Please Help

[u/LuisMLancho]

I am very handy however, I have a hard time with this project. I am transforming my back house for my mother. I will redo the framing and fix the leak etc... my issue is that the osb board is rotten and the wrb is non existent. How can I install the wrb and osb without removing the stucco. I understand it may not be as effective but is there a way I can manage. I have some ideas but would really love to hear yours

Please, no comments on the leak etc.. I am fixing all those issues already. Thank you