We have a Cape Cod style house and we will be adding a shed dormer to the back of the house. The dormer back wall will be built on top of the first floor back wall (for load bearing purposes). Our current roof pitch is 12/12, which means the current floor joists are angled at the ends to match the roof pitch. When we take the old roof off and raise the new dormer end wall, we'll obviously need to do something about the end of the joists that are angled. What's the best method to deal with this? Sister smaller joists that will reach the edge of the first floor top plate? OR put some blocking in and then cap with a rim joist? OR something else? Thanks for the help!