ZigZag]

The stuff NOT to use is that mylar Bubble wrap, especially in your case, the bubble stuff does not really add value and takes up a lot of space.

What you are really talking about is NOT "insulation" but "Radiant Attic Foil" available here: http://www.atticfoil.com/

The stuff reflects 97% of the radiant heat that hits it and it tougher than nails. BUT: It has no grommets. I put a folded strip of 6: nylon strapping tape around the edges and put tarp grabbers (From Am....n) in. It's thin and very light but basically tear proof.

It comes in 5 foot rolls so I had to tape strips together to make the full size tarps. Mine is 25x27

What others are saying about space over your tent is right on. You need at least a foot between the fabric and the tent so air can carry away the surface heat. Just laying it (or a tarp) on the tent does not help and probably will turn the tent into an Easy-Bake-Oven. So you have to think about supports which is why I decided to build a monkey hut.

Full disclosure: I personally have not playa tested this yet, in fact I'm a virgin. But there is an ePlayan named Capinator who has (among others) and this year he is bringing several huts he has built with it. I have talked with him extensively and he knows what he is talking about.

This is Capinators original post
viewtopic.php?f=277&t=76272&p=1107417&h ... r#p1094541

You'll find other posters speaking to this material if you put this into Mister Google
site:Eplaya.burningman.org radiant attic foil.

Hope this helps!

This is my monkey hut:

[Roundabout]

Nice job Zig Zag!! That looks fantastic. I made some flat roof tarps out of this material, except I sewed the seams rather than taping them. I put some 3/16's rope inside the seams around the edges and put grommets just inside the rope. The stuff worked great at a regional - still to be Playa tested this year.

[Ratty]

I love the idea of this. I hope it holds up.

[Krokodyle]

I've joined a different camp this year and, although it's a relatively new camp, Camp Space Hole had a pretty sweet multiple monkey hut design going using attic radiant barrier. They even received a "Home Improvement" Golden Rebar award from long-time burner and photographer Philippe Glade (look near the bottom of him page for interior photos of the huts). The material worked well to block sun and was easy to handle and store.



Seams were attached together using bi-filament tape on the inside and aluminum tape on the outside. Lessons were learned last year (including improving the ground seam) and an improved design will be used this year. Additional grommets and tie-downs as well as an additional "airlock" door panel at both ends to improve temp control and dust. Come on by to 4:45 & E and cool down in our misting tent!

[kittyrodriguez]

Thanks everyone!

Yeah, that was the post I was looking for. I love those giant huts. I wish we had the space for the supplies for a monkey hut...

I do have some old shock corded tent poles from our deceased tent and some of that camo netting we normally throw over the dome. Maybe I can string some of that over the tent for a little relief. I definitely do NOT want to turn the tent into an efficient solar oven wrapped in foil.

How much distance between the shade material and the top of the tent is necessary? Just enough for airflow, or are we talking several feet.

Thanks again for the responses. I am in full panic mode right now. 16 days till we hit the dust.

When we decided to fly, I was so excited to shave those four days off of the trip. And excited about the Burner Express. Seems like it will be fun. But now that panic has set in, I don't understand how people manage to pull this off without a SUV full of supplies! Scariest thing so far is not having bikes. But I am trying to be optimistic and tell myself that it will just force us to explore our own neighborhood, which we never do.

[ZigZag]

The general consensus is that you need at least a foot between the shade and the tent.

[kevinwells]

I am using atticfoil this year as the covering for my Yurt. Here is a photo of the Yurt while i was "fitting" the cover. I used bifiliment tape on the inside and foil tape on the outside. I used 1 inch webbing on the edges, and added grommets. I will report back on performance of the materiel after the burn...
[img]

yurt%20with%20cover%20sm.jpeg

[/img]

[Jackass]

.

[Canoe]

...This year we have a little shade to sit under, but nothing over the tent. Any ideas are welcome. Well, ideas that are light weight and can fit in a checked suitcase...

I'm coming in late, but

For the OP's tent, there's two ways to go:

• have a shade structure, or
• change/modify/add tent materials/structure (i.e., add a radiant barrier...)

