We recently purchased a 1905 masonry colonial revival home. It has been meticulously restored and nearly everything is original (major exceptions are updated bathrooms and kitchen appliances). We have to remove all of the knob and tube, a massive three-week project happening this summer. Since we will be putting holes in the plaster to rewire ceiling lights, I was wondering if there is anything that we should do at the same time...before we repaint. Should we add insulation to the exterior walls? Anything else to help the performance of a drafty old home?