This mechanical seam connects adjacent metal roof panels by folding their upright edges over each other a full 180 degrees, creating a double fold. The interlocking profile provides superior wind uplift resistance and watertightness compared to single-lock seams. It requires a mechanical seamer to finish the joint on the roof deck.
Heard on the job
Run the mechanical seamer up that ridge one more time to make sure we've a true double lock standing seam.