I live in a cape built in 1949. There are literally 3 inches of eves on the house which means no ventilation/circulation. I have a new roof with ridge vent and what looks like adequate insulation behind one of the knee walls upstairs (no access to the other knee wall). But the summers are over 100 degrees up there and in the winter you can almost see your breath. There is one single vent to the upstairs. There are louvers on the side of the house but I imagine they don't circulate much air. Being a cape, you have the ceiling/dry wall, wood planks and then shingles so it's no wonder you can't heat/cool this house. Is blown in insulation an option? Do I need to get insulation in the 3 inch space between the drywall (plaster) and roof? How do I insulate this thing?