If you’re considering upgrading your roof to metal but currently have a traditional asphalt or composition shingle roof, you might be wondering if it’s possible to simply install metal roofing over shingles rather than tearing them off. Whether you’re looking to save some money or reduce your environmental impact by avoiding landfill waste, wanting to know how to install metal roofing over shingles is a common question.
In many cases, the answer is yes—it’s possible to install a metal roof over your existing shingles. However, there are several important factors to consider before moving forward with this installation method to ensure the new roof performs as expected.
In this guide, we’ll walk you through the key steps to installing a metal roof over shingles, things to watch out for, and the potential pitfalls if the process isn’t done properly. By the end, you’ll have a clear understanding of whether this approach is the right choice for your home.
The Advantages of a Metal Roof
Metal roofs offer a host of benefits when installed correctly. They are highly durable and capable of withstanding harsh weather conditions like heavy winds, hail, and snow. Their longevity can often surpass traditional roofing materials, potentially lasting decades. Metal roofs are also energy-efficient, reflecting sunlight and reducing cooling costs.
Additionally, they are fire-resistant and can contribute to a home’s overall value. While the initial cost may be higher, the long-term savings and durability make metal roofing a worthwhile investment.
Can You Install Metal Roofing Over Shingles?
Yes, you can install metal roofing over existing shingles, but it’s not always as simple as laying down new metal panels on top of your old roof. Several things need to happen first to ensure the success of this type of roof installation.
First, you’ll need to assess the condition of your existing roof. If the shingle roof is in poor shape—whether due to leaks, missing shingles, or other structural damage—installing a metal roof directly over it won’t solve the problem. These underlying issues need to be addressed first, or they’ll continue to cause trouble even after your new roof is installed.
The installation method of metal roofing is designed to be durable and long-lasting, but it’s crucial to start with a solid foundation. A damaged or weakened roof structure beneath the shingles could lead to problems down the road. While metal roofing is incredibly lightweight compared to other materials, like tile or slate, making necessary repairs or reinforcing your roof is critical before moving forward.
Installing a Metal Roof Over Shingles: What You Need to Know
Once you’ve determined that your current roof is in good shape, the installation of metal roofing over shingles can begin. This process involves a few essential steps that need to be followed carefully to ensure the roof’s longevity and performance.
Roof Inspection and Preparation
Before any work starts, a thorough inspection of the current roof is crucial. A roofing professional will check for structural damage, moisture issues, or rotting wood beneath the shingles. If any repairs are needed, they must be addressed before proceeding with the metal roof installation.
Additionally, the shingles should be flat and intact. Bumps, ridges, or uneven surfaces may affect how the metal panels are installed and compromise the roof’s final appearance and durability.
Underlayment
Once the inspection is complete and repairs (if any) are made, the next step is installing a quality underlayment. This layer provides an additional barrier of protection against water infiltration. Although metal roofs are known for their watertight capabilities, having a secondary line of defense is always a good idea, especially if you’re covering existing shingles.
Furring Strips (Optional)
In some cases, furring strips (also known as battens) may be added over the shingles before installing the metal panels. These strips create a flat, smooth surface for the metal panels and also allow for airflow between the layers. This can help with moisture management and prevent heat buildup.
Metal Panel Installation
Once the preparation is complete, the metal panels are installed. Metal roofing comes in various styles, including standing seam, corrugated, and metal roof shingle designs, so you can choose the look that best fits your home’s aesthetic. The panels are secured using fasteners that are often hidden (concealed fasteners), which not only improve the appearance but also enhance the roof’s resistance to weather elements like rain, wind, and snow.
Final Inspection
After the installation is complete, a final inspection ensures everything has been done correctly, and the new roof is watertight and secure. Professional roofers will check the seams, fasteners, and flashing to ensure there are no weak points where water or pests could enter.
What Happens If You Cover Up a Bad Roof?
One of the biggest mistakes you can make when installing metal roofing over shingles is failing to fix underlying issues first. Installing a new roof over damaged shingles won’t stop existing problems—it will only hide them temporarily. Over time, these issues can worsen, leading to leaks, mold, and structural damage that could be far more expensive to repair later.
If your existing roof has major issues like water damage, cracked shingles, or rotting wood, it’s better to do a full tear-off rather than cover up the problems. Even though metal roofing is known for being lightweight and durable, it can’t make up for a poor foundation. Additionally, improper roof installation can result in gaps, buckling, and other aesthetic and functional issues.
Covering up a bad roof can also void warranties and insurance coverage. Most roofing material warranties require that the substrate (underlying structure) is in good condition for the warranty to remain valid. If the roof isn’t installed correctly or if hidden damage causes problems later, you could be left footing the bill for repairs that would have been avoidable with proper preparation.
FAQs About Installing Metal Roofing Over Shingles
Is it legal to install metal roofing over shingles?
Yes, it’s legal in most areas, but it’s important to check local building codes. Some regions may have specific regulations about how many layers of roofing can be installed.
Does metal roofing over shingles require special preparation?
Yes, the existing shingles must be in good condition, and some preparation, such as adding underlayment or furring strips, may be necessary.
Will installing metal roofing over shingles save me money?
Yes, it can save you money by avoiding the cost of removing the old shingles. However, it’s essential to ensure the old roof is in good condition to avoid costly repairs later.
How long will a metal roof last compared to a shingle roof?
Metal roofing can last 40–70 years, while asphalt shingles typically last 20–30 years. The lifespan of your roof depends on the materials and installation quality.
Can I install metal roofing myself over my shingle roof?
While it’s technically possible, professional installation is highly recommended to ensure proper fit and performance. Mistakes during installation can lead to long-term problems and higher repair costs.
Contact Mountaintop Metal Roofing Today
Deciding to install metal roofing over shingles can be a smart, eco-friendly, and cost-effective choice, but it’s important to do it right. At Mountaintop Metal Roofing, we specialize in ensuring that every roof installation is completed with the highest standards of quality and precision.
Our experienced team can help you determine whether covering your shingle roof with a metal roofing system is the best option for your home or if a tear-off is necessary. For more information or to request a free quote, contact us today!