How To Replace An Exterior Door Sill. Install a membrane or pan flashing that protects the sill the bottom of the jack studs and if possible the face. If your threshold is in rough shape replace it.
If your threshold is in rough shape replace it. Remove it by unscrewing it from its position using the screws to expose the sill. Door was thrown in trash and a new one ordered.
Caulk around the outside of the door sill.
Install a membrane or pan flashing that protects the sill the bottom of the jack studs and if possible the face. In most cases simply order a new door the same size as the old one. Rotted 2 4 sill plates studs and exterior sheathing were found on either side of the door. Pry loose the old trim.