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Retrofit Improvements: Double Entry Door Reinforcement

Retrofit Improvements: Double Entry Door Reinforcement

Some homes are equipped with double entry doors, hinged at the sides and latched in the middle, often called french doors. These doors typically consist of two active doors, one of which is held closed with slide or barrel bolts through the top and bottom (i.e., head and sill jambs), while the other swings freely or closes against the temporarily-fixed adjacent door panel. Because double doors span a wide opening and latch against each other, the closure where the doors meet at the middle of the opening is susceptible to being forced open by wind. Several options exist to make this type of opening more secure against force from the outside.

Double doors should be made of a minimum of 2” of solid wood, 1 ¾” steel, or 1 ¾” fiberglass wrapped polyurethane cores to assure adequate strength against wind pressure at bolt holes and hinges. Alternatively, steel reinforcement pieces which wrap around the door at the bolt holes and hinge areas to prevent splintering and shattering under force are available for various door thicknesses.
As with all impact resistant doors, door jambs should be secured to the framing, 6” from each corner and approximately 1’ on center all around with 3” screws. Locksets and dead bolts should have a minimum of 2 ¾” backsets (extension length), and barrel bolts should have a minimum of 3” extension and fasteners that secure the hardware to the door.

If the doors are in need of replacement, consider changing the opening and door size to 36” wide or installing a wind rated single door with sidelights. Alternatively, converting doors with covered entrances to swing outwardly increase the doors’ ability to resist force from high winds. When high winds strike outswing doors, they will close more tightly against the door frame. Permanent shutters may also serve as protection for wide door openings, however, because a door may need to remain in use as an emergency egress, shutters that close from the outside are not practical.

Cost of this retrofit will depend on the option(s) selected and whether or not a homeowner chooses the “Do-It-Yourself” route. The hardware for a retrofit starts at about $110. Door replacement and shutters will increase the cost. In high wind locations, homeowners are urged to cover all door and window openings with impact rated products.