Can You Install a Metal Roof Over Existing Shingles?

If you're thinking about replacing your old asphalt roof with a metal one, you might be wondering if you can just install the new roof over your existing shingles. The short answer is yes, you can. 

In the roofing industry, this practice is referred to as an “overlay” or “roof-over.” But just because it’s possible doesn’t always mean it’s the right move for your Pennsylvania home. 

To help you decide if it is a smart decision for you, let’s take a look at some of the pros and cons of this approach.

The Benefits of Installing a Metal Roof Over Asphalt Shingles

As you might expect, there are many benefits to installing a new metal roof over existing asphalt shingles, including:

Cost Savings

By skipping the tear-off, you can cut back significantly on labor and waste disposal costs. Fewer labor hours and no dumpster fees can make a noticeable difference in the total project budget - something every Pennsylvania homeowner appreciates when managing expenses.

Quicker Turnaround Time

Overlay installations usually move faster because the crew doesn’t have to remove the old roof. This can be particularly helpful if you’re trying to schedule around heavy rain or snow.

Extra Insulation and Noise Control

Keeping the old shingles underneath the metal roof adds a buffer that can help with insulation and sound dampening. This can lead to more stable indoor temperatures and a quieter living space.

Less Mess and Disruption

Without a full tear-off, there’s less debris, less dust, and less noise. It’s a cleaner, quieter process that’s easier on both you and your neighbors.

The Drawbacks of Installing a Metal Roof Over Asphalt Shingles

Of course, there are also some drawbacks to installing a metal roof directly over an old asphalt roof. While it’s allowed by code in most of Pennsylvania, it’s not always the best choice. 

Consider the following:

Risk of Hidden Damage

Installing metal over worn shingles can hide problems like rot, mold, or water damage. Without pulling up the old roof, these issues can go unnoticed and worsen over time.

Structural Load Concerns

Even though metal is relatively lightweight, you’re still layering one roof over another. On older homes or structures that have been reroofed before, the added weight could be too much.

Surface Irregularities Can Transfer

Any bumps, dips, or warping in the old shingles can telegraph through the metal panels. This can affect both aesthetics and long-term performance - particularly here in PA, where ice and snow buildup is common.

Resale Considerations

Future buyers might view a roof-over installation as a shortcut rather than a long-term solution. That could affect resale value or lead to additional questions during inspections.

Need Advice from Experienced Pennsylvania Roofers?

Still not sure if installing a metal roof over your existing shingles is the right move? Contact the team here at Solarshield. Our skilled Pennsylvania roofers will come to your property, evaluate your current roof, and help you decide what makes the most sense for your situation. We’ll give you a free, no-pressure quote and honest guidance - so you can move forward with confidence.