This was supposed to be just the first part of a three-phase project my sister was working on, and it is tragic she never got the chance to start phase two or three. But she made some important conclusions about the efficacy of retrofits from her data on over one million homes, what information is needed for them, and how to do them most efficiently. The article was published recently in Energy and Buildings. You can read the full article for free, on the online MIT library here.