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How to Install an Exterior Fire-Rated Door

Exterior doors offer special protection when rated against fire. These doors can withstand the elements, fire and low levels of water. Additionally, these doors are very useful for keeping homes and buildings well insulated since they allow far less air loss than doors with lower ratings. Installing these doors requires precision and a level location. A 3-foot carpenter's level is helpful to ensure that the door frame is level to allow for easy opening and closing of the door. This project requires basic tools and some familiarity with the door installation process to help it go smoothly.

Things You'll Need

  • Tape measure
  • Reciprocating saw or file
  • Caulking
  • Putty knife
  • Shims
  • Hammer
  • Drill
  • Drill bits
  • 3-inch galvanized wood screws
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    • 1

      Measure the doorway opening and compare it to the size of the exterior fire-rated door. Remove portions of the doorway, if needed, with a reciprocating saw. File down sections that only require slight adjustment. Try to wedge the door frame in place and adjust the doorway, as necessary, until the frame fits. Remove the door frame and apply a thick layer of caulking all the way around it. Reposition the door frame in place and remove all excess caulking with a putty knife.

    • 2

      Use a carpenter's level against the sides of the door frame with the door open to determine if the frame needs to be adjusted. Open and close the door repeatedly to see if the motion is impacted by the frame's position. Set shims around the frame if necessary and hammer them in place to level the frame. Break off any excess shims that stick out from the door frame.

    • 3

      Drill holes into the center of the frame and into the doorway, spacing the holes every 12 inches around the frame with the door open. Set 3-inch galvanized wood screws into each hole and tighten them down completely to attach the door firmly in its level position.

    • 4

      Position the trim boards, if necessary, against the interior and exterior of the door frame. Drill out any attachment holes and attach the trim with 3-inch galvanized screws.