Before You Begin
You'll find retractable screen doors sold at home centers and lumberyards. Bring the measurement of the height and width of the door so you can choose one the correct size.
Measure the width from the inside surfaces of the exterior trim. Measure the height from the bottom of the exterior trim to the bottom of the door sill.
Your door must be an in-swing door, which means it opens into your house. All four corners must be square and the door frame and exterior trim no more than 1/4 inch out-of-square, so the retractable screen can be installed and function properly.
Carefully read the installation instructions in the manual that come with the retractable screen. Determine if your sill is short, flush or extended. A sill is short if it stops short of the exterior trim; it is flush if the sill stops flush with the exterior trim, and extended or long if it extends out past your exterior trim. Follow the instructions for the type of sill at your door.
Determine which side of the door you want to install the screen housing. In most single door installations, installing the screen housing works best on the hinge side of the door.
Thoroughly clean the door jamb and remove any existing screen/storm door. Patch the holes and if painting is needed, do so before installing the retractable screen.