Stains-Home Inspection, Clarksville, VA

The black stain on a roof is actually an airborne fungus.
This fungus grows and is attracted to certain areas of roofs
that have any of the following characteristics :

Shady roof on north side of house or shady roof under trees
where wind and sun don’t reach.
Any area of moisture or high humidity.

This black fungus is a pesky little thing flying around
in the wind and looking for roof prospects to grow on.
Normally when the airborne fungus shows up on one house in a
neighborhood, it will eventually spread to some of the other houses
in the same neighborhood (as long as the proper growing conditions exist on a particular roof). There are
companies that will remove the stains, e.g. American Roof Brite, if your roof is not very old and the
appearance is intolerable.

For those homeowners who are getting close to replacing their shingles, shingle manufacturers are now
offering FR (fungus resistant) shingles. The FR shingles come in the full range of colors/styles and they only
cost a small fraction higher than normal shingles. The roofing manufacturers have been doing research on
this roof fungus problem and they have changed the granule formulation (top surface of shingle) to include
small particals of copper which the fungus doesn‘t like. I have heard that within the next several years, all
shingles made will automatically be the FR shingles.

The bottom line…the roof fungus problem is just another thing to add to one’s home maintenance list. If you
don’t have roof fungus, consider yourself lucky. If your roof does have it, it’s not the end of the world. Just
clean it yourself or pay someone else to clean it for you. Your roof will be happy that you did, plus you’ll be
happy coming home to a “cleaner” looking house.