belly heat VS rear wall heat

which do you prefer? im looking at a rack that has rear wall heat and i was always told belly heat is better, but never WHY. does it really MATTER? is rear heat just as good? i would think belly heat is better as (duh!) heat rises, so rear heat isnt really going INTO the bin, just UP..... am i right? should I insist the maker install belly heat not rear heat? thanks

I've built racks using both heating methods. Overall belly heat is more versatile and more effecient.
In my experience the back heated racks would only work in my heated snake room. Even then the heat tape had to run at full power to maintain the proper temperature. I prefer needing a thermostat to keep the heat from getting too high, then if you need a little more, you have it. The heat loss is much greater with back heat, however if a solid back were used this would be decreased.

Another issue with back heat is I would only use it for hatchlings and young snakes. The actual warm area is significantly smaller using back heat because you are heating the vertical rear wall rather than an area of the floor. The snake gets primarily radiant heat coming off that wall and therefore can only warm one side at a time so to speak as opposed to full body warming of heat from underneath.
With a hatchling, the body mass is such that this works fine, but with larger adults I believe more effecient digestion will be seen with more complete access to the warmth.

The only real benefit of rear heat to the user is the heat tape is not exposed to the wear of the tub sliding across it. There are ways to minimize that though.
From the builders perspective rear heat is easier to install due to how it's wired, but if the results are not as good then that's not a reason to do it.
I initially tried rear heat on a couple of hatchling racks after seeing some of the bigger cage manufacturers using that method. It works ok for that application in my herp room, but I will not be building or using any racks in the furure that are heated from the rear. In fact I recently moved the entire room and took that opportunity to rewire one of me larger racks to use under box heating instead.

If it were me and I was buying a rack I would require belly heat regardless of the tub size.

I think that's about right. Some heat will radiate in, when you have a back or side panel, but I don't think that method is very efficient.

Thanks. Guess I wont be buying from these people then, they say they cant put the belly heat in on this particular rack, and the other size rack (that they can) is out of my pricerange right now. grrrrr

That's what I should have said, Clay. . Sometimes I forget that not all of us have learned the same things, and it wouldn't hurt to spell it all out. Guess that's why one of my nicknames is Silent John.

and came to the conclusion that the animals prefer the Belly heat.. When i had back heat the animals never moved from that area, as if they could not get warm enough, now with all my racks with belly heat, they move around to adjust to their own comfort zone, and eat alot better also!!! Good Luck! Mike L.

Originally Posted by amayon

i would think belly heat is better as (duh!) heat rises...

Heat does not rise, heated AIR rises, and the typical heat source used in a rack does not heat the air much at all. So the effieciency of belly heat has little to do with heat rising and more to do with other issues of thermodynamics.

For most rack situations I would prefer belly heat but there are exceptions. I won't get into that right now. I'm only on a few hours sleep and I don't have much time at the moment.

I will say that with the proper use of a reflective insulation you can greatly increase the efficiency of back heat. The last sweater-box rack I built was heated with nothing more than a single strip of rope-light along the back of each tub. The back of the tub was wrapped with Reflectix insulation and I was able to raise the temperature of the tub by 5*F. That was without even taping down the Reflectix to close off the large gaps on the back of the rack.

Another example:

I recommended to a guy that he cover the back of a rack with Reflectix. He was having trouble acheiving the temps he wanted. He just loosely placed the Reflectix over the back and started to do some other work. Within 20 minutes all of his snakes were pinned at the front of the cage, some even submerged in their water bowls. The rack has actually become TOO hot. He was only using a rheostat so the rack went from being borderline cool to borderline hot with the same wattage supply.

Reflective insulation is why radiant heat panels are so efficient and work well when on the ceiling of a cage. Remember, you can use RHP's to heat homes with 8' or taller ceilings. Also, depending on the flooring material, the floor temperature will actually be warmer than the ceiling, provided you're not measuring the surface temperature of the RHP itself.

This works because radiant heat (which is what Flexwatt produces) does not rise like convective heat. It travels parallel from its source until it is absorbed or reflected.

I believe Matt (the forum sponsor) sells Reflectix in small quantity for those of you who don't want to buy an entire roll.

Would aluminum foil work as a reflector?

Originally Posted by Chris_Harper2

Reflective insulation is why radiant heat panels are so efficient and work well when on the ceiling of a cage. Remember, you can use RHP's to heat homes with 8' or taller ceilings. Also, depending on the flooring material, the floor temperature will actually be warmer than the ceiling, provided you're not measuring the surface temperature of the RHP itself.

This works because radiant heat (which is what Flexwatt produces) does not rise like convective heat. It travels parallel from its source until it is absorbed or reflected.

I believe Matt (the forum sponsor) sells Reflectix in small quantity for those of you who don't want to buy an entire roll.

Can this product be used between a UTH and the underlying surface to reflect more of the heat upward and into the cage?

Or is it intended more to wrap the walls with to retain what heat is inside inside?

I know that some heat mat manufacturers say that you can add insulation under their mats. My concern is for the safety of doing this. Heat build up and all.