Our roof had algae, moss, and a few lichens... needed cleaning! The Upstate Roof Cleaning was compelling with before/after photos, promising to remove all of the moss, etc from the roof, and great reviews. The team came out in early September - they were on time, courteous, worked well together, and were obviously competent with what they do. They took a long time to rinse the cleaning solution from the roof and nearby plants (so much water that the soils were completely saturated which was a bit concerning).
After cleaning the roof, the algae were gone, but the moss and lichens, while apparently dead, remained on the roof. I asked the team about this and they told me that these areas of dead algae and moss should be washed off in the next 2 weeks by rain and wind. After a month, lichen and moss all remained. I called the company and was told that this could take months so that "Mother Nature" could remove the debris. It is now over 2 months and my roof is not clean. The company was supposed to come (as a favor, they implied) to try to brush or blow the debris off at end of October/early November; rescheduled 3 times and there is now snow.
I have requested a 50% refund as I will need to hire another company to come out to brush off the roof next year. Upstate Roof Cleaning will not provide any refund even in light of their failure to provide the results promised in their advertising. They now deny that their crew could possibly have said that it would take 2 weeks and debris would be gone (but they did tell me this immediately after the cleaning when I saw so much debris remaining on significant sections of the roof in the front of the house).
I believe that their advertising is misleading -- they do not advertise a 2 step process where "Mother Nature" is a required partner in cleaning the moss/lichens off the roof. See the advertisement on this page which does not mention a longer period of time spanning months for dead debris to come off of the roof.
My review -- this company does a good job with algae with a gentle process that includes no scrubbing, brushing or high intensity jets of water. If you have lichens and moss, these may not come off of your roof any time soon after cleaning, if at all. In addition, their custom solution killed leaves on plants in our gardens near the roofline. I lost a lilac, vegetables in a nearby garden, and flower buds/leaves on hydrangea bushes in early September, just as the flowers were blooming. Most of our plants had dead leaves on tops and dying flowers within a week. If you use this company, you will want to cover any and all plants near the house. The company said that plants should be safe under areas of roof with gutters. This was not true in our case as the solution is very toxic to plants. read more