Everyone agrees that roof stains are ugly, but is this a destructive problem? You bet it is! Hundreds of field tests confirm it. If you're still not sure, try a simple test.

There are several ways to test a shingle roof for granule loss. Many home inspectors perform them. The two easiest are explained below:  

Method #1 is a visual inspection of the gutters. Where ugly streaks or stains are present, excessive lost granules accumulate in the bottom of the gutter. In some cases, the entire bottom of the gutter is covered! Now, inspect the gutters where no roof stains are apparent. There are very few granules to be found here. Seeing is believing. Why? Protective granules are being lost as roof stains get worse. Permanent damage can result to any roof in less than 7 years! Most importantly, shingle manufacturers consider this destructive problem a condition of the environment, and not a defect of the shingle. Therefore, the warranty does not cover this type of damage. The homeowner is on their own. Unless you just enjoy buying a new roof on occasion, treat it with Roof Reviver(TM) Roof Cleaner.   

Method #2 is called a "Pick Test". Used by shingle manufactures to calculate "adhesion percentage", it simply shows how many protective granules stuck to the shingle, and how many fell off during manufacturing. Take a flat object, such as a block of wood and wrap tape around it so the sticky part is facing outward. Now press it firmly against the shingles where stains are present. Take several samples to get a good collection of data. Now, repeat the test where no stains are present. When finished, the difference in the samples should be visibly apparent. If not, you can pains-takingly count the lost granules and log the results.

You guessed it. Samples taken from the stained areas contain far more lost granules than the non- stained samples. One of these simple tests will prove that the ugly streaks and stains are destroying your roof. Once the protective granules are lost, the roof is ruined. Here's the good news: If caught in time roof damage is very easy to prevent. Roof Reviver(TM) stops the progression of roof stains!

The photo above shows a gutter loaded with lost granules on the north side of the house. (roof stains prefer the north side) Incredibly, the south side of this 10 year old building had no roof problems, and zero granule loss! Further proof that roof streaks destroy shingles. If left untreated, your roof might be headed for an early retirement!