I have a deck made with treated materials, with a roof over it. It is a couple of years old and has been hosed many times cause I keep my Iguana cage out there in summer & hose it nearly daily then hose the porch. It is a great place for torts to stretch their legs but I don't want to injure their feet.
Patsy
Maybe you could knit some little tortoise booties!
Joking! I don't know anything about treated porches, but I bet you could even throw down some newspaper on dry days, if you were worried about it! Sounds nice for them!
If it is pressure treated, you would have to make sure there were no splinters. Pressure treated wood, I believe, has arsenic or something similar in it. That's why if you ever get a splinter from that stuff it is really irritating.