How do I tell the difference between a Pittsburgh seam and a snap-lock seam?

Pittsburgh Seam: Features a deep, open pocket on one edge and a single raw flange on the opposing edge. Once inserted, the remaining flap of metal must be manually hammered flat down the entire seam length to lock it. Used heavily in high/medium-pressure commercial systems. Snap-Lock Seam: Features a rolled female receptor pocket and a small barbed male edge. You simply push the male edge into the pocket until it audibly snaps together. It cannot be easily taken apart and is typically

[' Pittsburgh Seam: Features a deep, open pocket on one edge and a single raw flange on the opposing edge. Once inserted, the remaining flap of metal must be manually hammered flat down the entire seam length to lock it. Used heavily in high/medium-pressure commercial systems. Snap-Lock Seam: Features a rolled female receptor pocket and a small barbed male edge. You simply push the male edge into the pocket until it audibly snaps together. It cannot be easily taken apart and is typically used for low-pressure systems.']

Stop if

• Use this as training guidance. The foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, and AHJ/code requirements always control the final answer.

Steps

• Pittsburgh Seam: Features a deep, open pocket on one edge and a single raw flange on the opposing edge. Once inserted, the remaining flap of metal must be manually hammered flat down...

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