Should You Put A Roof Over A Roof?

Thinking about adding another layer of protection to your home? The age-old question of whether or not to put a roof over a roof has sparked much debate among homeowners. In this article, we will explore this topic from various angles to help you make an informed decision. From examining the benefits and drawbacks to exploring the different materials and costs involved, we’ve got you covered. So, before you climb up that ladder, let’s dig into the details and discover if putting a roof over a roof is the right choice for you.

Pros of Putting a Roof Over a Roof

Increased Durability and Protection

Putting a roof over a roof can significantly increase the durability and protection of your home. By adding an extra layer of roofing materials, you create an additional barrier against the elements. This double layer of protection can help to prevent leaks, reduce the risk of damage from hail or heavy snow, and increase the lifespan of your roof. It also provides an extra shield against UV rays, which can cause premature aging and deterioration of the roof.

Energy Efficiency

Another advantage of putting a roof over a roof is improved energy efficiency. The additional layer of insulation and roofing materials can help to reduce heat transfer, keeping your home cooler in the summer and warmer in the winter. This can result in lower energy bills by reducing the need for air conditioning and heating systems. Additionally, by reducing the energy consumption of your home, you are also decreasing your carbon footprint, contributing to a more sustainable living environment.


Putting a roof over a roof can be a cost-effective solution for homeowners. Instead of completely removing the existing roof and replacing it, which can be a costly and time-consuming process, adding a new roof layer eliminates the need for extensive labor and materials. This can result in significant cost savings compared to a full roof replacement. Additionally, the added protection and energy efficiency provided by the new roof can help to lower maintenance and utility costs in the long run, making it a wise investment for homeowners.

Cons of Putting a Roof Over a Roof

Added Weight on the Structure

One potential drawback of putting a roof over a roof is the additional weight it adds to the structure. While modern roofing materials are designed to be lightweight, the accumulated weight of multiple layers can strain the structural integrity of the building. It is important to consult with a structural engineer or a professional roofing contractor to assess the load-bearing capacity of your home before proceeding with this option. If the existing structure is not strong enough to support the added weight, it may lead to structural problems in the future.

Related articles you may like  Do 40 Year Shingles Really Last 40 Years?

Reduced Aesthetics

Adding a roof over a roof may result in reduced aesthetics, especially if the existing roof is visible from certain angles. The new layer of roofing materials may alter the appearance of the roofline and may not seamlessly blend with the existing roof. This can be a concern for homeowners who value the visual appeal of their home, particularly if they live in a neighborhood with strict aesthetic guidelines. It is important to consider the visual impact and potential impact on property value before deciding to put a roof over a roof.

Potential for Moisture Issues

Another consideration when adding a roof over a roof is the potential for moisture issues. Moisture can get trapped between the two layers of roofing materials, leading to the growth of mold and mildew, as well as rotting of the underlying structure. Proper installation, including the use of vapor barriers and adequate ventilation, is crucial to minimize the risk of moisture problems. Regular inspections and maintenance are also necessary to identify and address any moisture issues promptly. Homeowners should be aware of this potential risk and take appropriate measures to ensure proper moisture management.

Considerations Before Adding a Roof Over a Roof

Evaluation of Existing Roof Condition

Before deciding to put a roof over a roof, it is essential to evaluate the condition of the existing roof. If the current roof is damaged, has significant leaks, or is nearing the end of its lifespan, it may be more practical and cost-effective to opt for a full roof replacement instead. A professional roofing contractor can assess the condition of the existing roof and provide recommendations on the best course of action.

Structural Analysis

As mentioned earlier, a structural analysis is crucial to determine whether the existing structure can support the additional weight of a new roof layer. Hiring a structural engineer or consulting with a professional roofing contractor will help ensure that your home’s structural integrity is not compromised. They can evaluate the load-bearing capabilities of the building and recommend any necessary reinforcements or modifications to accommodate the extra weight.

