Re: House fire
I'm in the midst of building my own frog room but don't have the luxury of working from the foundation up in my design. If I could have designed from the ground up, I would have taken advantage of many the suggestions above.
One thing that I would liked to have given more thought to was sufficient working surface. I use an old dresser but wish that I had more of space with access to a deep sink. I always seem to be running out of workable surface and have to put stuff on the ground only to pick it back up to use again later when I need it. Not the end of the world, but wish I had more clear horizontal surfaces to work with.
I may pick up a rolling cart to bring from tank to tank as I do maintenance to hold various things and streamline care. Hold my pruning scissors, rubbing alcohol, dusted flies, plant clippings, etc. Less trips back and forth, even in my modest room is a plus.
I'd also like to have a centralized hub where I can control everything from the lights to the misting schedule. Currently all my lights are plugged into timers in tough to reach locations. If I could build from the beginning the centralized hub would also have the thermostat for the room itself.
I'm sure you've already thought about this and others have mentioned it as well, but keep in mind your home may be someone else's home at some point. What you do now may be incredibly cool and functional for what you are trying to achieve, but keep in mind it's attractiveness to a future owner. You may never recoup the investment in your home's infrastructure, shoot you may be leaving money on the table when you do decide to sell.
I'm with everyone else, I hate buildins.
Just some things to think about.