I work for a general contractor who is remodeling a home that was built in 1915 with plaster walls on wood lath. The remodel is fairly extensive (upgrades to electrical, mechanical, plumbing, insulation, tear out walls, build new walls, etc.). I am trying to decide if it will be more economical to tear off all of the plaster and lath or just cut holes and notch channels where necessary. Any suggestions? Some of my questions are: Can we patch the holes and channels that we dig with drywall so that it matches the existing plaster? When we cut a new hole, will it damage the surrounding plaster so much that we should just remove all of it? Should we do a skim coat over everything after all of our patchwork is complete in order to blend the new with the old? We are considering blowing cellulose insulation into the wall cavities to increase the R-value - I have never done this before, What problems might we run into trying to fill the whole cavity and patching the holes every 16"? I would like to read some thoughts from anyone with experience or expertise in this kind of work. Thank you.