How to Install Exterior Doors on Homes
- 1). Assess the rough opening. Make sure the opening is the proper size, and that the framing is plumb and level (within normal limits). If the opening is the wrong size, or out of level more than ¼ inch in 4 feet, you'll have to reframe the opening.
- 2). Mark the hinge locations on the butt side trimmer.
- 3). Plumb the trimmer. Hold the 6-foot level against the butt side trimmer, and use shims at each hinge location to get the level perfectly plumb. Fasten the shims in place using #4 box nails.
- 4). Check the condition of the rough opening's threshold with a 3-foot level. Place a shim at either end of the threshold to get it perfectly level.
- 5). Lay down a thick bead of siliconized latex caulk on the threshold.
- 6). Set the door in place from the outside. Let the door's threshold rest on any shims placed in step 4, and push the door into the opening until the brickmold contacts the wall sheathing.
- 7). Push the hinge side (butt side) of the door against the shims placed in step 3, and nail the door in place with galvanized casing nails, nailing through the brickmold and into the wall sheathing. Nail only the butt side for now.
- 8). Open the door and replace one of the inner screws on the jamb side of each hinge with a 3 ½ inch long #10 screw. These screws will go through the door jamb and shims and into the trimmer. Do not use an ordinary deck screw; they aren't strong enough.
- 9). Close the door, and from the inside, shim the strike-side jamb and the head jamb to obtain an even reveal between the door and the jamb. Finish nailing the brickmold to the wall sheathing.
- 10
Seal any gaps between the door jambs and the framing with minimally-expanding urethane foam.
Source...