Insulating old home with no vapor barrier
I am interested adding HVAC and insulating an old family home built in 1828 in West Point Georgia. The house is one level and sits on brick piers. On the outside there is wood siding. On the inside there is wood lath cover with plaster. There is no other vapor or air barrier between the inside and outside. The bottoms of the walls are open to the elements. For the last 180 years the natural air movement through the wall has keep rot from developing. I am very concerned that if insulation is added, coupled with condensation from the heating and cooling, that moisture problems will develop in the walls. I don't want to remove all the old siding which is only slightly less dense that iron. I thought that doing poured open cell foam in the walls would be a good idea except for the potential moisture issues. Can I insulate this home without setting up a problem that will destroy it?