How do you create insulation around your tent?

Antranik · Post by **Antranik** » Mon Jun 30, 2008 9:46 pm

So I was reading that one of the good things you can do for your tent is to insulate it from the heat by adding a couple tarps over the tent, with each tarp having air-space over it (so the air acts as the insulator). It's easy to just throw tarps over the tent, but how would you go about creating a good amount of air space in between the tents consistently all throughout the tarp/canvas? Any help would be appreciated.

Also can somebody verify that this is worth the effort? Only because I might not have the ability to create/buy/bring an entire shade structure so this might be something I can do to help keep it cool at least for a few hours more than usual. Aye or nay?

Thanks again.

Dork · Post by **Dork** » Mon Jun 30, 2008 10:08 pm

You don't want to insulate the tent - you want to shield it from the sun. If the tarp is directly on the tent, it will basically aid in capturing heat. If there's a 1 foot or so gap, the tarp will heat up and will be far enough away that it won't radiate much down.

Without shade, your tent will become an oven very early in the morning.

There are ways to create a shade without building something really elaborate - a couple of 2x4's, some rope, and a roof rack on your car can combine for a nice shade. Do some google searches and look through some image galleries for ideas.

Bob · Post by **Bob** » Mon Jun 30, 2008 10:28 pm

Friend of mine reported good results by quilting bubblewrap-type water heater insulation sandwiched between plain old blue tarps.

My theory is you create the coolest spot by shading the ground with opaque material for a couple days so the ground radiates less heat.

YMMV.

Antranik · Post by **Antranik** » Mon Jun 30, 2008 11:32 pm

I see... great... i guess i have to figure out a decent shade structure... at least i got time to do it...

gyre · Post by **gyre** » Tue Jul 01, 2008 1:05 am

Tarps directly on the tent do help.
Insulation is good.
I actually let my tent heat up after about 3 in the afternoon so it's more comfortable at night.
If the sun doesn't hit, it doesn't get that hot.
Spacing is better for the heat, especially with a vent at the top and bottom so you get stack effect.

If you can't do any better a sunblocking tarp stretched out over your tent and spread out will do wonders.

I'm thinking about taking some reflectix this year to use inside the tent.
Silvicool looks good as a tarp.

Hoolie · Post by **Hoolie** » Wed Jul 02, 2008 11:27 am

Here's a guy who used the aforementioned Reflectix to insulate his tent:

http://www.flickr.com/photos/48854860@N ... 68/detail/

ziptie · Post by **ziptie** » Sun Jul 06, 2008 4:51 pm

This is more of an "insulation" question than a "dome" question, so I'm posting it here.

After years of dealing with that horrifying "it's only 0830 and I'm already awake because my tent has become an oven" problem, I decided that this year I'd build a small (4'-radius) dome to provide shade. (Perhaps this is overkill, but I've always wanted to build a dome anyway.)

The problem I'm having now is this: for a dome of this size, where's the line between "lets in too much light and therefore cooks the tent inside anyway" and "doesn't breathe enough and therefore cooks the inside of the dome"? I understand the pros/cons for various materials with larger domes but don't know how that would apply to a little one.

I've been weighing recently among different kinds of camo netting (which I'm planning on layering for better effect)--specifically between the Swedish military snow stuff, which seems popular (but I'm worried about breatheability) & other, more standard US kinds (but I'm worried about them not providing enough shade).

I decided against aluminet as not providing enough shade in this case, and anything too heavy (canvas, tarps) seems definitely out.

Thoughts?

-piper

gyre · Post by **gyre** » Sun Jul 06, 2008 6:05 pm

Block all the infrared and light.
If ventilation will help, the wind will cool the outside just fine.
If heat doesn't get in, you won't need the air.

If you can do this and arrange vented "attic space" over this, then that's just great.
Staggered light-blocking layers can do it.
If you see light through it all, you get heat.

80% Aluminet is available in the us and 100% solid is available elsewhere.
Silvicool may be the same thing.

