John writes from Beachwood, Ohio: "Home was built in 1935 and has a "balsam wool blanket" about 1/2 inch thick rolled out across the top of 10" rafters held in place with strips of wood nailed into rafter. In areas the blanket has separated and fallen to the bottom of the ceiling. Electrical wiring runs under the blanket. I am using your new atticat blown in insulation to R49 or 18". I have started to cut the blanket away from the rafters and let it fall to the ceiling (bottom of rafters) before blowing in the atticat. Not sure if this is the proper thing to do? Should I be concerned about the electrical wiring in contact with blanket and atticat insulation?"

Answer: If the wiring is insulated it should be fine. If it is old knob and tube wiring, keep the insulation three inches away from it. You can recognize knob and tube wiring by the ceramic knobs or tubes in which the wire gets attached to, or passes through, at the joists or studs.