Local Building Codes and Regulations

Before undertaking any roofing project, it is essential to familiarize yourself with the local building codes and regulations in your area. These regulations dictate the permitted roofing materials, installation methods, and overall construction standards. Failure to comply with these codes can result in fines or penalties and may even require you to remove the added roof layer. Contact your local building department or consult with a professional roofing contractor who is knowledgeable about the local regulations to ensure compliance with all necessary rules and requirements.

Different Methods of Putting a Roof Over a Roof

Retrofitting with Metal Roofing

One method of putting a roof over a roof is by retrofitting with metal roofing. Metal roofs are lightweight, durable, and have a long lifespan, making them an excellent choice for homeowners looking to add an additional roof layer. Metal roofing can be installed directly over the existing roof, eliminating the need for extensive removal and reducing labor costs. The reflective nature of the metal helps to improve energy efficiency and can lower heating and cooling costs.

Installing a Built-Up Roofing System

Another method is installing a built-up roofing system, also known as a “roof-over” system. This involves installing multiple layers of roofing materials, typically consisting of asphalt or gravel, over the existing roof. The built-up roofing system provides excellent waterproofing properties and can withstand extreme weather conditions. It is a popular choice for commercial buildings but can also be used for residential properties.

Related articles you may like  What Is The Area Under The Roof Overhang Called?

Using Roofing Membranes

Using roofing membranes is another option for putting a roof over a roof. Roofing membranes are thin, flexible sheets that provide effective waterproofing and can be applied directly over the existing roof. They are lightweight and easy to install, making them a popular choice for homeowners looking to add an additional layer of protection. Roofing membranes also offer good energy efficiency and reflectivity, reducing the heat absorbed by the roof and improving overall energy performance.

Pros and Cons of Each Roofing Method

Metal Roofing


  • Lightweight and durable
  • Long lifespan
  • Reflective, improving energy efficiency
  • Resistant to fire, rot, and pests


  • Can be more expensive upfront compared to other roofing materials
  • Requires professional installation for optimal performance

Built-Up Roofing System


  • Excellent waterproofing properties
  • Can withstand extreme weather conditions
  • Suitable for flat or low-slope roofs
  • Offers thermal insulation


  • Heavier than other roofing materials, potentially straining the structure
  • Requires professional installation due to the complex layering process

Roofing Membranes


  • Lightweight and easy to install
  • Effective waterproofing properties
  • Reflective, improving energy efficiency
  • Can be installed with minimal disruption


  • May require routine inspections and maintenance to ensure longevity
  • Limited lifespan compared to other roofing materials

Factors to Consider when Choosing Roofing Materials

Climate and Weather Conditions

One of the most important factors to consider when choosing roofing materials is the climate and weather conditions in your area. If you live in an area prone to high winds, heavy rains, or frequent hailstorms, you will need roofing materials that are resistant to these weather elements. Additionally, consider the average temperature range in your region and choose materials that provide adequate insulation and energy efficiency based on the local climate.

Available Budget

Your budget is another significant factor when selecting roofing materials. Different materials have varying costs, and it’s essential to choose materials that are within your price range. However, it’s important to remember that investing in high-quality materials may save you money in the long run, as they tend to have longer lifespans and require less maintenance. Consider the overall value and lifespan of the roofing material before making a decision solely based on upfront costs.

Expected Lifespan

The lifespan of the roofing materials should also be considered. Some materials, such as metal or slate, have longer lifespans compared to asphalt shingles. Although these materials may have higher upfront costs, they provide excellent durability and typically require fewer repairs and replacements over the years. Evaluate the expected lifespan of the materials and compare it to your long-term goals and plans for the property.

Common Issues and Maintenance Considerations

Condensation Problems

When adding a roof over a roof, condensation can become a potential issue. The trapped air and moisture between the two layers of roofing materials can create an environment conducive to condensation. To mitigate this issue, proper ventilation and insulation should be installed during the roofing process. Adequate ventilation will help to minimize moisture buildup, while insulation will reduce temperature fluctuations and minimize the risk of condensation forming.

