This how-to covers the process of properly sealing the roof edge with lap sealant. Video included.

Materials:
• (1) tube of Alpha Systems Non-sag Lap Sealant (I used ½ tube for 50+ feet)
• 1” blue tape
• Isopropyl alcohol
• Caulking gun
• Roof cleaning (i.e. Eternabond Roof Cleaner or isopropyl alcohol)
• Rag for cleaning
• Paper towels

Tips:
• Working with lap sealant is nothing like latex caulk or silicone, both of which can be easily shaped with a finger. Lap sealant is like marshmallow crème, very sticky and impossible to shape with a finger.
• Use a very thin bead on the non-sag sealant.
• Use a paper towel, and wet with alcohol to wipe the bead. Try to leave as little as possible on the tape but don’t wipe out the sealant application.
• Let it cure for a minimum of 24 hours, 48+ would be even better. I tried pulling the tape an hour after application and the sealant was sticking badly to the tape.
• After 24 hours the blue tape was falling off, which meant the lap sealant had cured enough to release the tape.
• It stuck in a few areas but not bad. A 48-hour cure would be better.
• Temperature may impact curing time, adjust accordingly.