If you are using heat lamps, I assume that you have a glass tank setup.
For Glass, I suggest the following (it worked for me):
I used a Ceramic heating element on top for the ambient temp -- it had its own thermostat. I set this to 84 and I had the probe mounted to the glass about 3 inches above the substrate. This made the bottom of the enclosure about 80.5. Then I added two small repti pads to the bottom to provide a warm area and put them on their own thermostat.
So for your environment: if you connect both of your existing heat lamps to one thermostat and regulate it for the cool/ambient temps, you would only need to get a UTH and thermostat for the hot spot.
That way the temp would stay the same no matter if the room was cold or warm.
Also -- just a note on the human body, it is not very good to cool your environment below 68 degrees. It takes a lot of calories to heat your own body to 98.6 -- we are warm blooded and need that temp for everyting to function ok -- and it costs a bunch to run an air conditioner so if you set it to 68-70 you should be comfortable. Actually, I have my a/c set to 74 -- that is cool enough for me and my family.
