Your roof has a big impact on the overall curb appeal of your home. It’s easy to take a great looking roof for granted. Discoloration and stains on your roof are not only unsightly, but could be signs of a larger problem with your roof.

We want to make the roof repair and replacement process as transparent as possible for Louisville homeowners. You should feel confident making decisions about your roof. That’s why we created our Learning Center and YouTube Channel – to give honest, thorough answers on some of the most common questions homeowners have regarding their roofing system.

By the end of this article, you should be able to identify the likely cause of discoloration on your roof and an appropriate solution. It’s important to fix roof discolorations and their causes as soon as possible to prevent leaks. Although roof repairs are stressful, an issue that would only cost a few hundred dollars to repair can quickly turn into thousands in damages if ignored.  

Let’s dive into 6 possible causes your roof appears discolored and how to fix them:

 1.     Algae on your roof

If you see black streaks on your roof, algae could be the culprit. Algae is one of the most common causes of shingle discoloration. It grows in shady, humid spots on your roof – typically on the North facing slope (although it can grow and spread anywhere on your roof!).

Algae also thrives on shingles because many asphalt shingles contain powdered limestone, which proliferates algae growth on your roof. One of the many reasons we use GAF roofing materials is the StainGuard Plus™ technology found in their shingles are designed to fight off algae formation. They offer incredible warranties on these materials should algae ever form.

Algae on your roof is unsightly and can hinder the curb appeal of your home. Thankfully, the presence of algae does not necessarily mean you need a full roof replacement – or even a repair! There are two ways to get rid of algae – you can hire a company to power wash your roof or ensure that you use algae resistant shingles to prevent growth in the first place. Be sure to contact a top Louisville roofing contractor for a free roof inspection to get their opinion.

 2.     Wind damage to your roof

If you notice sparse black areas on your asphalt roof – you’re not imagining things. This could be the result of high speed wind damage to your roof. If your area has recently experienced 45 mile an hour (or higher) winds, it’s possible your roof has experienced granule loss. If your roof has sustained wind damage, it’s likely you’ll also have some other signs such as missing shingles. Check your gutters and downspouts for tiny black granules to confirm the issue. A reputable Louisville roofing contractor should easily be able to replace any damaged or missing shingles.

 3.     Brown or red rust stains on your roof

Metal and asphalt roofs alike are both susceptible to rust stains. If the discoloration on your roof is brown or red – this is likely due to rust.  

If you have an asphalt roof, a red or brown stain could mean that something major such as your roof ventilation, roof flashing and/or chimney flashing is rusting. It could also be something as small as roofing nails rusting. It’s important to get your roof inspected immediately if you notice a rust stain – as rust can make your roof susceptible to leaks. This is especially true if the flashing around your chimney is beginning to rust. Your flashing is a metal barrier that directs water away from vulnerable parts of your roof, if it’s compromised, a leak will certainly follow.

The rust stain can be treated with a chemical compound, and the source of the rust should be able to be repaired.  

 4.     Moss or tree debris on your roof

If the discoloration on your roof is limited to one particular area – and that area happens to be under a tree, you’ve likely found the cause and solution. If a tree overhangs your roof creating a large shaded area, this creates the perfect condition for moss to grow on your roof. Moss typically starts to grow in green streaks, and if left untreated can grow larger.

Moss is very destructive to your roof and should be treated immediately. Moss can raise your shingles, allowing water to seep through and ultimately causing a roof leak. Shingles that are raised are also more likely to be blown off in the event of a storm (and it’s very likely your insurance policy would not cover the repair due to improper maintenance!). Moss can be power washed off your roof, but will undoubtedly return if you do not take care of the root cause.

 5.     Roof discoloration due to age

Your roof does not age well. After fighting off the elements, weather, pests and debris for years – your roof begins to show signs of wear and tear. A very noticeable sign of an old roof is a faded color. As asphalt shingles age, their granules slowly wear off. The resulting effect is your shingles appear lighter in color. In this instance, discoloration would mean that it’s time for a roof replacement as your shingles are getting past their useful life. If your roof is more than 10-15 years old and you notice shingles appear lighter throughout your roof, it is probably time for a roof replacement.

6.     Asphalt bleed through

Black streaks across your asphalt roof could also be a sign of asphalt bleed through. Asphalt bleed through is another sign of your roof being near or past its useful life. As asphalt shingles start to break down, black pigment from the shingles come up to the surface. A top-rated Louisville roofing contractor should be able to easily distinguish between asphalt bleed through and algae growth on your roof.

Do I need a new roof if my roof is stained?

Discoloration on your roof does not always mean that you need a full roof replacement. Many causes of roof discoloration can be easily repaired if the issue is addressed in a timely manner. Discoloration and its root cause must be attended to quickly to limit damage to your roof. 

Don’t put off having your roof inspected over fear of a large problem. You are most likely costing yourself thousands by doing so!

Final Thoughts

Roof issues are stressful. Whether you have a roof leak, hail damage or are in need of a roof replacement, let us take the stress out of the process. After reading this article, we hope you feel more confident tackling your issue.  

Your home is your biggest asset. Make sure you’re informed about all the parts of your roofing system by visiting our Learning Center and YouTube Channel. 

Next Steps

We always recommend getting a few bids from reputable Louisville roofing companies so you’re able to choose the best one for your home. AIC Roofing and construction has been serving Central Kentucky homeowners since 2003. We’re proud of the best-in-class reputation we’ve earned with Louisville homeowners.

We would love to see if we would be a good fit for your project. If you’re ready to get a free estimate on your roof repair or replacement, contact us today!

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