I am looking for some advice for my porch. Currently It has many ripped screens and an astroturf floor. What I am thinking of doing is the following:

ripping up the carpet and putting a new floor down. Should i use TG, plywood, or something else? ( Currently underneath astroturf is plywood)

Secondly I want to finish the bottom maybe 3ft with TG to give it a more finished room appearance. Is there a reason why I should not do that?

All in all I want to make it appear as much finished room that will still hold up to the elements as I live in New Jersey so ou weather runs the gamut.

Thanks for the help