Rod - Do you plan an air gap between the layers? What heating do you plan to use? I'm pretty sure heatmats need some air circulation underneath. If you plan to fit heatlights into each viv, then that's probably not a concern. You would need to have them on separate stats though because the heat from the lower light will warm the floor of the viv above - probably not a bad thing.

Mike - Home - www.crazyreptiles.eu