GAF Timberline shingles are among the most popular in the world, and there are many reasons that they enjoy such a following. In fact, this particular line of products are the most popular asphalt shingle products in America as of this writing.

The Timberline series consists of six products, each designed for different tastes and price ranges. Timberline shingles are specifically engineered for durability, visual appeal, and versatility. In spite of all these qualities, these shingles tend to be fairly cheap. This has a lot to do with their continued success in the industry.

The Pros:

Let’s begin by looking at the qualities that have made these products so successful.

Lifetime Warranty

These shingles come with a lifetime warranty, the full text of which can be read here. Right away, we see that there is a way to make this warranty even better. If your roofing system makes use of at least three GAF products (other than the shingles), it is eligible for an extended warranty that covers all four products regardless of any prior coverage or lack thereof.

We can also see that this warranty is transferable, which is nice for those who might want to sell their home. It can only be transferred once per customer, which is obviously meant to prevent any sort of warranty scamming. All in all, this warranty will cover anything that can be classified as a manufacturer defect.

High Durability

GAF Timberline shingles are known for their high durability. They contain a fiberglass mesh which helps to hold the asphalt together and prevent erosion and breakage. Even if the asphalt itself happens to crack, the mesh will probably hold it together for a long time afterward.

Because of this fact, GAF Timberline shingles have a very high impact resistance rating. Some types will have an impact resistance rating as high as four. To put that in perspective, the test for level four impact resistance involves dropping a steel ball onto the shingles from a height of twelve feet. They dropped the ball twice in the same spot, and these shingles obviously survived.

In addition to this, these shingles are thicker than most others on the market. This equals a longer life and better resistance to moisture. The Timberline shingles are affixed to the roof with an adhesive lock that is meant to provide superior wind resistance as well. With proper installation, these shingles can resist winds as high as 130 miles per hour.

Very Good Selection

GAF, being one of the largest and most prolific manufacturers of roofing products on earth, has a very extensive list of colors and shades from which you can choose. These color options don’t seem to change much from year to year, which is very good. If one or a few shingles are damaged, this consistency makes it much easier to find a replacement with a matching color and style.

Protection Against Algae, Mildew And Mold

All GAF asphalt shingles are impregnated with a secret weapon that keeps away mold, mildew, and algae. These materials will discolor your roof and make it look like an abandoned swimming pool or a swampy pond, and nobody wants that. The secret weapon that keeps away these nasty green organisms is copper.

Copper has natural antimicrobial properties, and that’s one reason that it is commonly used for roof flashing and other roof accessories. Of course, a lot of people can’t afford copper accessories, but that’s neither here nor there. It is a fact that copper cannot grow mold, mildew, etc., and Timberline shingles make use of it by coating each granule with a thin layer of copper. Even though there isn’t a whole lot of copper to be found on each granule, it is enough to inhibit microorganisms for the entirety of the product’s life.

Special Qualities

We already mentioned that there were six different lines of Timberline shingles. Although all of these products are similar, each one has unique little bonus features that set it apart from the other. For instance, Timberline American Harvest shingles are engineered for fire resistance, a textured look, and a high level of wind resistance.

For another example, we might look at Timberline Armorshield shingles. These are the most impact-resistant shingle of the line and have that impressive resistance rating that we discussed earlier. They don’t seem to have compromised on the appearance of these shingles, which is impressive.

Part Of A Combined Roofing System

Timberline shingles make up one part of a lifetime roofing system that has been designed to work flawlessly. The idea is to have six products that are meant to work together and complement one another’s features. This eliminates any possible issues with compatibility, and that’s why roofing contractors tend to suggest the whole system rather than just one component.

The combined GAF roofing system includes:

  • Timberline roofing shingles
  • Cobra ridge vents
  • Deck Armor underlayment
  • GAF starter strips
  • Weather watch leak barrier
  • GAF Ridge cap shingles

Qualified Contractor Program

To make sure that their products are installed correctly, GAF has a qualified contractor program that involves training and certification for roofing contractors. There are several ways in which this benefits the customer. The best thing is the fact that you can go to a GAF-certified contractor without worry. Since they have been certified by the company, there will be no doubt that they know how to do the job properly.

