TPO (thermoplastic polyolefin) is a single-ply membrane used on flat and low-slope commercial roofs. It is popular in Austin because its white surface reflects much of the summer sun and its seams are heat-welded into one continuous sheet. Here is what a building owner should know before choosing it.
What Is TPO Roofing Made Of?
- Insulation boards over the roof deck, often tapered to steer water toward drains.
- Cover board in many systems, for a firm surface and better hail resistance.
- The TPO membrane, mechanically fastened or fully adhered.
- Heat-welded seams: overlapping sheets are fused with hot air so the seam becomes as strong as the sheet.
- Flashings around walls, curbs, drains and rooftop units, where most flat-roof leaks start.
Why It Suits Austin Buildings
- Heat. A white, reflective membrane keeps the roof surface cooler than a dark roof, easing the cooling load on the building below.
- Drainage. Ponding water shortens any flat roof's life, so tapered insulation and clear drains matter as much as the membrane.
- Repairs. Damaged areas can usually be patched by welding new TPO onto the existing sheet.
Choosing a Thickness
| Thickness | Where it fits |
|---|---|
| 45-mil | Budget projects and short planned ownership |
| 60-mil | The common choice for most commercial buildings |
| 80-mil | Long-term owners, heavy foot traffic, or extra puncture resistance |
Cost and Lifespan
TPO typically lasts 20 to 30 years with proper maintenance. Installed cost commonly runs $8 to $14 per square foot including insulation, depending on thickness, attachment method, tear-off and roof details. Regular checks of seams, drains and flashings are the cheapest way to reach the long end of that range. Our commercial roof cost calculator gives a starting estimate.
TPO or Something Else?
PVC holds up better where grease or chemicals reach the roof, such as above restaurant kitchens. Modified bitumen is a tough multi-layer option that some owners prefer for foot traffic. Silicone roof coatings can extend an aging roof that is still sound. The right choice depends on the building, so a site visit comes first.
Get a Commercial Roof Assessment
We provide free commercial roof inspections with photos and a written proposal within 24 to 48 hours. For independent background on low-slope roofing, see the National Roofing Contractors Association. Request a commercial roof inspection.
TPO Roofing FAQ
Sometimes. It depends on the condition of the existing roof and insulation, local code limits on roof layers and whether moisture is trapped below. A site inspection, sometimes with core samples, decides whether a recover or a full tear-off is right.
At least once a year and after major storms. Inspectors check the welded seams, drains, flashings and areas around rooftop equipment, where most flat-roof problems start.