Can You Install a Metal Roof Over Shingles?

Key Factors to Consider Before Installing Metal Roofing Over Shingles

If you’re wondering, can you install a metal roof over shingles? The short answer is yes — but there’s more to it than just laying metal panels on top. For many homeowners in Atlanta, metal roofing is an appealing upgrade because it’s durable, energy-efficient, and can boost your home’s curb appeal. But before you dive in, it’s essential to understand the pros, cons, and practical considerations of installing metal roofing directly over existing shingles.

Why Consider Installing Metal Over Shingles?

Replacing an old roof is a significant project, both in terms of cost and disruption. Removing old shingles takes time, creates a mess, and usually increases labor expenses. That’s why some homeowners consider installing a metal roof directly over the existing shingles as a quicker and less expensive option.

In Atlanta, where weather can swing from heavy rains to blistering sun, metal roofs offer significant benefits:

• Longevity: Metal roofs can last 40-70 years, much longer than traditional asphalt shingles.
• Energy Efficiency: Metal reflects sunlight, helping to keep your home cooler during hot Georgia summers.
• Durability: Metal withstands wind, hail, and even fire better than shingles.

So, if your current shingles are still in decent shape, adding metal over them seems like a smart shortcut — and often it is. However, there are important details to consider.

What the Building Codes Say

Before starting any roofing project in Atlanta or elsewhere in Georgia, you need to check local building codes. Most jurisdictions, including Atlanta, allow metal roofing installation over existing shingles — but usually only if there’s one existing layer of shingles.

If your roof already has two or more layers, you’ll likely need to remove the older shingles before installing the metal. This rule helps avoid putting excessive weight on your roof structure, which can lead to safety issues.

Also, some building codes require that your roof deck is in good condition and free of rot or damage before adding another roofing layer. So, even if you’re allowed to install metal over shingles, you should still inspect carefully or have a professional check for hidden damage.

Three Pros of Installing Metal Roof Over Shingles

1. Cost and Time Savings: One of the biggest reasons homeowners ask, ‘Can you install a metal roof over shingles?’ is to save money. Removing old shingles adds labor costs and disposal fees. By skipping that step, you can significantly reduce the timeline of your roofing project.Less demolition also means less debris around your home, which reduces cleanup work and minimizes disturbance to your landscaping or property.
2. Extra Insulation and Sound Barrier: Installing metal roofing over shingles can provide an additional layer of insulation, thereby further enhancing your home’s energy efficiency. Additionally, the extra layers can help reduce noise from rain or hail, resulting in a quieter indoor environment.
3. Environmental Benefits: Leaving old shingles in place reduces landfill waste and makes your roofing project more environmentally friendly. Recycling or reusing roofing materials whenever possible is a smart move for eco-conscious homeowners.

Cons and Considerations Before Installing Metal Over Shingles

• Roof Condition Matters: The most significant risk associated with installing metal roofing over shingles is the potential to conceal existing problems. If your shingles are damaged, curling, or missing in spots, installing metal on top won’t fix those issues. It can trap moisture and cause rot or mold beneath the new roof. Before installation, ensure your roof is structurally sound and free from signs of leaks or damage. If you’re unsure, it’s worth investing in a professional inspection.
• Weight and Structure: Even though metal roofing is lighter than many other roofing materials, layering it over shingles adds extra weight. Your roof framing must be strong enough to support this combined load. An experienced roofing contractor will evaluate your home’s structure and recommend if reinforcement or shingle removal is necessary.
• Ventilation Challenges: Proper attic ventilation is key to a long-lasting roof. Adding metal over shingles can sometimes affect airflow, especially if there’s little space between the old and new layers. This trapped heat and moisture can accelerate wear on your roofing materials. Your contractor may recommend adding special ventilation or an underlayment system to promote airflow and prevent future issues.

How to Prepare Your Roof for Metal Over Shingles Installation

If you decide to install a metal roof over your shingles, preparation is essential for achieving the best results.

• Clean the Existing Roof: Remove debris, dirt, and loose shingles to create a stable base.
• Repair Any Damage: Fix loose shingles, damaged flashing, or signs of rot before starting.
• Install a Proper Underlayment: A high-quality underlayment specifically designed for metal roofs serves as a moisture barrier, providing additional protection against moisture.
• Add Furring Strips if Needed: Sometimes contractors install vertical wood strips to create a ventilation gap and a level surface for metal panels.
• Check Flashing and Seals: Replace or upgrade flashing around chimneys, vents, and edges to ensure a watertight seal.

When Is It Better to Remove Shingles First?

Sometimes, installing metal directly over shingles isn’t the right choice. You should remove old shingles before installing metal if:

• Your roof has two or more layers of shingles.
• The existing shingles are severely damaged or curling.
• You have structural concerns or suspect hidden damage.
• Your roofing warranty requires shingle removal.
• You want to thoroughly inspect and repair the roof deck.

Removing shingles adds upfront cost but provides a clean slate. It also allows your contractor to identify and address any underlying issues that could impact the longevity of your metal roof.

Final Thoughts

Can you install a metal roof over shingles? Yes, it’s possible and often practical — but only if your existing roof meets certain conditions. For Atlanta homeowners, metal roofing offers excellent benefits that make it a wise investment, especially when installed properly.

Before making a decision, consider your roof’s current condition, local building codes, and the long-term impact on your home’s structure and ventilation. A professional roofing contractor can assess your roof, help you weigh your options, and ensure the job is done right. If you’re ready to upgrade your Atlanta home with a metal roof, or if you need reliable roof repair or full roof replacement services, Bumble Roofing of North Atlanta is here to help. Our experienced team knows the ins and outs of metal roofing installations and can guide you every step of the way. Contact us today for a thorough inspection and expert advice. A little planning now will help protect your home for decades to come.