Whenever GAF changes its installation standards, all of its certified contractors are re-trained for compliance with the new standards. This training and certification program has several levels, and this will determine the level of warranty coverage that you can receive from their work. The highest level is called “master elite,” so these are the people you want to seek out for your repairs.

The Cons:

There are a few known issues with these types of shingles, so let’s be fair and look at those as well.

Lifetime Warranty Only Covers Manufacturer Defects

We have already talked about the warranty, but there is one little problem here. Unless you can find a “master elite” roofer, the warranty will only cover manufacturer defects. In practice, this means that the company will only cover damages that can be proven to have been caused by a defect at the factory. There is a 25-year limited warranty against mold and mildew damage, so that’s kind of nice. Still, it can be very hard to get the company to cover damage resulting from faulty installation. Since they go to a lot of trouble to make sure that all their contractors are trained properly, one would think that they would be willing to guarantee that work.

Not A Lot Of Texture Variation

Regardless of which type of Timberline shingle you get, the appearance will be more or less the same. This is because all of these products have a similar style and texture. There is a lot of variation in terms of their construction and performance, but none of that will make any difference in the visual appeal of your home. It would be nice if they had a little more variety here. To be fair, GAF does have a huge variety in terms of color, but the selection of styles could offer a little bit more.

Not Good With Aluminum Gutters

The copper-coated granules that give Timberline shingles their algae/mold resistance have an unfortunate side effect. Over time, these granules will gradually wear away. As they are knocked and pulled loose by the elements, most of them will slide down the roof and end up in the gutters. If you have ever found what looks like black sand in your gutters, it was probably just the granules from your shingles.

Copper-coated granules can sometimes react with aluminum in a strange way. Because copper and aluminum have different electrical potentials, an electric charge is produced when both of them are suspended in water. Of course, it has to be the same jar or puddle of water for this effect to occur. However, it sometimes occurs when copper granules from the asphalt shingles come in contact with the bottom surface of an aluminum gutter.

The result is that the metal with the lower electrical potential begins to corrode. In this case, the aluminum is the less electrically conductive metal, and so it will be eaten away in the same way that rust eats steel. If your gutters are particularly thin, you could end up with some serious leakage in no time flat.

Product Reviews

We have finished examining the pros and cons, so let’s take a look at two random product reviews so that we can get a sense of how satisfied GAF’s customers really are. First, let’s look at this one. This reviewer gave Timberline shingles a rating of 4.4 out of 5, which is quite good. Their reasons included a wide variety of colors, the convenience of the 6-component roofing system, and the high level of wind resistance. Their only real complaints came from the sometimes-confusing nature of the warranty.

Here’s another set of reviews to consider. Here, we can see that most of the buyers on this site gave the product a 5-star rating, indicating that they could not be happier with the results. Reasons cited include the attractive texture and the fact that each shingle is sealed to the roof. All in all, we are surprised to see that there are almost no negative reviews.


GAF Timberline shingles have become the industry standard, and so it is not surprising to see that their pros outnumber their cons. That being said, the cons should not be totally disregarded. Several of the disadvantages of these shingles relate directly to the warranty. Like all warranties, it has certain conditions that have to be met. Also, there are a number of ways in which you can accidentally void your warranty. Either way, GAF isn’t the only company that has a complex warranty system. In fact, some major roofing suppliers have much more complicated multi-tier systems that make GAFs’ warranty look simply by comparison.

In the end, we only see one real problem with these shingles, and that is the fact that they should not be used with aluminum gutters. To be honest, that is a significant problem. Aluminum gutters are the cheapest and most common option, so you will likely have to spend a little bit of money to get gutters that are made of a different material.

In spite of these flaws, we see a lot of great things. GAF obviously went to a lot of trouble to make these products very tough and resilient. We can’t think of a single type of damage that they did not address. These shingles hold up well against impact, fire, moisture, wind, algae, mold, mildew, and just about anything else that mother nature has in her bag of tricks. If you have found this article to be helpful, we hope that you will fill out the contact form below.