Can You Put New Shingles Over Old Shingles

Installing new roof shingles is a significant project. Homeowners often wonder if they can place new shingles over old shingles, which is a good question. The answer to this question cannot be a straightforward ‘yes’ or ‘no,’ as certain factors determine the possibility of shingling over existing shingles. In this article, we will discuss the advantages and disadvantages of shingling over existing shingles and the benefits of a complete tear-off and replacement. We will also provide an overview of local building codes and roof condition considerations homeowners should keep in mind.

So, can you put new shingles over old shingles? The answer is yes; it is possible to install new shingles on top of existing ones. But, specific conditions must be met, and several considerations must be taken into account. First, it is essential to understand your local building codes. Most jurisdictions won’t allow more than two layers of roofing on a home, and if the house already has two layers, a complete tear-off is in order. If it has only one existing layer, the roof may be a candidate for a second layer. The condition of the existing roof will also help determine if a shingle-over-shingle installation is possible. If shingles are weathered, warped, or curling, they aren’t suitable to be shingled over. New shingles require a smooth surface for proper installation and performance. Homeowners should also consider whether the roof needs replacing due to extensive leaking. In this case, putting new shingles over the existing ones may not be wise, as water damage to the deck, or mold issues might be left untreated if they remain hidden under the existing roof.

While the idea of shingling over existing shingles may be appealing to homeowners due to lower costs and faster installation time, it’s important to understand the potential risks. For instance, contractors may need to explain that a roofing system is composed of many parts that work together to provide protection for their home. Many homeowners think of a roof as only what they can visibly see—the shingles. However, a roof’s peak performance requires each layer of the roofing system to work correctly. GAF brochures can help with educating homeowners. For example, the GAF Timberline HDZ® brochure has diagrams that identify each layer of the roofing system, which can help homeowners understand how each layer is necessary to achieve a roof’s peak performance.

Homeowners must also consider the benefits of a complete tear-off and replacement. A tear-off allows the contractor to inspect the wood deck’s condition and determine if repairs or new OSB board are needed to ensure it’s structurally sound. Tearing off the roof’s old layers can help ensure the new system has a solid, smooth surface for optimal performance. A total replacement also allows an adequate leak barrier to be installed in critical areas, including rakes, eaves, valleys, hips, and around penetrations.

In conclusion, when it comes to installing new shingles, homeowners must consider several factors that determine whether shingling over existing shingles is possible. While it may be tempting to shingle over existing shingles due to lower costs and faster installation times, homeowners should consider the potential risks. A total replacement offers numerous benefits, including a thorough inspection of the wood deck’s condition and the installation of an adequate leak barrier in critical areas. If you’re considering installing new shingles, contact Exterior Home Solutions LLC, located in Richmond VA, for residential roofing services. Our team of experts will help you determine the best option for your home.