Installation of Fire Rated Steel Doors
- 1). Remove door casing and brick molding from the old door. Door casing is the trim on the inside. Brick molding is on the outside.
- 2). Insert the blade of the reciprocating saw between the door jamb and the wall studs and cut the screws or nails securing the jamb to the wall.
- 3). Remove the door and jamb as one unit from the wall opening.
- 4). Clean the wall opening by removing insulation, nails, screws and silicone. Vacuum the threshold.
- 5). Apply two parallel rows of silicone caulk across the threshold. This will prevent rain, wind and insects from coming through under the door.
- 6). Insert the new pre-hung door in the wall cavity, from the outside in. Pre-hung doors come with brick molding already attached. Push the door so the brick molding lies flat against the wall.
- 7). Shim the door so it is evenly centered in the wall opening. Measure the distance from the top left corner to the bottom right corner, and then measure the distance from the top right corner to the bottom left corner. If these dimensions are not the same, shift the door jambs up or down until they are.
- 8). Place shims between the jamb and the wall directly behind the top hinge screw hole. Install a wood screw through this hole, making sure it goes through the shims, and then into the framing studs. Repeat this step for the top hole of each door hinge.
- 9). Recheck the corner-to-corner dimensions and verify that the door is plumb. Install shims on the latch side of the door and screw the jamb to the wall studs. Check the door for proper closure and ensure that the door latch pockets line up with the jamb latch pockets.
- 10
Fill the space between the jamb and the wall framing with expanding foam. Fire rated expanding foam adds more fire protection than regular expanding foam. Do not fill the cavity with too much foam because it will over expand when dry and ooze out of the wall cavity. It may also push the jambs in, making the door difficult to open and close. - 11
Install new door locks and knobs. Install finishing nails through the brick molding, and then reinstall the interior trim. Adjust the threshold height with the adjustment screws.
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