Ron · Post by **Ron** » Sun Jul 06, 2008 7:29 pm

Airflow is your friend. I'd suspect you'd get better results, and have less work, by staking two big poles down, one in front and one behind your tend. Connect them with rope, drape a shade cloth over that, and stake the hell out of it, all around. As long as you were orientated in the right way in regards to the travel path of the sun I'd bet it would work better than a dome for less effort and cost.

But then again, I'm just not as impressed with domes as everyone else, so there is that. :)

Ron

ziptie · Post by **ziptie** » Sun Jul 06, 2008 9:57 pm

Thanks, guys! I think I'll probably try to go with an opaque system vented at crucial points (also I've been looking into venting and fan systems to help keep air moving without letting light in).

And yeah, it does seem kind of time consuming, but I've been itching to build something anyway. Plus, if it works, it will look like a moon habitation.

-piper

gyre · Post by **gyre** » Mon Jul 07, 2008 4:07 am

The challenge on the playa is keeping ventilation out.
The wind is almost always blowing.
Vent at high and low points and heat will power the ventilation.
Air gaps are more useful on the playa as a radiant barrier, but crucial in the default world for venting heat.
http://en.wikipedia.org/wiki/Stack_effect
http://en.wikipedia.org/wiki/Passive_cooling

A different approach
http://en.wikipedia.org/wiki/Windcatcher

TomServo · Post by **TomServo** » Mon Jul 07, 2008 4:29 am

if you bribe em good, Camparctica may let you camp in one of their trailers

ziptie · Post by **ziptie** » Mon Jul 07, 2008 9:30 am

I suppose I've been underestimating the degree to which air is always moving out there--all I really remember when I think about mornings out there is "hot and still."

Thanks for the input, gyre, and for the links, too!

& nah, TS, if it gets too bad, I'll just find the nearest freezer to crawl into, boots & all. Arctica's too far.

gyre · Post by **gyre** » Mon Jul 07, 2008 9:51 am

If you do need to use outside ventilation, it is important to be sure it is actually cooler outside.
Your body tends to tell you it is cooler outside due to air movement, even when it is quite a bit hotter.
This results in heating up a tent mistakenly.

Entheon offers flash freezing of participants to avoid the heat.

I hope this helps.

ziptie · Post by **ziptie** » Mon Jul 07, 2008 10:38 am

It does help! I think that I'll take these ideas and test 'em out here--it gets pretty hot where I am, & I'll try to fake some wind conditions.

-piper

gyre · Post by **gyre** » Mon Jul 07, 2008 10:55 am

Are you in sf?
Does it ever get hot there?
I thought it just got less cold?
I love the weather there.

gyre · Post by **gyre** » Mon Jul 07, 2008 10:59 am

If you're building a small dome, you might consider a solid panel dome.
That maximizes the strength of the design, unlike the frame with fabric type.

ziptie · Post by **ziptie** » Mon Jul 07, 2008 11:01 am

I've been living in SF for years (other parts of the bay area--like the peninsula--actually do get hot during the summer--in early June it was 103Â° in Palo Alto). I recently relocated for the summer back to where I grew up--the foothills of the Sierra Nevadas. It's supposed to be 100Â° today and boy does it feel like it. I love the weather in SF but I like the fact that I can be outdoors here and go to the river and hike around and things like that. It's a nice summery thing to do.

-piper

ziptie · Post by **ziptie** » Mon Jul 07, 2008 11:04 am

gyre wrote:If you're building a small dome, you might consider a solid panel dome.
That maximizes the strength of the design, unlike the frame with fabric type.

Also: hmm. A friend and I have been furiously tabling design ideas in the past 24 hours, and we'll think about this one. I did look into solid-panel domes a while ago but had forgotten about them 'til now.

Last night we had a wild idea involving aluminum flashing and pop-rivet jack-nuts, but it's looking pricey and we're worried about the aluminum tearing (plus it being blindingly shiny).

-piper

gyre · Post by **gyre** » Mon Jul 07, 2008 11:17 am

6061-T6 aluminum or galvanized steel, esp galvalume, will work.
7000 would be better, but costly.
Plastics too.
Foam sandwich, even with plywood is an old approach.
Wood wrapped in tyvek or silver mylar would last a while.
Cover it in gold mirror to reflect most of the heat.

