Originally Posted by steelheadbluesman
Can't see it ------ So why wash it?
I do realize you put the smile at the end but I will answer your question anyway.
A WHITE roof reflects the summer sun better making less work for your air conditioners. It also does not radiate heat as fast in winter, making less work for your wallet at the propane station.
Second: A clean roof lets air slide over it easier making less work for your wallet at the fuel pump.
Third: Part of the cleaning process is an inspection, this is where you catch the leak before it becomes a problem and add DICOR caulk to the hole to seal it.
Forth: Though a rolling stone gathers no moss, you roof should never roll, it is supposed to be up on top all the time, if it rolls over, you don't need to worry about it any more cause you have much bigger problems (And yes this is a "Serious joke" True, but worded to be funny, I hope). Thus the roof DOES gather moss, and if you let it grow, let it grow, let it grow, It pokes thousands of little holes in your very expensive roof.
Had to order a new part for my RV from my service tech the other day.. Met her in the storage lot at the campground, where she is replacing the roof on a camper where just that happened. Many expensive hours of labor, plus materials as she tore it off all the way to, and including, the plywood, She was cutting and fitting new plywood when I was there, Then she will have to re-do the cealing as well.. Glad I'm not paying for that repair.