How to Add a Window Above the Door Cutting Into the House

Slip a pry bar or hammer beneath the door's casing and pry the casing from the door jamb. Set the casing aside for reuse after you install the window. Run a stud finder across the drywall beside the door's side jambs to locate the door's king studs. Mark the king studs' centers on the drywall with a pencil. King studs are the outer set of the four studs that surround a door opening.

Run the stud finder across the intersection between the wall and ceiling above the door to locate the king studs. Mark the king studs' location at the intersection between the wall and ceiling. Lay a straightedge between the corresponding king stud marks and run a pencil along the straightedge's side to draw a plumb line from the door's top jamb to the intersection between the ceiling and wall. Create a similar mark on the opposite side of the door opening.

Score the plumb lines with a utility knife. Score the intersection between the lines with a utility knife. Pry the scored portion of drywall from the area above the door with pry bar or hammer. Attach a demolition blade to the reciprocating saw. Use the saw to sever the header and cripple studs from the door's rough opening. Cripple studs are the short studs that run between the header and wall's top plate. Set the header aside for reuse.

Measure the width of the door opening and mark the width on a piece of framing lumber that is equivalent in size to the wall's studs. Cut the lumber to size with a circular saw. Set the lumber in the previous location of the header and fasten the lumber to the rough door opening, through the king studs' faces, with a framing nail gun. Fasten the door's top jamb to the lumber with a finish nail gun, nailing through the jamb into the lumber.

Measure from the top of the lumber that replaced the header to the dimension that represents the top of the window's required rough opening. Mark the top of the window's opening on the king studs with a pencil. Align the reserved header with the marks and fasten the header to the king studs with a framing nail gun. Measure the distance between the top of the header and the bottom of the wall's top plate. Cut cripple studs to this dimension and fasten the cripple studs between the header and top plate with a framing nail gun.

Insert the window into the opening between the door's top jamb and the relocated header. Attach a driver bit to the power drill. Drive deck screws through the side of the window frame to secure the window header, king studs and bottom of the rough opening.