How to Replace an Aluminum Sliding Patio Door

Cut through the caulk and paint around the interior trim with a utility knife and pry the trim off the wall with a pry bar.

Unscrew the stops or brackets that hold the sliding door in its track and carefully remove it from the track by lifting it and pulling the bottom edge in toward you.

Unscrew the brackets or screws holding the fixed panel into place and carefully remove it from the track by lifting it and pulling the bottom edge in toward you.

Cut through the paint and caulk along the exterior door trim and pry off the trim with a pry bar.

Remove the racks from inside the door frame by unscrewing the screws holding them in position and remove the aluminum door framing by hammering the framing toward the outside.

Place a level across the threshold. If the threshold is not level, place shims on top of it every 6 to 8 inches until it is.

Place foil-backed tape over the corner at the front edge of the sill, extending it 6 inches up each side of the frame. Cut the tape at the corner so you can fit it flush against the framing. Place a second strip long the bottom of the sill so it overlaps the back of the first piece and place strips of tape on the sides and header of the door frame.

Apply two thick zig-zag beads of silicone caulk along the sill on top of the foil-backed tape.

Unfold the nailing flanges along the sides of the replacement doors.

Move the replacement doors into position over the sill. Get someone to help you with this as the doors are heavy. Slowly lift the top of the door into the wall frame. Drive two roofing nails partway into the nailing flange at the top corners to keep the door temporarily in place.

Check the spacing on each side of the replacement doors, adding shims to even them out if necessary.

Attach the aluminum framing to the wall framing by driving screws through the side jambs and into the framing. Drive roofing nails through the holes in the roofing flange.

Squeeze a drop of silicone into the holes in the bottom part of the aluminum frame over the sill to help prevent leaks. Screw the frame into the sill. Screw it into the header.

Install the sliding door in the frame, following the manufacturer's instructions.

Nail the exterior trim to the outer edges of the door frame.

Install foam backer rod into the gap between the aluminum door frame and trim on the outside of the house. Apply a thick bead of clear sealant over the backer rod.

Trim any shims you installed around the door with a utility knife. Fill the gaps around the frame on the inside of the house with spray foam insulation.

Nail the interior door casings and trim into position.