Drainage and Gutters

Proper drainage and functioning gutters are essential for any roof, especially when adding a roof over a roof. It is important to ensure that the new roof layer does not impede the proper flow of water and that the gutters are clean and free from debris. Regularly inspect and clean your gutters to prevent water buildup, which can lead to leaks and damage to both the existing and new roofing materials.

Related articles you may like  Roofing Contractors Ravenswood, WV

Regular Roof Inspections

Regular roof inspections are crucial to identify and address any issues or damage promptly. With multiple layers of roofing materials, it can be more challenging to spot potential problems, such as leaks or structural issues. Engage the services of a professional roofing contractor to conduct regular inspections, ideally at least once a year. They can identify and address any issues early on to prevent further damage and ensure the longevity of the roof over a roof.

Alternatives to Putting a Roof Over a Roof

Roof Replacement

If the existing roof is in poor condition or nearing the end of its lifespan, a full roof replacement may be a better option than putting a roof over a roof. While it may involve higher costs and more labor, a full roof replacement allows for a fresh start and ensures that the underlying structure is in good condition. This can be especially important if there are extensive damage or structural concerns with the existing roof.

Roof Repair

If the existing roof has minor damage or leaks in isolated areas, roof repair may be sufficient to address the issues. Roof repair involves fixing damaged sections or replacing individual shingles, flashing, or other roofing components. It is a more targeted approach compared to adding an entire new roof layer. Roof repair can be a cost-effective option if the overall condition of the existing roof is still good and only small repairs are needed.

Installation of Insulation

Instead of adding a roof over a roof solely for additional insulation, another alternative is to install insulation directly under the existing roof. This can be achieved by placing insulation materials between the rafters or in the attic space. Proper insulation helps to regulate temperature, improve energy efficiency, and reduce heat transfer, similar to adding a new roof layer. This option may be more suitable for homeowners who do not require the added protection of multiple roofing layers.

Choosing a Professional Roofing Contractor

Experience and Expertise

When selecting a professional roofing contractor, experience and expertise are essential criteria to consider. Look for contractors who have extensive experience in installing roofs, specifically in the method you have chosen for adding a roof over a roof. Experienced contractors are more likely to provide reliable advice, efficient installation, and superior craftsmanship. They can also help you navigate any potential challenges or unexpected issues that may arise during the process.

License and Insurance

Ensure that the roofing contractor you choose is appropriately licensed and insured. Licensing ensures that the contractor has met the necessary requirements and possesses the necessary skills to perform the job. Insurance protects you and the contractor in the event of any accidents or damages that may occur during the project. Request proof of license and insurance before hiring any roofing contractor to ensure you are working with a reputable and reliable professional.

Customer Reviews and Recommendations

Reading customer reviews and seeking recommendations from friends, family, or neighbors can provide valuable insights into the quality of work and customer satisfaction of roofing contractors. Look for contractors with positive reviews and testimonials, as well as a solid reputation within the community. This will give you peace of mind knowing that the contractor you choose has a track record of delivering excellent services and customer satisfaction.


Adding a roof over a roof can offer numerous benefits, including increased durability, improved energy efficiency, and cost-effectiveness. It is important, however, to consider the potential drawbacks and factors specific to your situation before proceeding with this option. Evaluating the condition of the existing roof, conducting a structural analysis, and ensuring compliance with local building codes are crucial steps. Additionally, understanding the different methods of putting a roof over a roof and selecting the appropriate roofing materials based on climate, budget, and expected lifespan are key considerations. Regular maintenance, addressing potential issues promptly, and exploring alternative options such as roof replacement or repair are also important. Lastly, choosing a professional roofing contractor with experience, proper licenses, and insurance is essential for a successful roof over a roof project. By carefully weighing the pros and cons and making informed decisions, you can enjoy the benefits of a roof over a roof while ensuring the long-term safety and protection of your home.