[T2] color of tarps

[jon]

In my extensive experience playing with tarps in the playa desert sun, 
*_only_* the silver tarps are acceptable as shade structures.  
www.canopymasters.com are who I purchase mine from; excellent service 
and the fittings + ball bungees make putting together a**_durable_ shade 
structure a snap. ALL other tarps let through some part of the 
spectrum.  White seem to be the worst.  I have to wear sunglasses inside 
a white tarp shelter during the day: my eyes are watering and extremely 
painful without them. Opaque surfaces, i.e. metal, coated with pure 
white paint are superior reflectors to those painted silver, however 
white tarps are neither opaque nor pure white.

Our experience has also shown that a second layer, spaced 6 inches down 
inside, nets an additional 10 degrees temp drop.  All tarps re-radiate 
heat inside, they are tarps not insulators.  The second, inside, tarp 
only has to deal with IR spectrum energy, not the full spectrum the 
outside one does.

For cool in the sun try a polyiso  hexayurt.  http://hexayurt.com/ There 
are fold flat designs on that page.

YMMV. jon