I had a small leak in a very tight place and I was on vacation, so looking for a quick fix to get me home I tried a can. It worked on a water pipe joint and is still holding but I sure wouldnt put it on a EPDM roof. There are plenty of good products to fix roof leaks with whether its a torn place or a seam. The seam can use the Crawling sealer used by automotive shops and it goes anywhere.