by Kathy Maynard, reprinted courtesy of ServiceMagic.com

Q: I have a 12 year old white asphalt shingle roof with a lot of dark staining from the leaves of the nearby oak trees. Is there anything I can do about it?
A: Your question about discoloration on your roof is a good one that we hear a lot.
There is no recommended solution for "oak" stains. However, according to the MSA (Master Shingle Applicator) manual published by Certainteed Roofing Products, the following is suggested for fungus or algae and should lighten oak leaf discolorations.
The effectiveness of the cleaning and bleaching techniques is temporary, and discoloration is likely to recur.
CAUTION: High-pressure washing systems for algae removal should be used only by reliable professionals because incorrect application can result in removing granules and shortening the life of the roofing system.
This information is brought to you by Will and Kathy Babin of Superior Roofing in San Antonio, TX.
If you don't have the proper ladders or walk boards and/or decide it is too risky to climb on your roof, you may return to our site at: http://www.servicemagic.com, type "Find a Roof Cleaning Service" into the search box and submit a service request so we can match you with the ideal service professionals in your area.
Kathy Maynard
-- Tips courtesy of Service Magic