As others have said, you don't
need to fiberglass it. But you can, if you want to.
You can fiberglass without compression material, but you will use more resin, and thus add more weight. That can be alleviated by vaccuum bagging (which requires a lot of equipment investment), or using shrink tape (you can shrink it with a heat gun, if you don't have an oven, though it's time consuming and you won't get as much compression.).
If you go the shrink tape route,
don't use West Systems Epoxy, especially if you use a curing oven -- shrink tape requires a temperature somewhere in the 150 - 160 range to begin to shrink, and West Systems Epoxy begins to break down if exposed to 120F for very long.
No matter what you do, if you're going to apply heat, be aware of the affects of temperature on the epoxy you're using, and what its limits are. Some epoxies don't like to go above about 180F, and with shrink tape, you get maximum compression at around 180 - 190F.
You
can do "poor man's shrink tape" using basket wrap from a craft store with a hair dryer. Just apply wax to the basket wrap before you put it over the epoxy, or you'll never get it off. Been there, done that, have the Merit Badge.
-Kevin