How to Install Metal Roofing Over Asphalt Shingles?

Are you considering installing a metal roof over your asphalt shingles? This can be a cost-effective and efficient way to upgrade your roofing system. This brief introduction will explore installing a metal roof over asphalt shingles. We will provide an overview of the steps involved in this method. Discover how metal roofing can transform your home and learn the essential guidelines for a successful installation over asphalt shingles. 

What are the Safety Precautions?

When installing metal roofing over existing asphalt shingles, it is essential to follow safety precautions to ensure a successful and safe installation. Here are some key safety measures to consider:

• Personal Protective Equipment (PPE)
• Fall Protection
• Roof Stability
• Secure Footing
• Electrical Hazards
• Proper Handling of Materials
• Tool Safety
• Weather Conditions
• Professional Assistance

Adhering to these safety precautions can minimize the risk of accidents, injuries, and damage while installing metal roofing over asphalt shingles. Prioritize your safety and the safety of others throughout the entire process.

Step-by-Step Guide on How to Install Metal Roofing Over Asphalt Shingles

Installing metal roofing over existing asphalt shingles can be a viable option, as it saves time and reduces the need for a complete tear-off of the old roof. Here is a step-by-step guide on how to install metal roofing over asphalt shingles:

• Prepare the Roof: Inspect the existing asphalt shingles for damage or deterioration. Ensure that the roof deck is in good condition and can support the additional weight of the metal roofing. Repair any damaged or rotting sections and replace any loose or missing shingles.
• Install Furring Strips: If the existing shingles create an uneven surface, install horizontal furring strips over the roof deck. These strips provide a level and solid base for the metal roofing panels. Space the furring strips according to the manufacturer’s recommendations, typically between 16 to 24 inches apart.
• Measure and Cut the Metal Panels: Measure the roof length from eave to ridge, accounting for overhang. Use metal-cutting tools such as snips or a circular saw with a metal-cutting blade to cut the metal panels to the required size.
• Install Underlayment: Lay a high-quality synthetic underlayment over the entire roof surface, ensuring it overlaps appropriately and is secured with roofing nails or staples. The underlayment provides an additional layer of protection against water infiltration.
• Start with the Eave Edge: Begin installing the metal panels at the roof’s eave edge. Align the first panel with the roof’s edge and secure it using screws or nails. Use roofing-specific fasteners recommended by the manufacturer to ensure proper attachment.
• Continue Installing Panels: Place the subsequent panels horizontally, overlapping each panel by the manufacturer’s recommended amount. Fasten each panel securely, ensuring the screws or nails penetrate beneath furring strips or the roof deck.
• Trim and Fit Panels: As you reach roof edges, valleys, and other obstructions, trim the metal panels to fit correctly. Use appropriate cutting tools and techniques to achieve accurate measurements and clean cuts.
• Install Flashing and Accessories: Install metal flashing at the roof edges, valleys, chimneys, vents, and other areas where additional waterproofing is required. Secure the flashing and seal any gaps or joints using appropriate sealants.
• Complete with Ridge Cap: Install the ridge cap at the roof’s peak to provide a finished look and seal the ridge against water penetration. Use screws or nails to secure the ridge cap, ensuring it overlaps the metal panels on both sides.
• Inspect and Clean: Once the installation is complete, thoroughly inspect the roof for any loose fasteners, damaged panels, or areas that require additional attention. Clean up any debris or metal shavings from the installation process.

Professional Vs. DIY Installation 

It is important to note that the above steps are a general guide, and it’s recommended to follow the specific instructions provided by your metal roofing system manufacturer. Additionally, local building codes and regulations should be followed throughout the installation.

Installing metal roofing over asphalt shingles can be done by hiring a professional roofing contractor or as a do-it-yourself (DIY) project. Let’s examine the pros of each approach:

Professional Installation

• Expertise and Experience: Professional roofing contractors have extensive knowledge and experience installing metal roofing systems. They know industry best practices, safety protocols, and local building codes.
• Quality Workmanship: Professionals have the necessary skills and tools to ensure a precise and high-quality installation. They can handle complex roof configurations, flashing details, and other challenging aspects of the project.
• Warranty Coverage: Reputable roofing contractors often provide warranties on their workmanship, which can offer peace of mind and protection against potential issues in the future.
• Time and Convenience: Hiring professionals saves effort and time since they will take care of the entire installation process, from preparation to clean-up. You can focus on other tasks while the experts handle your roofing project.

DIY Installation

• Cost Savings: DIY installation can save money on labor costs, as you won’t have to pay for professional services. However, it’s essential to consider the potential risks and challenges involved in the DIY approach.
• Sense of Accomplishment: Completing a DIY project can be fulfilling and provide a sense of accomplishment. It allows you to take pride in your work on your property.
• Flexibility and Control: With a DIY installation, you have more control over the timeline, materials used, and the overall process. You can tailor the project to your preferences and make adjustments as needed.

However, it’s crucial to consider the following factors before opting for a DIY installation:

• Skill and Knowledge: Installing metal roofing requires specific skills and knowledge of roofing systems. Improper installation can lead to leaks, poor performance, and voiding of manufacturer warranties.
• Safety Risks: Working at heights and handling heavy materials can pose safety risks. Without proper safety measures and equipment, DIY installations may result in accidents or injuries.
• Time and Effort: Installing metal roofing is a labor-intensive process that requires attention to detail and careful execution. It can be time-consuming, especially if you need more experience or assistance.

Before deciding on DIY installation, evaluate your level of expertise, available time, and comfort with complex construction projects. If you need clarification on any aspect of the installation process, it’s recommended to consult a professional roofing contractor to ensure a successful and safe installation.