Can You Shingle Over Shingles

Many homeowners ponder whether adding a new shingle roof over an old roofing layer is a good idea. It’s crucial to understand the pros and cons of such a decision, especially when dealing with a shingle roof that may already have multiple roofing layers.

Are you looking to replace your roof and wondering if you can shingle over shingles? While it may seem like a cost-effective and time-saving solution, there are several considerations to keep in mind before taking this route. 

Are you unsure about the best approach for your roofing needs? Don’t navigate these decisions alone! The experts at Preferred Roofing can provide you with personalized guidance and solutions tailored to your unique situation. We’re here to help ensure your roofing decisions are sound and beneficial in the long term.

Considerations Before Putting New Shingles Over Old

Comparison roof top before and after cleaning moss lichen high pressure water cleaner tile

Before deciding to put new shingles over old ones, it is important to consider a few key factors.

Evaluating the Condition of Current Shingles

First and foremost, you need to assess the condition of your current roof. If there are any signs of damage or deterioration, such as leaks, rot, or sagging, it’s best to address these issues before proceeding with a new layer of shingles. Ignoring existing problems can lead to further damage and compromises the longevity of your new roof.

Additionally, if your current shingles are already on their second layer or have been in place for a long time, adding another layer can make the roof excessively heavy and cause structural issues. For instance, if you have an existing roof with cedar shakes or asphalt shingles showing signs of curling or moisture damage, it’s essential to consult with roofing contractors before proceeding.

Understanding the Weight Impact on Your Roof

The weight of multiple layers of shingles can put excessive stress on your roof’s structure. It is crucial to determine if your roof can withstand the extra weight without compromising its integrity. To make this assessment, it is recommended to consult with a professional roofer who can evaluate your roof’s load-bearing capacity and provide expert advice. They may suggest removing the existing shingles to avoid potential structural problems down the line.

Checking Local Building Codes

Checking local building codes is another important consideration before shingling over existing shingles. Building codes vary by location and may have specific requirements regarding roofing materials, installation methods, and maximum number of layers allowed. It is essential to consult your local building department or a licensed contractor to ensure that you are complying with all applicable regulations. Failure to adhere to these codes can result in costly fines or even having to redo the entire roofing project.

Considering Aesthetics and Long-Term Value

When considering whether to shingle over existing shingles, it’s essential to think about both aesthetics and long-term value. While adding another layer of shingles may be a quicker and more cost-effective solution in the short term, it’s important to consider the overall appearance of your roof. A second layer of shingles can create a thicker and less uniform look, which may not be visually appealing.

Furthermore, shingling over existing shingles can affect the long-term value of your home. If you plan on selling your property in the future, potential buyers may view a roof with multiple layers as a potential red flag and may request a roof inspection or even negotiate the asking price accordingly.

Moreover, home inspectors often advise new owners to be wary of multiple layers on a roof, as irregularities can hide defects and affect the home’s overall value. In some cases, it may be more advantageous to invest in a complete tear-off and re-roofing project, as it can provide a fresh start with a clean slate and potentially increase the value of your home.

Advantages of Shingling Over Existing Shingles

Cost-Effectiveness

Shingling over existing shingles can be a cost-effective option, as it eliminates the need for a complete tear-off and disposal of the old shingles. This can result in savings on labor and materials, making it a more affordable solution.

Time-Saving

In addition to being cost-effective, shingling over existing shingles can also save you time. Since there is no need for a complete tear-off, the installation process can be completed more quickly. This means less disruption to your daily routine and a shorter timeline for completing the roofing project.

Adding an Extra Layer of Insulation

Shingling over existing shingles can provide an additional layer of insulation to your roof. This extra layer can help improve energy efficiency by providing better thermal resistance and reducing heat transfer. It can also act as a barrier against noise, making your home quieter and more comfortable.

Protection from Weather Elements

Shingling over existing shingles can offer added protection from the weather elements. The extra layer of shingles acts as a shield, providing an additional barrier against rain, snow, and other harsh weather conditions. This can help extend the lifespan of your roof and prevent potential leaks or damage.

Disadvantages of Shingling Over Existing Shingles

While shingling over existing shingles can have its advantages, it is important to consider the potential disadvantages as well. By being aware of these drawbacks, you can make an informed decision about whether or not this option is right for your home.

