A flat seam is best described as which statement?

• A. another name for a snap lock.
• B. formed in a rollformer.
• C. like a standing seam that has been bent flat.
• D. only used on flat pipe.

Answer: (C)

Think of a standing seam as a raised edge formed by bending the metal upward to create a vertical seam. If you take that same seam and bend it back down so it lies flat against the panel, you’ve created a flat seam. That’s why the description that a flat seam is like a standing seam that has been bent flat fits best. It’s not simply another name for a snap lock, nor a requirement that it be formed specifically in a rollformer, and it isn’t limited to use on flat pipe.