The second way is problematic. If you need something to work on the playa, then replicate something that has been proven by playa testing (and preferably by more than one person's claim). The more you vary from a complete method of what worked on the playa, the more you risk getting different results. Using the same materials in a different manner - even if slightly different - is one of those risk areas. For example, some structures with a radiant barrier turn out cool, some are ovens. Some dark monkey huts are cool and comfortable (figure that one out...). Some have had success with radiant barriers and their tents, others have made ovens (with tents: more ovens than success). The properties of the products used do not guarantee your design effort will be successful; keep reminding yourself that "the whole is not equal to the sum of the parts" can go both ways.

Without knowing the size of your tent, for simple playa tested shade structures, start here to see the simple angled tarp and the "flying" wedge (although the rei link no longer works). viewtopic.php?t=70367
There's been a number of variations on the theme. There's a few things you can do "wrong", but that's easily avoidable if you're forewarned and plan, and they're light and easy. You can also ship purchases to your Reno hotel or a Reno UPS Store (search for addresses, days/hours).

[Canoe]

p.s.
Do watch out for camping beside structures with radiant barriers, as they could be reflecting heat on your tent coming in under your shade structure.
Not kidding.
It hasn't happened to me, but if you're in the wrong spot relative to a hexayurt apparently you will not be happy. Some people with hexayurts say they take a spray can of white paint so they can mist a side if they're too close to something and are baking it.

(the monkey huts are good as the curved surface means how much is reflected/concentrated at neighbours is limited, as the sun reflected is dispersed and heat from the ground is largely reflected upwards)

[Canoe]

There's some misconceptions about the properties of the aluminum based radiant barriers. Some properties:

• will reflect ~97% of the light or heat energy,
• will absorb the other 3% as heat.

The first point means that as an exterior surface, they will reflect away:

• the light and heat from the sun,
• the heat radiating at the structure from the sun-heated ground and hot air (surprise! this is why you have heat radiating at you from the North too),
• the light and heat radiating at the structure from nearby structures with reflective or radiant barrier exteriors (really!).

The second point means that over time, the radiant barriers will absorb energy (from the sources listed above) and become hot. Once hot, that heat:

• will conduct to your structure where there is contact,
• will conduct to the air against the radiant barrier, both inside and out,
• will RESIST radiating (inside or out) as the emittance is the same as the absorption (i.e., 3%).

Those numbers only apply when the surface is bright & shiny. Radiance lowers when less shiny, and degrades as the surface is crinkled or covered with dust (we have lots of dust, and usually lots of wind to keep a lot of it blown off - the balance varies). As the reflectance goes down, the absorption goes up and the emittance goes up.

In practical terms, for four common radiant barriers:

• aluminized mylar 'survival blankets' - great at reflecting, but quickly becomes crinkled for increasingly degraded performance (can be as bad as ~60 reflect, ~40 absorb; worse if the aluminum peels off the mylar). The inside surface isn't aluminum nor as shiny and hence radiates much higher. Fragile, so good luck if you're trying to use it under playa winds as an exterior with an air gap.
• survival blanket with plastic tarp backing - more robust, still crinkles but not as bad, mylar can peel off when harassed by the wind, tarp emits/radiates a lot more. Can be good as a shade material if the grommets can stand the wind.
• reflectix (and others) aluminized bubble-wrap - shiny both sides for great reflecting and low emmittance (radiating). Bubble wrap provides some insulation to slow down the heat absorbed by the outside surface conducting to the inside surface, where that inside shiny surface as a low emittance such that while it's hot to the touch (and is heating the air against it) it has minimal heat radiating at things and people inside. Bubble wrap also impedes and limits the crinkling of the shiny surface, but it will degrade some in the wind or with handling.
• rigid foam board sheets - popular for hexayurts - usually have a radiant barrier on both sides, but one side is typically much shinier and should be on the outside to maximize heat reflectance. They've great insulation, resists absorbing heat while what heat over time gets through to the inside surface resists radiating the interior of the structure. The presence of wind also helps take heat away from the outside surface, limiting how concentrated that heat can become, thereby limiting the amount of heat conducting through the insulation.

You cannot prevent the heat from coming in, but you can limit how much can get in during a day by limiting the rate it gains heat; I.E., how long it's comfortable inside once the sun rises. Some structure can remain quite comfortable all day (or cheat with a swamp cooler). With the above list of partial properties, along with the effect of wind crinkling degrading reflectance but removing heat before it can conduct inside and depositing vs. removing playa dust, one starts to see how there are too many variables to allow one to reliably predict what will be effective on the playa.

Your choice as to if you experiment or replicate a playa proven design.

