I had a cigarette burn a hole in a tramp (imagine how pissed I was, especially since I don't smoke). Anyway, it was pencil-sized (in diameter). This was on a Hobie 16 mesh tramp.

I never fixed it, it never got bigger. Depending on how the hole got there, and whether it's in a stressed part of the tramp, you might not need to worry at all.

Mike