I live in California, in the Bay Area. My townhouse doens't have central AC, so that won't be an issue. The issue is I never use the heater, not for me, but for possibly housing snakes. I like it 65ish and in the summer I use a window AC to keep my room near there so I can sleep at night.

In the winter it can get to the low 60's. I have a spare bedroom that I am planning on putting a rack in. I can put a room heater in there to heat the entire room but I am considering another option and am wondering if it is viable.

In most racks a strip of 3" flex watt tape is used in the back to create a hot spot. Could I add a second strip, controlled by a second thermostat or Herpstat II, in the front to maintain the temp there? Should I use 4" or 11" instead since the room temperature will vary so much? Maybe an 11" in the back because a 20watt might be able to react quicker and a 3" or 4" in the front?

Is it a reliable concept to think that a rack could exist sustainably against the elements? If yes, is there anything else I should be considering? I will use a proportional thermostat.

The rack itself is under consideration. I looked about 4 years back on these forums for ideas. There are some good ones. I am contemplating some other things as well.