Ryan,
Home Depot sells an aluminum screen that is coated with vinyl which is great for outdoor enclosures. Of course, this is more expensive than the regular old window screen but it lasts longer. Depending on where you live, plain old fiberglass coated with vinyl might work, keep in mind that it will not protect the chams against intruders as well as aluminum will.
Home depot sells a "PET SCREEN" that is nothing more than fiberglass screen coated with heavy PVC, I'd stay away from this. Outdoor cages should protect the chams as well as provide them ample wandering space in the sun. If you use wood as the framing, make sure you use a coating on the wood to keep it from rotting from all the mistings you will do on the chams.
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Raf
1.0 Jacksons baby (Frankie)
1.1 Nosy Be's (Mars and Roja)
1.3 Bearded Dragons (Diego, Ginger, Baby and Georgia)
1.1 Adult Sulcattas (POOPIE and George)
0.0.2 Baby Sulcattas (frick and frack)
1.0 Home's Hingeback Tortoise (SPEEDY)
0.0.2 Red ear slider babies (Hingis, Dingis)
1.0 Yellow Footed Tortoise (Alfred)
1.1 3 toed turtles
1.0 Red Siberian Husky (Harley)
0.1 English Bulldog (Alice)
0.1 Blue Merle Great Dane (Wednesday)
Saltwater Fish and Inverts too