How to Install Wood Siding Around a Sliding Door

Measure the top, bottom and sides of the sliding door frame.

Cut the trim pieces from sealed trim lumber. The side trim pieces will need to be cut so they are flush with the top and bottom of the door frame. The top and bottom pieces will extend out to be flush with the sides of the side trim pieces.

Apply a strip of ice and water shield to the bottom flange and wall sheathing. Attach additional strips up the sides and across the top of the sliding door frame, overlapping the pieces. The top piece should be attached to the upper flange and wall sheathing.

Install the bottom trim piece to the siding with finishing nails. This piece of trim should be the same width as the door. Apply caulk to the back of the trim piece for a tighter seal.

Install the side pieces of trim to the sliding door with galvanized finishing nails. Nail approximately every 12 inches. Apply a bead of caulk to the side trim pieces as well. The side trim pieces should be flush with the top and bottom edges of the door frame.

Install a piece of Z-strip flashing above the sliding door frame. The Z-strip flashing should slide underneath the bottom edge of the house's existing siding.

Slide the top trim piece under the Z-strip flashing. Apply a bead of caulk prior to installation to form a water-tight seal. Fasten with 2-inch galvanized nails every 12 inches.

Apply paintable caulk around the exterior trim and the house siding. Take the time to fill in any nail holes and touch up any paint.