The Roof Cleaning Institute Of America Training & Certification Forum
"Find A Certified Roof Cleaner Directory"

It just crossed my mind and got me wondering?

I use all of the sites below:

{GAF Roofing Manufacturer}
http://georgoulisroofing.com/wp-content/uploads/2012/01/Algae_Staining_on_Shingled_Roof_Surfaces_-_Steep_Slope_Techn-43-808-v3.pdf

{ARMA Roofing Manufacturer Association  Cleaning Bulletin}
http://www.asphaltroofing.org/algae-discoloration-roofs


{CORNING Roofing Manufacturer} Click number 1 "algae growth"
http://roofingca.owenscorning.com/homeowner/thingsyoushouldknow/needaroof.aspx


The ARMA also says not to allow anyone to apply any roof coatings. This is a common sales gimmick. Usually pressure washing companies-not roof cleaning companies-will pressure wash your roof and then sell you an after coating, which they want to reapply every 2 years. Names like Roof-A-This or That. Not wanting to name any specific one. Read the ARMA warning below.

http://www.asphaltroofing.org/coating-asphalt-shingles-after-installation