TPO seam welding basics: heat, speed, and the probe test

A TPO seam is fused, not glued. Temperature, travel speed and pressure all work together, and each can change with the conditions on the roof.

Before a production run, weld two scrap pieces using the settings you plan to use. Let them cool, then peel them. Adjust and test again if the seam separates cleanly.

Roll the seam while it is hot, then probe both edges once it cools. A probe that catches tells you where to stop and correct the work before leaving the roof.