My preferred method with heat tape is to cut out a rectangle about 2" longer and wider than the size of tape needed. Don't cut this rectangle all the way to side so the bottom remains one piece for structure.
Then cover the entire floor with expanded PVC, aka Sintra, available at sign shops.
The tape can be attached underneath with foil tape. Grooves can be routed for the cords to run out the back.
Another option, and one I like even better, is to not have a melamine floor at all and simply staple 1/4" Sintra directly to the bottom of the cage. Works very well when you're stacking it on top of another cage anyways. But if you're not comfortable with your ability to build a strong cage without a wooden floor then the cutout method is fine.
In my opinion these methods improve the cage(s) in every way except for cost. You'll probably make your money back over time with heating efficiency vs. trying to heat through melamine.
This method makes the cage...
1) Lighter
2) Easier to clean where snake cages need it most - the floor
3) Makes for a durable yet easy to replace floor.
4) Provides air space for the heat tape (when using the floor cutout).
5) Increased thermal mass - important with heat tape
6) A more natural heat gradient is achieved due to the conductive nature of Sintra.
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Current snakes:
0.2 Gonyosoma oxycephala - (Silver/Yellow)
3.3 Gonyosoma oxycephala - (Green)
2.1 Gonyosoma janseni - (Black)
3.3 Gonyosoma janseni - (Black & Tan)
