Roof cleaning..
 

Is it necessary? If so, how is that determined?

thanks

If your roof is showing signs of mold, then a cleaning might be warranted. If your house is less than 10 years old, I would call home warranty first to see if there are other options. In any case any cleaning should be LOW pressure and with appropriate cleaning agents by a licensed firm. Ours is almost 9 years old and shows no signs of needing to be cleaned.

Like so many things it is a matter of opinion. Roof shingles are tar with fine gravel on top.
The color is the color of the gravel. The gravel protects the tar underneath that people call roofing shingles. Washing the roof will remove some of the gravel. What people see is dirt is partly dirt and partly mold. As it is black, in color a light colored roof will show the dirt and mold more.

Our roof is dark colored. It is ten years old. There is some mold on it. If, I was selling, I would likely have it washed. Since, I am not selling I would not have it washed.

aesthetics

Only if under bunch of oak trees. My roof approaching 20 years old and no mold or dirt. No oak trees close.

I’ve been in Florida a long time , I have read some articles and talked to some roofers and the consensus has been don’t clean the roof

Certainteed , the prevalent mfg of Villages roofs, will inspect, and if the mold showing is a mfg. defect, they will clean and treat with a 10 year warranty. They will also pressure wash your house at a discount if you have it done same day.

Someone on my street had their roof soft washed. The roof looked great after washing. The chemicals used to wash the roof messed up the painted driveway. The driveway had to be totally redone.

I expect there is details missing. Any chemical strong enough to damage a painted drive would surely kill plants and damage paint on the home itself. I would expect the people who power washed the roof also power washed the drive. For the roof they would use low pressure. At high pressure you can actually strip paint off with a power washer.