Ok so just to throw a wrench into your logic about indoor temps. I live in an old drafty mobile home and in the winter the other rooms get down into the low 50's on the coldest of nights. So again, and maybe we can get an answer, If I were to use ceramic heat emitters, what should I use? Or are night time heat lights better and if so what wattage? I know your all going to say it would be easier to keep the entire place warmer, that is not the case. I'm glad that one of the seniors questioned the other user about whether they had asked about night time temps at least. In addition to her question I have to add that we all do not live in regular new homes.
First- let me just restate- I let my chams drop down to about 50 all the time with no ill effects and have done so for many years (17 or so). This includes even baby chameleons. If it only drops into the low 50s in your home, personally I wouldn't worry about night heat. I probably would try to do something about the drafts though (foil or styrophome sheet insulation is fairly inexpensive and takes very little space and can be used to line the walls of a room, plastic window kits are sold to cover windows to eliminate drafts also). Of course I realize you are not me, and may want to warm things up a bit for your own peace of mind and that's fine.
If you want to use ceramic heat emitters- what exactly is your question about what you would need? I guess you are asking about wattage? You would probably need to experiment somewhat with your situation to determine the size wattage you would need to keep your temps up above 50. The problem as I see it with this idea is that your chameleon may not choose to fall asleep near the night heat source if day temps are warmer than night temps. And if that is the case, and then night temps drop, he probably isn't going to move in his sleep to a safe position. The other problem is if your home has drafts of 40 something degree air moving through the warm spot under the heat emitter where the chameleon is sleeping, that isn't going to be great for him. And then finally, if you have a number of enclosures, it may be cheaper to put a portable heater of some sort on a thermostat than it would be for you to put out 10 60 watt on all night ceramic heat emitters.
Here is what I do in my lizard building where there is no central heat source. I insulated the building really well so unless temps dip into the teens at night outside, no extra heat is necessary- temps remain above 50 during the night. When temps dip down into the teens outdoors, I plug a single 250 watt infrared heat spotlight in and hang it a couple of feet above the concrete floor in the center of the building, so that it heats the concrete. This is enough to warm the entire lizard building (42'x30') and keep it above 50 on the coldest nights. This is the kind of light sold at farm stores to keep baby animals warm on winter nights.
A smaller room (which is probably most rooms in a house) say in a trailer could probably be kept warm with far less- maybe a 150 watt infrared spot light hung in the middle of the room might do the trick (not over a cage- the idea is to warm the room, not provide a basking spot). Maybe even a 100 watt blacklight bulb hung in the middle of the room might do the trick. Maybe a small electric heater turned all the way down on low would do the trick as well.
In the end - there is no one size fits all answer when determining what you will need, unless you can locate someone on here with similar conditions (drafty mobile home, ambient temps just below 50 or whatever). Otherwise, my advice is just to experiment- but personally I feel it is better to keep your ambient night temps controlled, than it is to provide hot spots and count on the lizard being where it needs to be and avoid the risk of breathing cold air from drafts or worse- cold air breezes moving over a warm basking lizard that is sleeping, shocking it's system mildly. If it were me and I was set on using heat spots at night, I'd probably wrap my cages in plastic to keep the drafts out and the heat in... But I would much rather raise the ambient temperature in my room and eliminate sources of drafts. I realize that in some modern homes with the cavernous open floorplans around the living and dining areas, maybe that would be impossible without heating the whole home...
Did you ask what night winter temperature javsto is speaking of before making this proclamation?
