Learn when single-ply roofing can go over an existing flat roof in Georgia. Find out what building codes require and how to know if your roof qualifies.

Can you install single ply roofing over an old roof?

Single Ply Roofing FAQs
October 31, 2025•3 min read

Can You Install Single-Ply Roofing Over an Old Roof?

Can you install single-ply roofing over an old roof?
Yes, in many cases, you can install a single-ply membrane (like TPO, EPDM, or PVC) over an existing flat roof. But it’s not automatic—you need a professional roof inspection first.

Here’s what a contractor like Roof Nuts will check:

  • Moisture in the old roof: Any trapped moisture needs to be removed. A wet substrate can lead to membrane failure.

  • Structural soundness: The roof must be able to support the new material without sagging or deflection.

  • Drainage and slope: The roof must drain properly. If water is ponding, it may need to be re-sloped using tapered insulation.

  • Building code compliance: Georgia building codes and manufacturer specs must allow for a roof-over application.

  • Number of roof layers: Most codes only allow two layers of roofing. If you already have two, a full tear-off may be required.

If all conditions are met, a roof-over can save time and money by avoiding tear-off labor and disposal costs.

What Is Single-Ply Roofing?

Single-ply roofing is a flexible, waterproof membrane commonly used on flat or low-slope commercial roofs. Common types include:

  • TPO (Thermoplastic Polyolefin)

  • EPDM (Ethylene Propylene Diene Monomer)

  • PVC (Polyvinyl Chloride)

These materials are typically installed fully adhered, mechanically fastened, or ballasted depending on roof conditions and manufacturer instructions.

How do I know if my roof qualifies for a roof-over?

The only way to know for sure is to have your roof inspected by a licensed roofing contractor. In Georgia, factors like high humidity, frequent storms, and sun exposure make inspections even more important.

Benefits of Installing Single-Ply Over an Existing Roof

  • Lower labor costs (no tear-off)

  • Reduced landfill waste

  • Faster installation

  • Less disruption to building operations

When is a tear-off required instead?

You’ll likely need a full tear-off if:

  • The existing roof is saturated with moisture

  • The current roof is damaged or unstable

  • You already have two roof layers

  • The slope doesn’t meet minimum drainage standards

  • The roof deck is deteriorated or corroded

Frequently Asked Questions

How many roof layers are allowed in Georgia?
Most local building codes follow the IBC and limit commercial roofs to two total layers. Anything beyond that requires tear-off.

Is single-ply roofing good for Georgia’s climate?
Yes. TPO and PVC resist UV rays, heat, and humidity—making them well-suited for hot, storm-prone areas like Atlanta, Savannah, and Macon.

How long does single-ply roofing last?
With proper installation and maintenance, single-ply membranes can last 20 to 30 years depending on the product and exposure.

Serving Cities Across Georgia

At Roof Nuts, we install and inspect single-ply roofing systems across Georgia, including:

  • Atlanta

  • Augusta

  • Columbus

  • Macon

  • Savannah

  • Athens

  • Sandy Springs

  • Roswell

  • Johns Creek

  • Warner Robins

Get a Professional Roof Inspection

Before deciding to install single-ply over your old roof, schedule a free inspection with Roof Nuts. We’ll check moisture levels, structural soundness, and code compliance—so you don’t make a costly mistake.

📞 Call 404-476-6851
🌐 Visit RoofNutsGA.com

Let’s make sure your new roof is installed right—the first time.

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