Black Stains on Roof

We are a nationally recognized Roof Cleaning Training Company, teachers of the very latest advances in safe, non pressure roof cleaning methods.


Your local Tampa Roofing Contractor knows why your asphalt shingle or barrel tile roof is discolored, and so do we!

The Black Streaks you see on your cement tile or asphalt shingle roof isn’t actually dirt at all.

Your asphalt shingle or cement tile roofing is discolored, streaked, and in need of roof cleaning w/o pressure washing, because Black Algae is growing on it.

This plant(Gloeocapsa Magma) thrives in the humid climate here in the Central Florida area.

It feeds on the limestone filler now being used in your roof shingles.

Gloeocapsa magma is a species of cyanobacteria.

Cyanobacteria are an ancient line of photosynthesizing bacteria, which photolyze water generating oxygen gas.

Ancient cyanobacteria were ancestral to the chloroplasts of all plants on earth.

Gloeocapsa magma has gained notoriety in Florida, and is spreading rapidly throughout the USA.

This particular type of cyanobacteria is responsible for creating black stains and streaks on roofs in Tampa.

The bacteria accumulate over time as it feeds on moisture and calcium carbonate filler.

This accumulation begins to show the black stains as the cyanobacteria develop their dark and hard UV-protective outer coating.

The main reasons for the rapid spread and noticeability of these cyanobacteria in Tampa are thought to be:

1. Rising humidity, rainfall, and warm temperatures in Tampa, combined with more and more airborne bacteria spores, promotes their spread with these favorable conditions.

2. Fiberglass shingles (the most commonly seen amongst today’s residential homes in Tampa) are made with limestone as a filler (in the asphalt).

These roofing shingles hold moisture and organic “bacteria food” material longer (especially on the North facing side of the roof) than the paper/asphalt/ceramic shingles common 20+ years ago.

Additionally, these particular black algae enjoy the limestone as a food source.

Once the bacteria have become noticeable, the black roof stains will continue to worsen year to year.

There is debate over the actual harmfulness of this particular bacteria to roofs in Tampa, as there is little supportive scientific research.

However, most “experts” within the subject area conclude the bacteria to be harmful, if left untreated, as the black algae growth holds moisture within the roofing shingles causing premature aging, rotting, and/or granule loss.

If nothing else, this roof plant will spread when it rains, causing black stains and mildew to appear on concrete driveways, sidewalks, and pool decks, as well as on the walls your home.

In years past, this Gloeocapsa Magma plant simply didn’t have a food source.

Therefore, roof cleaning was seldom necessary.

This all changed with the introduction of fiberglass roofing shingles during the past 20 years.

The fiberglass roofing shingles made today contain massive amounts of alkaline food that this roof algae just loves to feed on!

That food of course, being the limestone filler currently being used by shingle roofing manufacturers.

Because the Black Algae on your roof is now being “fed” by this filler, the newer, “limestone enhanced” roofing shingles, get “dirty” even faster!

Therefore, cleaning roofs w/o pressure washing them more often then the asphalt roofing shingles of the past is required.

It is not the fault of improper roof installation, or incorrect shingle selection by your Tampa Roofing Contractor.

Sort of like a lawn being fertilized, this Black Algae is feeding on your roof, and spreading like a weed throughout your property!

Owens Corning, the worlds largest asphalt shingle manufacturer, and many Tampa Roofing Contractors, feel that this Algae can cause premature granule loss w/o periodic non pressure roof cleaning, and considerably shorten the life of your residential or commercial Tampa Florida roof!

As your lighter colored asphalt or fiberglass roofing shingles are turned black by the accelerated growth of the Algae, they becomes less reflective, and retain more heat.

This makes your air conditioner work harder to overcome the increased heat load, costing you money and increased discomfort.

Roof Algae spreads itself by unseen, microscopic airborne spores, just like a dandelion weed. It is also spread by Birds, and other “roof visiting critters”, as they go from house to house.

Your black roof algae infestation can and will easily spread to your neighbors home if roof cleaning w/o pressure washing is not performed.

As you can now see, dirty shingle or barrel tile roofing is not just an eyesore, or something for your Tampa Homeowners Association, or Property Manager to complain about.

It can and will compromise the efforts of your fellow homeowners to keep their own asphalt shingle or barrel tile roofs clean!

That’s one reason many Tampa Homeowners Associations and Property Managers send out letters requiring non pressure roof cleaning.

Apple Roof Cleaning Tampa feels the bottom line is this.

Allowing your commercial or residential shingle or barrel tile roof to remain dirty, can and will compromise the roof cleaning efforts of fellow homeowners and other commercial establishments in your immediate area!

Your reasons for wanting roof cleaning are your own.

Whether you are selling your house, getting ready to paint, had some asphalt or fiberglass roofing shingles or tiles replaced, got a nasty letter from the Tampa Homeowners Association or your Property Manager, or just take pride in your home, please remember one thing.

All residential and commercial roof cleaning in Tampa is not the same!

Many Tampa Roofing Contractors can tell you of compromised shingle roofs, or even barrel tile roofing they have prematurely replaced, due to improper roof cleaning methods like pressure washing.

Read the article below from a St. Petersburg FL newspaper, and see what happened to some unsuspecting consumers who hired the wrong Tampa Roof Cleaning Company.

” TAMPA – A container with an acid chemical residue exploded Friday morning in New Tampa, severely burning a 36-year-old man. Investigators say Kenneth Toledo, a man who owns a Tampa Pressure Washing Business, poured chlorine and water into the container, which had previously been used to apply an acid chemical wash.

The container had not been properly rinsed after pressure washing use, and the resulting roof cleaning chemical reaction caused the explosion, officials said.

The container exploded as Toledo scaled a ladder to chemically clean the barrel tile roof of a Hunter’s Green home in the 17800 block of Osprey Point Place in New Tampa, pelting the Tampa Pressure Washing Business owner with roof cleaning chemicals, and shrapnel.

He was airlifted to Tampa General Hospital.

His condition was unknown Friday.

The explosion also blew a 2-foot-wide hole in the homeowners barrel tile roof.

Roofing Tile was scattered about the driveway. Tampa Roof Cleaning Explosion Link

Just because it’s supposedly “Non Pressure Roof Cleaning” doesn’t automatically mean it is SAFE!

Some non pressure methods of cleaning your commercial or residential roof chemically can actually be much WORSE than even harmful pressure washing! Roof Cleaner Recall Link

Call Apple Roof Cleaning Tampa today at 813 655 – 8777 for a free roof cleaning estimate by telephone.

Our Tampa Roofing Contractor and Homeowners Association references will be gladly furnished upon request.