TPO and PVC are the two most common white single-ply membrane systems on commercial flat roofs in Southern California. They look similar from the curb but behave differently on the roof. Picking between them depends less on price and more on what your building does.

What they have in common

Both are heat-welded white single-ply membranes that reflect heat, resist UV, and form strong seams when installed by a properly trained crew. Both can be fully adhered, mechanically attached, or ballasted depending on the project. Both are typically installed over a layer of insulation board on a commercial roof deck.

Where TPO usually wins

TPO is generally less expensive than PVC, and the membrane has improved significantly over the past 15 years. For warehouses, offices, retail strips, and multifamily buildings without unusual chemical exposure, TPO is often the practical choice. Membrane thickness matters: 60-mil is a common baseline, and 80-mil extends life on roofs with foot traffic or longer-warranty needs.

Where PVC is the right call

PVC handles chemical and grease exposure better than TPO. Restaurants, commercial kitchens, manufacturing facilities, and buildings with rooftop equipment that exhausts oils or solvents usually do better long-term with PVC. PVC seams also remain weldable later in the membrane's life, which simplifies future repairs. The premium over TPO is real but usually justified on the right building.

What both systems share at failure points

When a single-ply roof fails early, it almost always fails at the details: seams, penetrations, drains, parapet walls, HVAC curbs. The membrane itself rarely fails first. That means the installer's experience with flashing details and seam welding matters more than the brand of membrane.

Questions to ask before approving a single-ply scope

  • Has the installer been trained and certified by the manufacturer of the proposed system?
  • What membrane thickness is being specified, and why?
  • How are penetrations, curbs, and parapet walls flashed?
  • What is the manufacturer warranty path: labor, materials, or both?
  • What does the maintenance program look like to keep the warranty active?

When to call SunCraft

SunCraft is APOC certified and works regularly with both TPO and PVC systems across South Bay LA and Orange County. The free inspection documents the roof, identifies which system fits the building, and writes a scope that names the membrane, the thickness, and the warranty path. For commercial buildings considering a flat-roof reroof or replacement, that documentation is the right starting point.