First, Green Building Advisor has been a godsend to this newbie energy retrofit on an old house.  Thanks to Martin and the crew for all the great resources, especially the series, https://www.greenbuildingadvisor.com/article/how-to-do-everything.

My 1899 farmhouse (Climate Zone 4/5) is being resided so I plan to add some energy benefits in the process.  The original walls are beadboard wall paneling, 2×4 studs, and siding. The siding will be removed. I plan to add Rockwool batts in the stud cavities, add a sheathing and WRB, and rain screen and then new wood siding.

1) I’m leaning toward Zip-R3 for the combination sheathing and rigid foam insulation. I’m worried about long-term survivability of the taping. Should I consider having it installed with using the liquid flashing over the seams and holes as I’ve heard recommended? Should I be concerned about the use of Zip or Zip-R3 on the remodel won’t work as well as new construction? Is there a better benefit to using plywood sheathing, WRB, and then rigid foam insulation? 

2) Besides adding to the energy gains, I’m also wanting to maintain the historic nature of the building. The large (5′ x 2′) windows are beautiful and a great feature. They need work but are generally in great shape. I’ve read about ways to weatherstrip, insulate window pockets, and use of blinds and storms; however, I can’t find much information about how to better seal and flash the windows while I have the siding off.  I plan to add trim to keep the window exterior profile the same but I’m hoping to improve on their performance while I’m at it. Tips, tricks, suggestions?

Thanks everyone for your assistance with my project. 

Rob.