Can You Put a Metal Roof Over Shingles? Pros, Cons, and Cost

by | May 3, 2024 | Roofing

Can You Put a Metal Roof Over Shingles Pros Cons and Cost

Yes, placing a metal roof over existing shingles is entirely feasible. This choice can save both time and expenses by skipping the laborious removal of shingles. But remember, it's not just about slipping on a metal shell; the condition of the current shingles and the ability of your roof to handle additional weight must be considered. Calling in a seasoned roofing contractor ensures you're not ignoring any lurking issues that could spell trouble later. Proceeding well informed will open the door to new possibilities.

Yes, it is possible to install a metal roof over shingles. However, it's essential to ensure that the existing roof structure can support the additional weight and to consult with a professional roofer to assess the specific requirements for your property.

Metal roof over shingles

Can You Put A Metal Roof Over Shingles?

When contemplating a roof replacement, installing a metal roof over existing shingles can offer an efficient alternative to the laborious process of shingle removal and disposal, thereby reducing both labor costs and time. However, the decision to pursue this approach warrants careful consideration. Consulting a professional roofing contractor to evaluate the current state of your roof is essential to ensure both structural integrity and durability for your new metal roof.

It's crucial to bear in mind that the condition of your existing shingles significantly affects the feasibility of installing a metal roof over them. If the shingles are curling, damaged, or exhibit any signs of moisture damage or rot underneath, simply covering them with a new metal roof might exacerbate underlying issues, potentially leading to more extensive and costly repairs in the future. Hence, it's imperative to have a thorough inspection conducted by a qualified roofing professional to assess if your existing shingles are suitable for being covered by a metal roof.

This situation is analogous to building a beautiful new house on an old, crumbling foundation—eventually, it's unlikely to support everything on top of it. Likewise, dressing up old problematic shingles with a new metal roof could perpetuate a pre-existing issue without addressing its root cause.

It's also vital to consider the local building codes and regulations in your area while making this decision. While many areas permit metal roofing over shingles, some jurisdictions have specific requirements that must be adhered to ensure compliance with safety standards.

Moreover, evaluating the weight of additional metal roofing material is equally important to determine if your current roof structure can support it without compromising its integrity. A trusted roofing professional will conduct a comprehensive assessment of your existing roof structure to verify its capability to bear the added load before installation.

By taking these factors into account, you can make an informed decision about whether installing a metal roof over shingles is right for your home.

Pros and Cons of Installing a Metal Roof Over Shingles

Metal roof over shingles

The idea of installing a new metal roof over old shingles may seem like a money-saving convenience, and here's why:

Pros

Time and Cost Efficiency: One significant benefit is avoiding the costly expense associated with shingle removal. By installing a metal roof over existing shingles, you save time and labor costs related to removing the old shingles. It serves as a great cost-effective strategy, especially if your existing shingles are in good condition.

Added Insulation: Layering a metal roof over shingles provides potential for added insulation. This extra layer can offer increased thermal protection, potentially enhancing the energy efficiency of your home. The space between the old shingles and the new metal roof functions as an air pocket, creating an additional barrier against heat loss in winter and heat gain in summer.

Cons

Weight Considerations: Before adding another layer of roofing material, it's essential to assess whether your home's structure can bear the additional weight. The combined weight of multiple layers can exceed the load capacity of the structure, potentially leading to structural issues over time.

Potential Trapped Moisture: Without proper ventilation between the old shingles and the new metal roof, moisture can become trapped, potentially leading to mold or rot. Proper installation techniques and ventilation measures must be carefully followed to mitigate this risk effectively.

Balancing these pros and cons plays a crucial role in making an informed decision when considering whether to install a metal roof over existing shingles. It's important to weigh these factors against your specific circumstances and needs to determine if this approach is suitable for your home.

With an understanding of the advantages and potential drawbacks of placing a metal roof over shingles, let's take an in-depth look at how this process unfolds in action.

Installation Process for a Metal Roof Over Shingles

Metal roof installation steps

Transitioning from shingles to a metal roof involves careful planning and precision to ensure a successful installation. Let's break down the steps involved in this process:

Step 1: Roof Inspection

The first step is examining the current condition of your roofing system, from the existing shingles to the roof's structure. This comprehensive inspection reveals hidden issues such as rotting wood beneath the shingles, water damage, or leaks—crucial problems that must be resolved before installing the metal panels.

Step 2: Adding Underlayment

Once repairs are completed, protecting your roof with a secure underlayment over the existing shingles becomes paramount. The underlayment serves as a necessary barrier against moisture, preventing mold growth and premature deterioration while improving energy efficiency within your home.

Step 3: Installing the Metal Roof

With the underlayment laid down, the installation of the metal roofing panels can begin. Each panel needs to be strategically positioned to overlap with adjacent ones, ensuring a strong and unified covering that shields your home from external elements.

Thus, by carefully executing each step in installing a metal roof over shingles, you're not only enhancing the structural integrity of your roof but also elevating its performance capabilities for years to come.

This meticulous approach sets the stage for understanding why removing existing shingles is essential when transitioning to a metal roof.

Necessity of Removing Existing Shingles

Shingle removal process

The question of whether to remove existing shingles before installing a new metal roof is pivotal. The condition of the underlying shingles determines this decision—durability and evenness are paramount, as the new metal roof's reliability hinges on its foundation.

Shingles severely damaged due to weather, age, or improper installation might create a lumpy surface, making it futile to install a new metal roof over them. It's similar to adorning an unkempt canvas with a fresh coat of paint—the unsightly bumps and lumps from the damaged shingles will eventually show through.

If you lay a new metal roof over severely damaged or uneven shingles, any movement in the foundation can be amplified, potentially leading to visible imperfections. Not only marring the aesthetic appeal but also impacting the performance and longevity of the metal roofing system.
The second crucial consideration is local building codes and regulations. Various building codes mandate that no more than two layers of roofing should be present on any structure–meaning if there are already two layers in place, both need removal before installing the metal roof to comply with these regulations.

Before making a choice regarding whether to remove existing shingles or not, discussing this with a professional roofer becomes indispensable.

The Role of Professional Roofer Consultation

Seeking consultation from an experienced roofing professional significantly factors into making an informed decision about your roofing project. Their expertise can provide essential insights into unseen issues lurking beneath the current shingles. By performing a thorough inspection, they can identify hidden problems with the wood decking or moisture-related issues that necessitate the removal of existing shingles.

Picture consulting with a skilled roofer as akin to visiting a knowledgeable doctor for an ailment—you trust their judgment because they have seen similar cases and can prescribe tailored solutions to meet specific needs.

In essence, while it is not always mandatory, speaking with a roofing professional ensures that your decision aligns not only with your preferences but also adheres to local building codes and standards.
Remember: Regular maintenance checks on your existing roof can prevent situations where extensive damage necessitates removing existing shingles before installing a metal roof.
As we move forward to explore the preparation phase for installing a metal roof, let's delve into vital steps and key considerations for ensuring a successful roofing project.

How to Prepare Your Roof for Metal Installation