Find out why insulation is essential for single ply roofing systems in Georgia. Learn the benefits, best materials, and installation tips from Roof Nuts.

Do single ply roofs need insulation?

Single Ply Roofing FAQs
November 12, 2025•2 min read

Do Single Ply Roofs Need Insulation? (Georgia Homeowner’s Guide)

Yes, insulation is a critical part of any single ply roofing system.

Whether you’re installing TPO, PVC, or EPDM, insulation is not optional—it directly affects your roof’s energy efficiency, durability, and moisture control.

Here’s why insulation matters for single ply roofing:

1. Improves Energy Efficiency

  • Insulation reduces heat transfer through your roof.

  • Keeps your building cooler in summer and warmer in winter.

  • Helps meet Georgia's energy codes and lowers utility bills.

2. Prevents Condensation Problems

  • Without insulation, warm interior air can meet the cold roof deck and cause condensation.

  • This leads to mold, mildew, and potential damage to the roof system.

  • Proper insulation helps maintain a stable temperature and prevent moisture buildup.

3. Supports Code Compliance

  • The 2021 International Building Code (IBC) and International Energy Conservation Code (IECC) require commercial and low-slope roofs to meet minimum R-value targets.

  • In Georgia, polyisocyanurate (polyiso) is the go-to insulation board due to its high R-value per inch.

4. Reduces Thermal Bridging

  • Insulation should be installed in multiple layers with staggered joints.

  • This reduces heat loss at the seams and fastener points—also known as thermal bridging.

  • Layering improves overall performance and extends roof lifespan.

5. Boosts Roof Performance

  • Insulation provides support to the membrane and improves resistance to foot traffic, hail, and other physical damage.

  • A well-insulated system performs better under Georgia’s heat, humidity, and storm conditions.

Recommended: Polyiso Boards

  • Why polyiso? It offers one of the highest R-values per inch and is compatible with most single ply membranes.

  • Installation tip: Use multiple staggered layers to reduce gaps and air leaks.

FAQs

How much insulation do I need for a single ply roof?

In Georgia, commercial buildings typically need a minimum of R-20 for roof assemblies. Always check local codes and energy requirements.

Can I install single ply roofing directly on the roof deck without insulation?

Not recommended. It may cause condensation, reduce energy efficiency, and fail building inspections.

What’s the best insulation for flat commercial roofs in Georgia?

Polyiso is the most popular choice due to its R-value, availability, and compatibility with TPO and PVC systems.

Need Help with Your Flat Roof in Georgia?

At Roof Nuts, we design and install energy-efficient single ply roofing systems for businesses and homeowners across Georgia—from Atlanta to Augusta, Macon to Savannah.

Want expert advice on insulating your roof?

Call us today at 404-476-6851 or visit RoofNutsGA.com to request a free inspection.

Back to Blog