7 Things That Can Void a Roof Warranty

Serving Bastrop county and other surrounding areas in TX since 2015 and helping homeowners get closer to the perfect vision for their home.

Every new roof usually comes with a warranty of some sort. There are usually two basic warranties that come with a roof – the manufacturer’s warranty that covers the product used and most contractors offer a workmanship warranty that covers mistakes made in the installation process. These warranties can help offset costs for repairs that may need to be done later in the life of the roof. You can learn all about different warranty options for new roofs in our previous blog post, but this article covers mistakes homeowners make that can void their warranties.

Typically, a venting system will pull in air to the lower part of the roof through intake vents and channel that air into the upper parts of the roof where it is dispersed. If the system is working improperly, moisture can get trapped in the attic which creates a thriving environment for mold and mildew to grow. Over time this can cause damage to the roof decking and the shingles will wear and fade, which compromises the structural integrity of the roof and attic space. If you’re having a problem with a roofing product, but the problem originated with faulty ventilation, the roof warranty will most likely be voided. It’s good practice to inspect your ventilation system and make sure that it’s functioning properly.

2. Below Standard installation

Although Manufacturer Warranties are a good thing, the manufacturers that uphold them have very strict installation regulations, which can include a specific nail length as well as a certain number of nails used per shingle. Poor work from a contractor who is unfamiliar with the manufacturer warranty standards could end up voiding the warranty. You want to be careful when selecting a roofing company and make sure that they have a good service record and work consistently with the same quality products. At Butler Contracting, we are GAF certified and work primarily with their products in a consistent manner that keeps your warranty from being voided. At the end of each installation, Butler Contracting will register your roof system warranty with the manufacturer.  This will ensure all the products used on your roof are documented with the manufacturer in the event an issue or a warranty claim arises in the future.

3. Roof Perforations

Be careful where and how a satellite dish or antenna is installed. These installations usually require drilling directly into the exterior of your home, which could be considered “mechanical damage” and void the workmanship warranty. They don’t, however, technically void the entire roof warranty depending on the manufacturer. 


If these accessories are installed incorrectly, they can cause leaks in your home. Before you have one installed on your house, it’s a good idea to check the fine print on how they pertain to warranties for both the contractor and the manufacturer. You also might be asking if solar panels will have the potential in voiding the warranty –  we dedicated an entire article to answering the question.

4. Skylights

Be aware of all roof modifications that require roof penetration and shingle removal. Leaks caused by additions such as skylights have the potential of voiding a warranty. If you want to install a skylight down the road, it’s a good thing to mention it to your roofing contractor before they begin so that you have clarity on how it might affect the roof warranty.

5. Pressure Washing

There’s a lot of debris that can build up on a roof over time (especially if you’re one of those folks that lives near pine trees). One of the more concerning threats to an unmaintained roof is moss and algae. If moss or algae begins to grow on your roof and isn’t cleaned off, it will hold moisture close to the surface and over time will lead to increased frost damage, cracking shingles and other issues.


You may be tempted to get rid of the moss by pressure washing it, but that close-up pressure spray is going to wreak havoc on your asphalt shingles. A better option is to use zing strips near the peak of the roof. Zing strips activate in the rain and release a fungus inhibitor that won’t allow the moss to grow.  Butler Contracting also offers Stain Guard Plus Algae Protection Shingles exclusively from GAF.  These roof shingles have a 25 year limited warranty and are included with the roof system warranties that Butler Contracting offers as a GAF Certified Contractor. 


If you want to have your roof cleaned, make sure to hire a professional that doesn’t pressure wash, but can soft wash your roof with a gentle solution. Make sure that they always angle their spraying downward and not upward spraying under the shingles and flashing.  Butler Contracting has roof cleaning recommendations from GAF and we are happy to share those with you upon request. 

6. Layering new shingles
over old shingles

It’s never a good idea to lay down a new roof on top of an old one. It might save time and money, but only in the short term. Laying new shingles over old shingles may be avoiding the root problem and possibly causing further damage to the roof. If there is a part that is rotted, a layered roof will only prolong the problem and make it worse. In addition to those issues, a whole other set of shingles adds weight on top of the roof that might cause the roof to sag over time. Doing this will certainly void the warranty.

7. Using Different Brands

Some contractors will mix and match brands in building your new roof or making repairs. A roof works efficiently as a system made up of components that are designed to work together. One manufacturer’s flashing doesn’t necessarily work the best with another company’s shingles or underlayment. Every Manufacturer has specific standards that need to be followed in order to maintain the warranty. This is one of the many reasons why Butler Contracting uses GAF roofing systems – it allows us to be very consistent with our work, guarantee our workmanship, and offer the best warranties in the roofing industry by being GAF certified.