How to Cut Rafters to Install an Attic Ladder

Position a step ladder beneath the desired installation area. Activate a stud finder, and run it across the ceiling to locate joists. Mark the location of the joists with a pencil. Move the stud finder beyond the desired width of the opening, locate the joists, and use the pencil to create marks that correspond to the first set of marks.

Align a straightedge with a corresponding set of marks, and run the pencil along the straightedge to lay out a line that indicates the path of joists across the ceiling. Use the straightedge and pencil to mark the path of the remaining studs in the installation area. You will end with a set of parallel lines running across the ceiling.

Select a joist to support one side of the attic ladder's square frame. Mark the width of the frame on the joist's layout line. Align the straightedge perpendicular with the marks, and run a pencil along the straightedge to lay out lines that represent the location of the frame's adjacent sides. Lay out a final line to represent the remaining side of the frame.

Score the lines that represent the frame's location with a utility knife. Cut through the scored lines with a drywall knife, and remove the square of drywall from the ceiling. If a joist runs through the center of the opening, cut the joist.

Lay out a perpendicular cut line across the face of the joist, roughly 1 1/2 inches from the edge of the opening. You must mark the line 1 1/2 inches behind the opening to accommodate the thickness of the framing lumber that you will use to frame the attic ladder's opening. Create a similar cut line on the joist at the opposite edge of the opening.

Measure the distance from the floor to the ceiling drywall with a tape measure. Mark two pieces of framing lumber to this length. Cut the lumber with a circular saw. Wedge the lumber between the floor and the ceiling directly beneath the portions of the joist that you will cut. Support the joist to prevent the ceiling from sagging after you cut. Have a partner stabilize the lumber braces.

Cut through the joists along the cut lines with a reciprocal saw. Stop short of cutting through the ceiling drywall. Remove the severed portion of the joist from the attic. Measure the distance between the joists that surround the severed joist. Mark and cut two pieces of framing lumber to this length. These pieces form two sides of the opening, and they span between the intact joists that surround the severed joist.

Lay the cut pieces of lumber on the drywall inside the attic. Align the lumbers' ends with the joists that surround the severed joist, and butt their faces against the exposed ends of the severed joist. End nail the lumber to the intact joists with a hammer and nails. Face nail the lumber to the exposed ends of the severed joist.

Measure the distance between the newly-installed crossbeams. Mark and cut a piece of lumber to this length. This piece spans between the crossbeams to form the remaining side of the attic ladder's opening. Align the lumber flush with the remaining edge of the opening. End nail the lumber to the crossbeams with a hammer and nails. An original joist forms one side of the frame, the crossbeams form two sides of the frame, and the last piece of lumber forms the final side of the frame.