Many different ways to attach.
There are many captive nut styles.
Through bolting flanges is another way, or sheet metal screws.

If you want to get fancy, Protex makes great stuff.
I like their hose clamps.
http://www.protex-fasteners.com/

Camp Armageddon brings some solid domes out.

Double walled steel ones have been built with a vacuum system for insulation between the walls.

ziptie · Post by **ziptie** » Mon Jul 07, 2008 1:04 pm

It's looking like pretty much any kind of metal plate is out of my price range (tho' flashing is still an option), and I worry about plastic degradation in the sun. Foam is an option.

Yeah, most of this stuff wouldn't be too difficult to attach, given that the inside of the dome is accessible.

And man, that Protex stuff makes me drool. I kind of just want to install latches on everything.

-piper

gyre · Post by **gyre** » Mon Jul 07, 2008 2:26 pm

If you're looking at metal, be sure to price it at the right wholesalers.
Someone in your area can point you to the right place or you can call all of them.
The last aluminum I bought was about $4-6 a pound, I think, for a very high grade finish on german manufactured 6061 eighth inch sheet.
This was after the price jumps.
You may find galvalume scrap or salvage even.
Better chances on plain galvanized.
It is often used for roofing- lots of scrap.

I remember a guy who made his dome from car roofs cut with an ax.

If you can find a copy of Domebook or Domebook II, it may be useful.

http://www.shelter-systems.com/modle.html
http://www.shelter-systems.com/map.html

ziptie · Post by **ziptie** » Mon Jul 07, 2008 2:43 pm

True. I had just been eyeballing it online, which is stupid. After doing the math for some steelyards in our area we realized that by weight it's still price-competitive. The fact that it's less portable than soft paneling is still kind of an issue.

The car-roof dome sounds totally awesome.

gyre · Post by **gyre** » Mon Jul 07, 2008 2:50 pm

It is very important to look for common sizes or in stock pieces.
This may not be easy.
If I had ordered new sheet or more recently stocked sheet or thinner sheet, I would have paid a much higher price.
Every place has some things they are more eager to get rid of.

Find an out of the way shop and you may pay five year old prices.
I know of an old coil of galvalume here bought ten years ago.

jackbird13 · Post by **jackbird13** » Mon Jul 14, 2008 7:10 pm

cut a costco canopy in half and anchor the legs down with ace hardware pier blocks, $2.95 each and use inch and a half lag bolts. Then use a 10x10 tarp. will work great.

edited to remove commercial link

Bob · Post by **Bob** » Mon Jul 14, 2008 9:50 pm

edited to remove commercial link

WTF was that? Do you mind explaining what was removed and why?

Post by **AntiM** » Mon Jul 14, 2008 10:00 pm

Sigh. He sells replacement costco carport covers. I deleted the link to his site where he sells them. I took down other posts which involved selling covers exclusively. I though a brief explanation for the edit would be appropriate. To remove commercial link seemed fairly obvious to me, he had his own commercial link, I removed it.

Why the WTF? This is SOP. A PM would have been nice, thank you. If you'd like to join the commerce vs. fundraisers debate, that's down in policy discussion.

Bob · Post by **Bob** » Mon Jul 14, 2008 10:06 pm

Why not delete the entire post and delete the username instead of leaving it look like you're editing random users' posts? It just looks weird.

Post by **AntiM** » Mon Jul 14, 2008 10:11 pm

I know it looks odd, but if there is any useful info, that can stay. I did outright delete three posts, edited two. The half a canopy idea isn't all bad, selling covers for them, very bad.

I can randomly edit your posts if you'd like. I could make you look crazier than ... well, pick an eplayan.

gyre · Post by **gyre** » Mon Jul 14, 2008 10:11 pm

Bob wrote:Why not delete the entire post and delete the username instead of leaving it look like you're editing random users' posts? It just looks weird.

Death from the skies!
Random terror!

How do you create insulation around your tent?

How do you create insulation around your tent?

tiny domes!