Hello, my wife and I just bought a home that is about 112 years old. We have a ton of remodeling projects to do. We have decided to start in our office. After removing some built in cabinets I have unearthed tongue and groove walls covered in wall paper. I was expecting lathe and plaster to be honest. Two of the walls are exterior walls and I have no idea if there is any insulation behind the boards. Not sure what to do. I need to run some new electrical outlets, then sheet rock the room but I am apprehensive about ripping into the walls. Are there any potential health risks from materials used then? Please help!!