Well, I just finished cleaning burm cages (puuueeeeeee!!!) so my first thought goes to the flooring and splash/smear area of the lower walls.
Concrete basement floors stay fairly cool year-round. Ideally, an insulated plywood subfloor would be best. Jeremy (bighurt) or Chris Harper has either done one or had good plans for one. I remember one of them talking about it here awhile back.
Other than that I think your best options are either painting the concrete floor or using vinyl. I think a patternless sheet vinyl would be your best bet (other than the subfloor). I say patternless because the ones with patterns have indentations that will make it harder to clean.
Since vinyl comes in 12ft widths you could just get the length you need (5ft or so) for the floor. An additional 2ft of vinyl (12 x 7) should give you enough to go 1ft up each wall. They make a plastic or vinyl rubber cap that can be used to cap off the top, bare edge for a cleaner, better look. You'll have to get that from a floorcovering store, but it's inexpensive.
For insulation, I'd probably use insulation boards for the concrete (exterior) walls, probably one of the ones with foil backing. For the 11.5 wall that you're gonna have to build by anchoring it to the concrete floor I'd use the thick, heavy rated rolls and maybe even refletix.
I'd slap a few picture windows in there. I'm kinda hung up on door placement. Just about every walk-in cage I've seen failed to start out with safety concern. What I mean is, you don't want the door in an area where your snake may be sleeping. I believe I'd put it on one end or the other and make the inside of the cage in that area an unlikely place for the snake to rest, if there's such a thing. Ha!
Is this anything close to what you had in mind? Close to the type of suggestions you're lookin' for?
Catch ya later!
HH
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Due to political correctness run amuck,
this ol' hillbilly is now referred to as an:
Appalachian American