What do ya'll think about this???

[HighTechRedneck]

I've been watching this thread with interest, and curiosity got the best of me today.  I took my temp gun out to the bus at 4:00 this afternoon and measured the temps on the inside of the windshield and the outside.  With a 93 degree outside actual temp, the windshield measured 138 degrees on the outside surface.  I have the 1/4" foil sandwiched bubble wrap as an inside cover while the bus is parked.  The temperature on the inside surface of the insulation measured 77 degrees with my front Coleman roof air running on low.  I was amazed at the difference that thin Lowe's insulation made!  I checked the temperature on a couple other interior surfaces, and they were within a couple degrees of the insulation temperature.  So---- reflectivity really is an asset for keeping things cool in our buses.   

Since you have the bubble foil and a temp gun, here would be an interesting test to see how sandwiching with other materials affects the performance. Cut two pieces of cardboard the same size (i.e. 2ft x 3ft) and sandwich the bubble foil with no air space between the cardboard and bubble foil on one side of the windshield.  Do this early in the day and have the same AC setting.  When the heat of the day is in full swing and the windshield is getting direct sun, measure each side, the foil only and the foil sandwich.

I have read statements on both side of the issue from people whose knowledge I highly respect.  I think this would be a good way to test the impact of using bubble foil without air space (or glass on the radiant side) surrounding it.

[Nick Badame Refrig/ACC]

Now here's one for ya...

instead of black paint, just bubble foil the whole bus...Lol

Would look like something from Buck Rodgers or something!

Nick-

[orfunauto/Darrell]

OK hitechredneck,
I tried what you mentioned in your reply from yesterday. At about the same time today as yesterday, the outside temp was 95 degrees ambient, the temp on the windshield in front of the cardboard side was at 130 degrees, and the inside temp was 102 on the cardboard.  The outside temp on the windshield in front of the foil was 149 degrees, and the inside temp on the foil was 88 degrees.  Even though I used a thermometer and it was by far not at all scientific, I'm convinced of the benefits of the foil just by the reflected temp of the foil on the outside of the windshield....19 degrees more than the cardboard.....and 12 degrees cooler than the cardboard on the inside.....

[HighTechRedneck]

Just to make sure I'm clear on it, the 102° side with the cardboard, was that with the bubble foil material sandwiched between sheets of cardboard, or just cardboard by itself?

[orfunauto/Darrell]

Just the cardboard.

[HighTechRedneck]

That's what I thought it sounded like.  My curiousity was actually about how effective bubble foil is when it doesn't have air space or glass on the radiant side (i.e. when it is used between rigid foam insulation and the exterior wall/roof of the bus).  Some claim it loses almost all of it's insulating value while others claim it still works well.  I highly respect the experience and knowledge of the people on both sides of the issue so it makes it hard without actually testing the concept.