At first glance, adding a second layer of shingles to an existing roof might seem like a cost-effective and time-saving solution for homeowners in need of a new roof. However, this approach has several hidden drawbacks that can lead to long-term problems and additional expenses. In this blog post, we'll explore the reasons why homeowners should avoid double layering shingles.

Weight Concerns: Overburdening Your Roof's Structure

One of the most significant issues with double layering shingles is the additional weight it puts on your roof's structure. Roofs are designed to support a specific load, and adding a second layer of shingles can push the structure beyond its limits. This can lead to sagging, structural damage, or even a roof collapse in extreme cases.

Decreased Lifespan: Premature Aging and Wear

Double layering shingles can lead to a reduced lifespan for your new shingles. The extra layer traps heat, causing the new shingles to deteriorate more quickly due to increased thermal stress. This means you may need to replace the roof sooner than you would if you had removed the old shingles and installed a single layer.

Compromised Inspection and Repairs: Hidden Problems

A double layer of shingles makes it more challenging to detect and repair underlying issues, such as damaged decking or leaks. These problems can worsen over time, leading to costly damage and repairs that could have been avoided with a single layer of shingles.

Voided Warranty: Losing Manufacturer Protection

Many shingle manufacturers require proper installation, including removing the old layer of shingles, to maintain the warranty on their products. Double layering shingles may void the warranty, leaving you without protection if defects or premature failure occur.

Building Code Violations: Compliance Issues

In some areas, building codes prohibit double layering shingles due to the potential risks and structural concerns. By adding a second layer, you may be violating local regulations, which could lead to fines or forced removal of the additional layer.

Conclusion: The Risks Outweigh the Perceived Benefits

While double layering shingles might seem like an attractive shortcut, the long-term risks and potential costs far outweigh the initial savings. By removing the old shingles and installing a single layer, homeowners can enjoy a safer, longer-lasting, and more efficient roofing solution.