making decisions about roof replacements

making decisions about roof replacements

Roof Discolored? Know 3 Potential Reasons Why

by Lorraine Fisher

Nobody wants a roof that is a community eyesore with discoloration. Unfortunately, there may be multiple factors at play that are causing this blemish. To fix the problem, you must know what is causing it to occur. Here are 3 reasons why discoloration can happen to a roof.

Pigment From Asphalt Shingles

There is a process called extractive bleeding where black pigments found in your roof's shingles can cause a stain to appear. It typically happens when the shingles start to lose the black pigment in them, causing streaks after a rainfall. Pigment is added to the mix of asphalt, and streaks occur due to a defect in the asphalt.

You can narrow down the problem to the pigment if you see the problem originating from specific shingles on the roof. Unfortunately, this can happen to your shingles regardless of factors like sun exposure and orientation. The best way to prevent it is by purchasing shingles that are high quality.


Are there black stains that appear only on parts of your roof that have shade? This could be algae growth. Since algae grows with the help of moisture, places that have shade from nearby trees or other buildings will prevent sections of your roof from quickly drying. The discoloration from algae will have a uniform look, which is quite different from than the discoloration caused by the pigment.

For algae stains, contact a local roofing contractor to take care of it for you. It requires some powerful chemicals to remove the stains, and a professional can avoid causing damage to your roof during the cleaning process. They can also install a metal roof cap made from zinc or copper, which will deposit tiny amounts of metal across the roof when it rains, which kills algae.


Rust, or oxidized metal, can be brown or red. It only will affect metal roofing material and parts of the roof that are metal, such as the flashing. The rust can wash off the flashing and easily discolor the roofing material beneath it when it rains.

Metal that has rusted will become weak, potentially having a hole in it. Avoid walking on any part of a metal roof that has rusted, and have the spot professionally repaired. It will involve patching the spot and painting over it so that the repair is seamless.

Can't seem to determine the cause of the discoloration? A roofing contractor can assist with that as well.


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making decisions about roof replacements

Is the roof on your home ready for replacement? If so, do you know what type of roofing you are going to have installed to replace it? Will you have the existing roof removed, or just have the home re-roofed? You will face several decisions while you work to replace the roof on your home. Scroll through my site to find a great list that can help you decide what product and method of installation will be best for your home. Hopefully, the information provided will take some of the confusion and stress out of this big, important home improvement project.