Is It Okay To Put A New Roof Over An Old One?

When it comes to replacing your roof, some companies may suggest installing new shingles or adding other roofing materials over the existing ones. This approach, known as a "roof overlay" or "layover," can be problematic for several reasons.

First, without removing the old materials, there is no way to thoroughly inspect the roof deck, potentially hiding or creating underlying issues. Additionally, if a leak develops, tracking it can be more difficult and complex with multiple layers, often leading to failed repair attempts. It’s also challenging to address ventilation issues without removing the old roof.

Furthermore, overlaying a roof typically does not include replacing accessories or flashings, which have limited lifespans. As a result, the new roofing material may have a shorter lifespan due to increased environmental stress and inadequate ventilation.

Putting a new roof over an old one can also negatively impact your home's value and appearance. In regions like the Pacific Northwest, a layover can decrease your property's value, negating any upfront savings from this cost-cutting measure. 

While putting a new roof over an old one might seem like a convenient and cost-effective solution, it often leads to more problems down the line. The inability to properly inspect the roof deck, the challenges in managing ventilation, and the shortened lifespan of roofing materials all make this approach less desirable.

At Valentine Roofing, we believe in doing the job right the first time, which is why we always perform a complete tear-off and roof replacement. This ensures that your new roof is built on solid plywood, free of hidden issues, and new materials that provide optimal performance and longevity. Investing in a full roof replacement may involve a higher upfront cost, but it provides a more durable, attractive, and valuable roof for your home. Call Valentine Roofing at (206) 766-3464 for a fast and free roof replacement estimate today!