Overlapping Sheets on Roof

Eric Olson
We are installing a complex steel roof using ProRib steel sheets (Menards), standard lengths are 36" nominal coverage, 9" on center rib spacing, .0142" thickness 29 gauge material, grade 80 steel and 16' long. Four of our sheets need to be 19' long to cover the distance with one sheet. Can you overlap sheets to make up the distance or are seams on a steel roof a big no-no? (If so, why, ice build up, water leakage, visual, etc) Can I use a 16" sheet and add three feet of scrap to make a 19' sheet? Custom lengths can be ordered, but with what I have on site and available, can I get away with overlapping the sheets? If I can overlap, I obviously need a support piece under the seams to screw to correct? How much overlap does there need to be 2", 6", 12"? Thank you for your time, Eric K. Olson Briarz Studio
Dick Bus
Brian, yes this product can be overlapped. You are correct the lap needs to be supported. Place two parallel rows of good Grade Silicone caulk or caulk tape 4" apart. With the first row 1" up from the edge you need a 6" overlap. Make sure the lap is the right direction to allow water flow. Use the longer panel along the bottom. I am assuming this is a roof with a minimum of a 4/12 pitch.

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