If you have never worked in roofing, you probably have not given much thought to the granules on your asphalt shingles. Perhaps you just thought they added an attractive texture to the shingles and not much else.

However, those granules are key components to almost everything your roof does to protect your house or commercial property. Understanding why they are essential is vital to the lifespan of your roof.

Once you understand how important these granules are, you will be more motivated to protect those granules from loss, to watch for signs of deterioration in your shingles, and to take timely action to maintain your asphalt shingle roof. This will help prevent further damage to your roof and home and save you money and time in the long run.

What Is the Purpose of Granules on Roof Shingles?

As mentioned above, you probably noticed that the granules, which are made of crushed stone or minerals and a ceramic coating, add attractive color and texture to your new roof. However, those granules also contribute to the stability and function of your roof in many ways:

Granules give shingles the ability to shed water – one of the main purposes of your roof is to keep rain and snow out of your house. The granules cause the water to slide off the shingles and flow down the roof, which is exactly what you want from your shingles. With granule loss, water is more likely to sit on the roof and eventually soak through.

The granules also provide UV resistance, which helps keep sunlight from deteriorating your roof. This can increase the life of your roof and decrease long-term repair and replacement costs. Think of granules as sunscreen for your most valuable investment.

Some granules are even coated in a way that reflects sunlight. This is especially important in warmer climates such as what we have here in Alabama since this can keep your home cooler and even improve your home’s energy rating. Granule loss might drive up cooling bills.

Granules increase fire resistance. While in most areas of the country, we usually think of fire as coming from inside a home from the stove or electrical malfunction, if a nearby house is on fire or an outside power line sparks, resistance to wind-blown sparks or fiery debris is critical. While no roofing material is 100% indestructible, the more resistance you have, the more time you buy for firefighters to protect your home from loss and damage.

Your shingles’ granules also help resist algae and moss growth. Have you seen black streaks on a roof? Those streaks are usually caused by blue-green algae growth on the shingles. Some types of asphalt shingles are specifically designed to resist algae even more efficiently by adding copper to the granules, and the loss of granules ends this protection. The algae itself isn’t usually harmful, but it can retain moisture, leading to shingle damage and rotting.

From the construction side of things, granules on your asphalt shingles also keep the shingles from sticking together during packing, distribution, and installation. And they provide some traction on the roof for the roofing contractors who are installing.

The Causes of Shingle Granule Loss

Some loss of granules is inevitable and normal since your roof is continually exposed to the elements. But some can be prevented or at least reduced. Plus, knowing what causes damage will help you inspect your roof at the right times for possible damage.

POWER WASHING – While it is OK to wash your roof if needed, especially if some algae is present, power washing is an absolute no-go for granule coated asphalt shingles. The force of the water is far more than normal water flow and will loosen and dislodge granules, then wash them away. Plus, if your roof has so much black on it that it needs power washed, you may already have granule-loss damage that needs to be addressed instead of just washing away the evidence.

LIMBS & WIND-BLOWN DEBRIS – Trees near your home provide excellent southern shade, but regular maintenance of trees near your roof is critical to protect your shingles. Limbs that brush against the roof can scrape off granules, decreasing the effectiveness of your shingles’ coating. Debris that lands on your roof from nearby trees or from other sources can also be a culprit.

DEBRIS FROM THE GUTTERS – Keeping your gutters clean is always critical to roofing maintenance, but this is especially true for asphalt shingle roofing. Debris that washes up onto the roof from the gutters can sand away granules and wash them down into the gutter.

FOOT TRAFFIC – While there may be times when you or a contractor need to walk or climb on your roof, such as when cleaning difficult to reach gutters, it is important to minimize traffic on your asphalt shingle roof as much as possible. And when you or your contractor have been on the roof, watch for signs of granule loss that might have occurred. It is better to repair a small number of shingles with granule loss than to have the loss lead to bigger damage.

HAIL & STORM DAMAGE – Of course, the most common source of damage to roofs is storm damage. Heavy winds and even a small amount of hail can wreak havoc on your shingles and especially on the granule coating. After a heavy storm, be sure to inspect for damage. Again, catching small areas of damage is better than having them lead to large leaks down the road. This is especially true if you have a newer roof. Even new asphalt can be damaged by a big storm, and you don’t want to waste the money you just spent on replacing it.

Using A Roof Rake – Often when you are using a roof rake to clean the snow off your roof, you can displace a lot of the granules. You should use great caution to assure you are not putting much friction on the shingles. 

Is it Normal for a New Roof to Lose Granules?

Yes, when your new roof is installed, you may notice more loose granules stuck in your gutter guard at first. The handling and cutting that occurs during installation may loosen some granules, and those will be washed away during the first few storms. This is a little like finding loose hair on your shirt after a haircut and is completely normal.

Also, some minor loss will be ongoing throughout the normal life of your roof as it is continually exposed to the elements. However, if you see balding spots on a new roof or large amounts of granule loss, especially from specific areas of the roof, the shingles may not have been installed correctly. Or some of the shingles could be defective from the manufacturer. That is more likely if you see blisters or peeling on new shingles. It is a good idea to contact your contractor as soon as possible if you have any of these concerns. Your roofing contractor should work with you to make this right and to get replacement shingles from the manufacturer if they are defective.

 
When to Call a Professional

Excessive black streaks – Since granules discourage algae growth, lots of algae on your roof could be a sign of granule loss.

After any hailstorm – Hail is probably the number one enemy of your roofing granules, striking with force and usually followed by hard wind and rain. Hail damage can be difficult to see from the ground, and a fast, professional assessment protects you if you have need to make an insurance claim to get the roof repaired.

Loose shingles – Sometimes a storm won’t cause damage to your entire roof, but the wind may catch a few shingles and pull them loose. This is the kind of repair that can save your roof and the decking and attic underneath it. Water that gets in under loose shingles can flow into more areas of your roof and home and cause significant general damage. Also, if you are tempted to staple loose shingles down, know that this is no longer allowed in new construction because staples come loose more easily in the wind.

Bald spots –  If you can visibly see that your shingles are going bald, this is an urgent situation. This is the kind of damage that shows on older roofs that have had years of wear and usually means it’s time to replace your shingles. Bald is not normal.

Noticeable increase in granule loss –  If you are seeing more granules in your gutter or on the ground than ever before, your roof may be starting to deteriorate. Even if it’s not quite time for replacement, a good contractor can let you know how much time you probably have left on your roof, repair any areas that are more significantly damaged, and give you an estimate for overall replacement cost.

Before an inspection – If you are considering changing homeowners’ insurance, and the switch requires an inspection, call your local contractor first. Better for you to find out about any issues that may come up with the insurance company before they inspect your home. You may also decide to replace or repair the roof before the inspection to help increase your chances of approval or bring down your rates.

Before putting your home on the market – Making sure your roof is in good condition and having written proof from a recent inspection is a great tool for marketing your home. Prospective home buyers will appreciate a home that does not need major work on the roof right away, and this may help you sell your home more quickly. Your Alabama contractor can also help you understand the costs of roof repair or replacement, which can help you decide whether to make those investments before selling the home. Talk to your contractor, then to your real estate agent, and decide if you will be able to sell the home for enough to pay for or profit from the new roof.