I've experimented with two materials I like very, very much, in my Sprinter.

I used 1/2" isocyanurate foam thermal board in my windshield and made HUGE
difference (90%?) in keeping the van cooler.  It's cheap to.

I used black awning material in my windows (limo tinted) and btwn the
cockpit and dining area.  Its like dense nylon window screening.  It allows
me to see outside day or night with limited visibility but enough navigate
when looking at traffic through the slider window.  This material keeps the
AC in the cockpit very well and combined with the tint keeps the police from
seeing me, even with their flashlights.  I stealth full time and have proven
it.  It's very dense so on moderately warm days I'm convinced the van is
cooler than without.  The material comes in other colors, one of which is
white or almond, I believe but I chose black for stealth needs.

I can tell you more if you pmail me.

On Wed, Aug 18, 2010 at 2:29 PM, Bob Stevens <mtbiker62@gmail.com> wrote:

> "Reflective
> is great if OUTSIDE of the Van. We have made prototypes of inside and
> outside thermals and found that inside ones are a waist of time. will
> stop the sun from fading the interior but nothing for heat. If on the
> outside of the Van it will stop the thermal transfer of heat and or
> cold from coming to the inside of the vehicle through the glass."
>
> .... which is why I LUV your front (windshield/driver/psgr windows)
> sun/bug screen. Great for keeping the bugs out, air circulation in,
> and leaving the windshield sun shade down (not rolled up) is very
> effective for blocking thermal transfer there, but even with that
> rolled up, it's still real effective.
>
> Nice seeing you guys near Glacier and glad to see you got home
> OK.
>
> Bob
>

--
Neil2
'82 Diesel Westfalia (USS Tinosa)
'86 Vanagon/Westfalia Wannabe (SaVannah)
'08 170" 2500 Mega Roof Dodge Sprinter (Moby)
Fulltiming since August 2008
Nunquam Pendite Divendium