Q - What causes roof stains and why should I worry about removing them?
A - These unsightly stains are caused by airborne spores from black algae (scientifically called Gloeocapsa magma) and mold. This is a living organism that thrives in warm humid climates. Often spread by the wind, much like a dandelion weed, it’s more than just an eye sore. Left alone this growth can cause your shingles to prematurely lose their protective granules and expose the underlying material to the harsh sun and weather. This type of exposure is the main reason why roofs wear out. Also, if you are thinking of selling your home, they could cost you thousands of dollars in lost value. Buyers develop first impressions based on “curb appeal.” How does your house look from the street? Left alone, the algae and mold can spread to other parts of your home potentially causing health issues.

Q - Why is this problem so prevelant now?
A - Roofing materials have changed. Up until about 30 years ago, roofing was typically made by saturating an organic mat with asphalt and then coating it with granules. This mat material was made predominantly with recycled cotton rags. The cotton would eagerly soak up the asphalt producing a good quality, heavyweight shingle. But for several reasons, mostly cost, roofing manufacturers began looking for alternatives. They turned to fiberglass matting for its fireproof and insulating properties. Unfortunately, the fiberglass doesn’t absorb the asphalt as well and as a result the shingles are lighter and more brittle. The manufactures add calcium carbonate (limestone) filler to give the shingles weight. Algae actually feed on this filler material. Not only are the lighter shingles more prone to infestation, they’re also much more susceptible to wind damage.

Q - Why is it worse on the north side of the house?
A - Algae, like all plants, requires 3 things to grow; Moisture, food and sunlight. The north side of the home, as well as shaded areas, doesn’t receive as much direct sunlight as the other sides which allow it to hold moisture longer. Algae require sunlight to grow but only about 1/10th as much as other plants. Too much light and the ultraviolet rays will inhibit growth. The black streaks you see are actually the algae’s way of protecting itself from the UV rays. As the algae mature it develops a hard, black “shell” that blocks the UV rays.

Q - How do I get rid of this mess?
A - The only way to rid your roof of this growth is to kill it. It’s not just a stain that will wash away, it is a living organism. Simply washing it away will only improve the looks for a short period of time. We use a propiertary blend of chemicals that kills the algae and mold and then we just rinse it away gently with water. The residue that is left behind creates a “hostile environment” that keeps the growth from reforming for a longer period of time. Maintaining this hostile environment is the key to controlling the growth.

Q - How quickly will I see results?
A - Immediately!!! Then over the next few months, the roof will actually continue to get cleaner as the chemical residue left behind gets re-constituted every time it rains.

Q - Will it harm my roof to clean it?
A - Not with our process. Our process is non-pressure and we use ingredients that are recommended by ARMA (Asphalt Roofing Manufacturers Association) as well as the largest roofing manufacturer in the country (GAF). And, our process does not affect your warranty.

Q - Will the process harm my plants and landscaping?
A - Absolutely not, if done correctly. We have the expertise and the equipment to insure the safety of your plants and landscaping. That is what separates us from the fly-by-night operators. Much like an exterminator, it takes a qualified professional to handle chemicals in a safe effective manner though our chemicals are much less potent than an exterminator might use.

Q - How long will my roof stay clean?
A - That depends on several factors including the amount of shade on your roof and the condition of neighboring roofs. But typically you won’t see growth forming for several years. We recommend a maintenance treatment every 24-36 months to prevent the growth from returning.

Q - How much does it cost to clean this mess?
A - Typically about 10% of the cost to replace or between $.10 and $.15 per square foot of roof space depending on total footage, roof pitch, height and degree of staining.