Roof flashing systems are required by manufacturer's specifications along with current building codes to be replaced with new roofing systems.  Some roofing contractors skip this step and therefore void manufacturer's warranty's.  The object is to ensure water does not "back up" along a wall and creep in behind the siding or wall or under the roofing material.  The new Ice & Water shield needs to be wrapped up the wall behind the siding or under a counter flashing and the new aluminum flashing system needs to be completed in the same manner.



The current siding needs to be loosened, removed or cut to allow for the proper installation of the Ice  & Water and the new flashing system.  This can be accomplished very easily with a little time.  If it is vinyl siding, this can be loosend or removed with your hands, hammer or prybar.  In the case of aluminum siding, the whole wall may need to be removed from the top down, due to the aluminum siding having a chance to bend.  Regarding wood siding, in some situations the bottom piece can be removed and the new Ice & water shield along with the flashing can be slid up behind all of the siding.  With wood or aluminum siding, there may be times that the siding needs to be cut up off of the roof deck.  This is when the siding is too close to the roofing system.