Bus Roof Coating

[TrevorH]

If you dont have any leaks that need to be repaired, I would leave it alone.  If at best you gained a couple degrees you are adding something that needs maintained.  Your bus looks great as it is, I wouldnt touch it!

[gus]

Nothing reflects sunlight as well as a good white glossy surface. Nothing! This goes double for anything silver, a popular myth. I just shake my head when i see people coating the tops of mobile homes with silver.

You can test this by laying some different colored metal panels in the sun for an hour or so.

Lay your hand on the white first, but be very careful about laying your hand on darker colors or silver. You can very easily see the difference, it is no contest.

My 4104 is covered with white vinyl. It has been trouble free since '95 but has one fault, it has a grainy texture which traps dirt. It is a pain to clean but does look good when clean. The naysayers have said it won't hold but it is still there as good as new.

I don't recommend vinyl because it has to be applied perfectly and I think a good thick tough white coat of some sort is better in the long run as long as it is smooth.

[Sojourner]

ghanson...Since you already have the Saudi roof which is much better isolation to sun heat then anything else. Providing that all tunnel passages is clear of spider's web and debris. So that air will flow while bus is in stand still as well traveling. Saudi roof greatest effectiveness is when the bus in stand still.

IR gun test will tell you that white is the coolest of all colors.

About sealant paint....only if you have a leak.

Otherwise use the good whitest paint and spray UV protect clear coat over it...it make more resistant to tree brushing or scratches as well keeping it clean and last longer.

About color offset appearance from viewing at ground level. On a bright sunny day, you have a hard time to see it being white roof as long the side skin's color to it's roof edge is 18% gray (photographic neutral) or lighter. Even if the darker color skin of your choice, you may still be satisfy.

FWIW

Sojourn for Christ, Jerry
PS...wish my bus has your Saudi roof.

[WEC4104]

Nothing reflects sunlight as well as a good white glossy surface. Nothing! This goes double for anything silver...

Pardon me for nit-picking a technicality, but a silver mirror-like surface DOES reflect sunlight better that white. However, it is not the light reflectivity that matters, it is what happens with the heat absorbtion and dissipation that makes white the best color.  I completely agree that white does the superior job compared to silver coatings.

[Lin]

By the way, I just wanted to mention also that when coating the roof with these products, I also coated the AC cowlings to help protect them from UV deterioration.

[gus]

WEC,

You are correct, but there is no way to get that finish on a bus top. If that weren't true mirrors would be white??

I'm sure you know the silver I mentioned turns a dark gray in a short time and becomes a much worsel heat sink than when new - which is bad enough.

And, as you said, the heat absorbed by a mirror is considerable, much more than white.