[Canoe]

From looking at the photos provided, I'd guess that in the playa wind the reflectance of the attic barrier products in those wouldn't degrade below 80% reflectance, and likely stay closer to 90% than 80%. When new and in a light wind year, it may even stay above 90%. Note that 80% is still a very desirable level of performance.

I'm hoping that yurt has insulation, as it will stay cooler longer each day. With or without, a DIY swamp cooler is your ace in the hole.

One of the properties of playa structures with shiny radiant interiors, is that any heat inside the structure will reflect back at the occupants (this is handy on cool nights). This includes heat from the occupants and (BIG HINT) heat radiating in a monkey hut's open front/rear, which can turn it into an oven. So if your shiny interior monkey hut is going to have open ends, make sure you've got something to place there to minimize the heat radiating into the interior (direct sun, from sun-baked ground or reflected from nearby reflective structures). It all adds up, and any heat your body (and other's bodies) manages to radiate away gets thrown back at you from a shiny interior.

[Popeye]

+10 for Canoes posts above. There are lots of misconceptions about reflective insulation.
Reflective insulation does not "insulate" as most people think of a down coat as insulating. All it does is reflect infrared. A down coat, fiberglass insulation, etc. slows down the tansmission of heat.
A reflective barrier on the inside of a tent, etc. is not a good idea when you are trying to keep cool.
The air space between the reflective barrier on the outside and the tent should be vented at the top to allow heated air to escape and at the bottom to allow cooler air to enter. This cuts down on conductance gains inside the tent.

[kevinwells]

For me, the sole job of the attic foil is to reflect the daytime sun. Good point about reduction of efficiency due to crinkles and dust, I will keep that in mind.

My yurt cover choice was either a vinyl billboard or attic foil. I decided i had a marginally better chance of coolness with the attic foil.

During the hot daytime, the monkey hut that I visited last year was very comfortable. They DID have a mister going as well. I have a big swamp cooler i am building, so i hope that will be helpful.

As far as insulation, none to speak of. While I know that it would help , Its too bulky/expensive/etc this year. I do have lots of water and power, so I shall squander both to keep cool... nighttimes, it will be no worse than being in a tent.

[Canoe]

kevinwells

> For me, the sole job of the attic foil is to reflect the daytime sun.
That it will, AND all of the heat radiating around too.

> Good point about reduction of efficiency due to crinkles and dust, I will keep that in mind.
If you have the same product as in the photos from the playa, while technically it will degrade from pristine, and enough to be noticeable, it should still be doing a very good job of reflecting heat.

> My yurt cover choice was either a vinyl billboard or attic foil. I decided i had a marginally better chance of coolness with the attic foil.
marginally significantly better chance of coolness with the attic foil

> I have a big swamp cooler i am building, so i hope that will be helpful.
Very much so. Turn it on to instantly start replacing hot dry dusty interior air with cool moist dust-free air.
If sized appropriately, a swamp cooler will provide cool air to cool the people inside structures made with little or no consideration for the heat.
If you stick to a playa tested swamp cooler design (don't substitute without knowing what you are doing, or ask first in Figjam's thread), you should be fine.
Do pay attention to the exhaust venting; and don't leave it open while you're out exploring BRC.

> nighttimes, it will be no worse than being in a tent.
The heat the walls have absorbed will retain that heat for some time (assuming no cooling wind), as it's low emittance will inhibit it radiating away (outside or to the inside).
Touch it to test (careful in the sun), then hold your hand out six inches to check for radiating. For fun, check during the day too: North side vs. South side in the mid-day sun; morning East vs. West (air & ground is cool and not radiating), vs. afternoon East vs. West vs. North (air & ground is hot and radiating now).
At night, where they're exposed, the reflective interior walls will reflect your body's radiated heat back at you. Good if cool; not so much if hot (but you've got a swamp cooler, so you're chill).
(On cool nights, if your structure's for-swamp-cooler exhaust vent is open, you can get convective airflow out that vent, or a blowing wind suck air out the vent, both of which can draw air through a shut-off swamp cooler which may provide some chilling to dry outside air, or it can even blow in through the swamp-cooler)
The shaded playa is cool. Before "everyone" was going for efficiency, swamp coolers or A/C (by generator, solar or mini-wind farms blown by pixies), it was common to have the playa ground inside exposed for its cooling (63F?), with an old cheap thick rug to roll out inside at night to insulate against the chill ground. Will depend on the temperatures that day and that night, as to which configuration will best suit at that time.