Darker exterior color cause higher temps inside?

Mr.Mark wrote:
Obviously dark colors absorb heat and light colors reflect. Everything depends on insulation.

When we were building our current coach I didn't want black so we have dark brown on the upper color and lighter colors below (earthy golds, beige and cranberry). We are well insulated and have four 13,500 btu roof airs.

I usually never need all four. Three units are plenty. Our manufacturer designed the venting on their CAD system as not to have any hard bends in the ducting that would restrict air flow. So, 13,500 btu units will freeze you out and they are lower profile too.

With any coach, you have to watch electrical usage as 50 amp is 50 amp.

Safe travels,
MM.

Unless things have changed over the years, the roof of the Prevost is bright white!

All else being equal, dark colors will result in more heat absorbed.

If there is sufficient insulation and air/con BTU, it can overcome the issue and keep the rig cool.

Our Monaco coach uses styrofoam insulation in the side walls and floor and a combination of styrofoam and fiberglass insulation in the roof.
Since I have not burned my hand with a 1/16" styrofoam coffee cup I have to assume that the 2" of styrofoam insulation in my coach walls means that the few degrees of temperature difference between light or dark colors is negligible.
On coaches with poor insulation, it may make a difference.

Newmar advertises they build thicker than average walls and offer an R-19 polar-pack roof insulation option and I was also wondering how much of a difference they make in keeping inside temps down, even with having a darker colored upper exterior?

Using an infrared thermometer it is amazing how hot the dark colors get on my rv. They will burn your hands in the Summer. It makes a huge difference when we put the awnings out. The frames of the windows are metal and transmit a lot of heat inside too. We have dual pane windows which really helps with the heat and noise.

Back in the '90s, an employee at the Nissan dealer in Augusta, GA, tried an experiment on a nice, hot, sunny southern summer day. He took some test thermometers from the HVAC tech. He placed them in otherwise identical trucks - but one was white and one was black. There was a 40 degree difference in the interior temps between the two trucks.

Rob

Although if you do a lot of fall or cold weather camping, black may be
the way to go! We chose black shingles on our house in Minnesota. More heating here than cooling.
Brian

Dark colors will be hotter than light ones. It is physics. Take the temperature of each color on the side of your coach and you will find that the dark colors are considerably hotter than the light ones. How much the extra heat on the outside of your coach will affect the inside temperature is based on how well your coach is insulated. However, there will always be heat transfer from the skin of the coach to the inside, so a dark coach will be hotter and will require more AC to keep it cool. How much more is a question that cannot be answered without knowing the coach.

When we got our coach repainted, we chose much lighter colors so the coach stays cooler and so the paint lasts longer.

Black is the absence of color therefore it absorbs all wavelengths of light. White is a combination of seven colors of the light spectrum therefore reflecting those wavelengths which leaves it less light energy to convert to heat.

Obviously dark colors absorb heat and light colors reflect. Everything depends on insulation.

When we were building our current coach I didn't want black so we have dark brown on the upper color and lighter colors below (earthy golds, beige and cranberry). We are well insulated and have four 13,500 btu roof airs.

I usually never need all four. Three units are plenty. Our manufacturer designed the venting on their CAD system as not to have any hard bends in the ducting that would restrict air flow. So, 13,500 btu units will freeze you out and they are lower profile too.

With any coach, you have to watch electrical usage as 50 amp is 50 amp.

Safe travels,
MM.