Potential for Underlying Damage

One of the potential disadvantages of shingling over existing shingles is the risk of underlying damage. Since you’re not removing the old shingles, it can be difficult to assess the condition of the roof deck and any potential issues that may exist underneath. If there are any hidden problems, such as rot or structural damage, they may go unnoticed and could worsen over time if not addressed properly.

Shorter Shingle Lifespan

Another drawback of shingling over existing shingles is that it can result in a shorter lifespan for the new shingles. The underlying layer of old shingles may not provide a smooth surface for the new shingles to adhere to, which can affect their performance and durability. Over time, this could lead to premature wear and tear, requiring you to replace the roof sooner than expected.

Voiding Shingle Warranty

It is important to note that shingling over existing shingles may void the warranty on the new shingles. Most manufacturers specify that their products should be installed directly on a clean, flat surface. By layering new shingles over old ones, you may not meet the requirements outlined in the warranty, leaving you responsible for any future repairs or replacements.

Alternatives to Shingling Over Shingles

If you’re considering shingling over existing shingles but are concerned about the potential drawbacks, there are alternatives you can explore.

Complete Roof Replacement

If you’re worried about the potential risks of shingling over existing shingles, it may be worth considering a complete roof replacement. While this option requires more time and money upfront, it offers several benefits in the long run. By removing the old shingles and evaluating the condition of the roof deck, you can address any underlying damage, ensuring a solid foundation for the new roofing materials. Additionally, a full roof replacement allows you to choose from a wider range of roofing options, styles, and colors, giving your home a fresh new look.

Partial Roof Replacement

If a complete roof replacement seems too daunting or expensive, you could also consider a partial roof replacement. This involves removing the old shingles in areas that are most damaged or where leaks occur. By targeting specific problem areas, you can address any underlying issues and install new shingles to improve the overall performance and appearance of your roof.

Tips from Professionals on Shingling Over Shingles

When is It Advisable?

Shingling over existing shingles may be an option in certain situations, but it’s important to consider the advice of professionals. Here are some tips on when it may be advisable:

1. Minimal Damage: If the existing shingles are in relatively good condition with only minor damage or wear, shingling over them may be a viable option. However, it’s essential to have a professional assess the condition of the old shingles to ensure they can provide a sturdy base for the new ones.

2. Single Layer: Shingling over existing shingles is generally not recommended if there are multiple layers already in place. Adding another layer can increase the weight and strain on the roof structure, potentially leading to future problems. It’s best to consult with a roofing expert to determine if adding another layer is safe and feasible for your specific roof.

3. Proper Ventilation: Adequate ventilation is crucial for the longevity and performance of your roof. If your current roof lacks proper ventilation, shingling over the existing shingles may not be a suitable solution. It’s important to address any ventilation issues before considering this option to prevent potential problems in the future.

What to Look Out for?

When shingling over existing shingles, there are a few things to look out for to ensure a successful installation:

1. Uneven Surface: The old shingles may have become warped or uneven over time. It’s important to inspect the surface and make any necessary repairs or adjustments before installing the new layer. This will help ensure a smooth, uniform finish and prevent potential issues with water runoff.

2. Hidden Damage: While the existing shingles may appear to be in good condition on the surface, there could be hidden damage underneath. Make sure to thoroughly inspect the roof and address any underlying issues before proceeding with the shingling process. This includes checking for rot, mold, or structural damage that may have been concealed by the old shingles.

3. Proper Installation: When shingling over existing shingles, it’s crucial to follow proper installation techniques. This includes using nails of the appropriate length and quality to ensure a secure hold on both the old and new layers. It’s also important to overlap the new shingles correctly and seal them properly to prevent water infiltration.

What is the lifespan of a roof that has been layered with new shingles over the old ones?

The lifespan of a roof that has been layered with new shingles over the old ones can vary. However, it is generally recommended to remove the old shingles before installing new ones for better long-term durability and to prevent potential issues such as excessive weight and uneven surfaces.

Final Thoughts

In conclusion, shingling over existing shingles can be a viable option for certain situations. However, it is important to consider the factors mentioned earlier, such as the condition of the old shingles and any hidden damage that may be present. By addressing these issues before installing the new layer, you can ensure a smoother, more durable roof.

If you’re a homeowner in Willmar, Litchfield, or the surrounding areas, and you’re considering shingling over existing shingles, don’t hesitate to contact us at Preferred Roofing. We have a team of experienced professionals who can thoroughly inspect your roof, assess its condition, and provide you with expert advice on the best course of action. Whether it’s removing the old shingles or shingling over them, we’ll ensure that the job is done right.