How to Install a Set of French Doors
Once you have received the new set of doors and are sure that they are the proper size for your opening, you will want to go ahead and remove the old door system from the opening. Before you set the new set of French Doors you will want to place a line of silicone sealant on the floor to help seal the new set of doors.
Next lift the new door set into the opening and make sure that it is level on all sides. This is a most important step – as if the door is not level when installed then the door wont ever close properly and may rub, stick, or be generally out of alignment when you look at it.
If the door is out of plumb (level) you will need to use shims (small pieces of angled wood) between the opening and the new prehung fame to being the prehung frame into level. Once everything is level then you can begin to screw the frame into the opening.
After you have installed several screws check the door for plumb again. One easy way to check for plumb is to look at the gaps around the door. All the gaps should be even. If the width of the gaps is not even, then the door won’t operate correctly, and you should adjust the door again with shims. It may even be necessary to remove or reposition the original mounting screws. Another trick is to take an extra long mounting screw and drive it in near one of the hinges that you need to pull back. This extra tension in the area of the hinge can adjust how the door swings and can help with alignment.
Once you have finished mounting the door and removed all the packing material, you will want to go a head and mount all the door hardware. When finished check for proper operation of the door hardware.
As a final finishing step you will want to fill any cracks or holes around the jam with some insulation. After that is complete you will need to install the moldings around the door and paint to finish.