Wood getting hot

Im currently in the process of building wooden vivariums for my corn snakes one is almost done and the other has been in service for about 2 months today I was dusting the top of the completed viv and getting ready to place the second wooden enclosure ontop of the first when I noticed that the wood directly over the heating element is warm to the touch not to hot to put your hand there for awhile but still noticeably warm. It your basic ceramic light fixture and 60 watt Ceramic heat bulb. Is this normal? Is this a fire hazard? How do I fix this? Any advice is appreciated