TPO vs PVC Roofing Systems
What is the difference?

As TPO and PVC are both thermoplastics, the two materials have some overlapping characteristics. However, there are distinct differences in their composition and more particular properties.

Overview of TPO Roofing and PVC Roofing

TPO roofing membranes consist of an ethylene or polyethylene thermoplastic bound to ethylene propylene rubber. PVC roofing membranes are made by polymerizing vinyl chloride monomers, then adding plasticizers to increase flexibility.

Although TPO was originally designed to be a superior alternative to PVC, it’s difficult to definitively say which is the optimal roofing solution. Both membrane materials offer—among other advantageous material characteristics—resistance to chemicals, grease, oils, and punctures to varying degrees. Deciding which of the two materials best suits a particular roofing application requires a more detailed look at their properties.

PROS AND CONS OF TPO

While PVC offers better resistance to puncture and weathering, TPO (like PVC) is recyclable and environmentally friendly. Its reflective surface reduces UV radiation and helps with energy efficiency.However, TPO is also less resistant to chemicals than PVC, so it is not the optimal choice where grease or harsh chemicals are involved. It may also be more difficult to install due to its stiffness. Additionally, as the popularity of the material is relatively new, some manufacturers may use subpar formulations that demonstrate a higher risk of membrane cracking.

PROS AND CONS OF PVC

PVC has been a mainstay in construction for over 30 years, and its reputation for durability is well-deserved. PVC is highly resistant to chemical damage and somewhat resistant to punctures or weathering. It also tends to be more flexible and easier to install due to the addition of plasticizers in its formulation.

However, the use of plasticizers does raise some concerns regarding weathering. Some plasticizers used in PVC break down more quickly than the rest of the material, increasing the rate of degradation. Additionally, the high durability of the material also results in generally higher material costs and environmental impact.

Considerations When Choosing TPO or PVC Roofing

The similarities between PVC and TPO make either material a likely option for most flat roofing projects. When deciding between the two materials, there are a few considerations that can help determine which is best suited for the project, such as:

• TPO is cheaper than PVC per square foot of material. However, the amount of labor during installation is about equal for both materials, if not slightly more intensive for TPO.
• PVC can be easier to install due to its greater flexibility. Additionally, some TPO installations may require more work if the contractor decides to use glued seams over welded seams.

Industry standards

Due to the relatively regular updates to ASTM standards for TPO, some manufacturers may not follow the most recent standards. The same risk is much lower for established materials, such as PVC.