We have a small screened in porch (8 x 12) which we love using in the summer. We would like to use it as a 3 season room. Two sides of the porch are screened in, my plan is to use heavy vinyl fabric with snap stud screws. Has anyone done this? Should the snap stud screws be put on the outside or inside of the porch screen opennings? We plan to use at least 6 mil greenhouse UV treated vinyl or would it be better to use marine window vinyl (also UV treated). Thanks for any help.