Hi Rick,
That looks very nice. Why did you not provide a lower lip in addition to the upper lip? Even a relatively small lip will keep feces/urates and water spills out of the track.
Just curious, not a criticism or anything.
You could use heat tape on the floor but I would not use acrylic. Instead I would use expanded PVC (the boaphile material) available from sign shops.
If you're worried about burning I would spend a bit more cash and go with radiant heat panels rather than ceramic heat emitters. Helix seem to be the favorite RHP's of those that have used different types.
Whether the heat tape will be enough really depends on the temp of your room and the amount and placement of the venilation in the cages.
Hope this helps.
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I have four 40" x 24" x 16" (LxDxH) melamine enclosures I've built. I need to heat them for Ball Pythons. So one side has to be about 85-90 degrees. Will heat tape be enough inside the enclosure with a thin sheet of plexi over it and thermostat or will I need a ceramic bulb fixture mounted to the ceiling? If I use the ceramic bulb what should I use to cover it up so the BPs dont wrap around it?