I have been experimenting with this for several years. Using an infrared
thermometer, I first tested colors to see what reflected heat the best. By
far it is white. I would have guessed silver to be the same or better, but
not at all. Next I wanted to add some sort of reflective agent to the paint
to increase it's ability to "Bounce" heat away.
http://www.hytechsales.com/insulating_paint_additives.html
This worked extremely well. Next I removed the half torn head liner (this is
on an 82 sunroof turbo diesel) And on the recommendation of the local
hardware expert, I glued directly to the inside roof an insulation material
that was foil-like on the outside and sandwiched a fiber insulation in the
middle. http://www.steelbuilding.com/buildings/accessories_foil.htm  Very
inexpensive, and I am thrilled with the results. I live in the high desert
just outside of LA, and instead of AC I have a 1600 watt voltage inverter
powering a 30" portable swamp cooler. This has all worked well for over
25000 miles. Hope some of this can help you.

----- Original Message -----
From: "Kenneth Wilford" <kenwilfy@COMCAST.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, June 27, 2007 5:57 PM
Subject: Re: Reflective tinting ...

> What I would like to know is if anyone has tried putting something
> reflective on the roof of the van and if so did it help?  I have been
> thinking about trying to put either aluminum tape on the roof of my van or
> maybe something like the "b-quiet" material.  My idea is that this should
> reflect most of the heat that the dark paint of my vans is now absorbing.
> I have two Carat Vanagons that we use.  One is maroon and the other is
> dark blue so both get really hot when they sit in the sun all day.  I try
> to park them in the shade when I can but this is not possible at my house
> where the PO of the house was a nut that cut down every tree in the yard
> and even some on the property next to his just for good measure :-)  So
> has anyone tried this and if so, what was the result?  I may try it, I
> keep thinking about doing it every year, but then I have to do before
> tests and after tests and write it up for the list and take pictures and
> all of this during the busiest time of the year for me.
> Not as simple and just doing it and see what happens :-)
>
> Ken Wilford
> John 3:16
> www.vanagain.com
>