New first steps for deep energy retrofit
The most "dangerous" things for trying to keep the air-tight status of your walls is the "penetrations" of the walls and roof for utilities-type things. Typical buildings have the majority of the electrical inside the walls and floors and ceilings... all of that has to go. If you are taking a long time to retrofit and especially if you are living in the building while renovating, you need electricity. You will also appreciate a fully functional bathroom. There are lots of ways to eliminate almost all penetrations by plumbing such as air-entry units that eliminate plumbing stacks. The problem is these things may not be accepted by building inspectors or local building codes or the plumber hired. If you start with the plumbing and electrical as a complete rebuild and have everything inside the expected inside wall surface or air-tight floor and ceiling membranes, you can have everything ready to use during construction and you know all penetrations you cannot avoid as they are already in place. The next step is opening the walls and removing the old obsolete electrical and plumbing which you know for sure is disconnected. Removing potentially dangerous things like asbestos and rodent stuff is also not going to contaminate the insides of your electrical conduit and boxes and the plumbing (because it is all air-tight and new and can be covered as needed). This is my latest plan... setting out conduit and wire chases to install a new electrical system at the point where the new inside non-load-bearing wall will be located eventually. Then I can do the plumbing systems including electrical things that interact with the plumbing (water heaters, pumps, detectors, solar thermal systems). Then finally, the new electrical and thermal heat systems are available for HVAC stuff (but will be under-sized because the walls are not made efficient yet... but something). One last benefit is if you are changing window and door placement prior to air-tight goal efforts, you don't have to worry about existing plumbing and electrical being in the way of changes. Wire chases in baseboards is a good idea as it eliminates a lot of potential air leakage through the wall. Concrete work, if needed, is far easier with running water available.