Exterior double French doors are generally used as patio doors. They are installed in place of glass sliding doors. Exterior double French doors have wooden frames with glass panels that let in sunshine. Most sets now come with the doors already attached to their doorjambs or door frames, which makes at-home installation even easier.
Caulk the door frame thoroughly. Apply caulk on the seams of the door frame with a caulking gun. Let the caulk dry completely before you proceed.
Center the exterior French doors in front of the space where they will be installed. Ask a friend to help you hold the doors upright so that both doors are held up at the same time.
Slide the exterior French doors into place. Position the bottom of the French doors first, then push the top into place. Tap the top of the frame lightly so that the doors fit into the space correctly.
Check that the doors are even using a level. Secure the doors and nail in each side of the doorjamb.
Recheck that the doors are level and properly placed. Once the doors are correctly positioned, drill in screws to attach the doors and their frames to the surrounding walls.
Spread caulking over the frame edges and the outside of the doors to make the door waterproof and prevent air from leaking out.
Installing exterior double French doors is much easier when you have another person to help.
Wear protective gear when caulking.