I have a wooden viv for my bp. And I do have a low wattage lamp to keep the ambient and cooler temps where they should be. It is not inside, but sat on top in a recess with mesh type material( already built in viv and safe for heatlamps) for the hotspot I have a uth, with thermostat to regulate it, but as you know it's no use under the wooden base, unsafe etc. So it is inside the viv, before you all gasp, it is safely installed, taped to a glass casing designed for this. (Amazon sell the casings).
Kath.