Cover a damaged roof until it's repaired. Heavy-duty vinyl holds up for months through storm season; 12 mil poly is a quick patch for a few weeks. Size it at the damaged area plus 2 ft on every side, and run it over the ridge if you can.
Choose it if the roofer is weeks or months away, it's storm season, or you'll reuse the tarp.
Choose it if the repair is days or a few weeks away and the tarp won't be reused.
Not sure how long? Buy vinyl. Replacing a failed poly tarp in the middle of a storm costs more than doing it once. Size it to the damage plus about 2 ft on every side, and over the ridge if you can.
