How to Install a Replacement Exterior Sliding Door
- 1). Stand the pre-hung sliding door unit in the door opening, so the casing lines up with the interior edge of the jamb. Keep the doors closed.
- 2). Set a level along one vertical side of the door unit. Insert shims around the edges, between the jamb and the casing, until the level reads level and square.
- 3). Open both sides of the sliding doors enough to get at inside edges of the casing. Secure the casing by shooting screws out through the sides and into the surrounding jamb. Put screws every foot or so up and down each side of the casing. (Note: If there are pre-drilled holes for the screws, then use those.)
- 4). Use a utility knife to cut off the shims where they overhang the sides of the casing.
- 5). Install the pre-cut door trim around both sides of the opening using your trim nailer, so the trim spans the space between the casing and the surrounding frame. Run caulk around the edges of the trim where it meets the wall and the casing.
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