How to Frame a Closet With a Sloping Floor

Install the Floor and Ceiling Plates

• 1

  Measure and cut 2-by-4 dimensional lumber for the floor plates. Use a circular saw to cut the boards.

• 2

  Lay out the floor plates, using a framing square to ensure the boards are square with the existing walls.

• 3

  Make pencil marks on the floor plates to indicate the placement of the wall studs. The simplest way to do this is to lay the small end of a framing square, which is 1 1/2 inches wide, on the plate and make pencil marks on both sides.

• 4

  Mark for triple wall studs at corners, and space the rest of the studs 16 inches apart, measuring from the corners toward the walls. Allow for an additional stud along the existing wall.

• 5

  Measure 2 1/2 inches wider than the closet door and make a double stud marking to represent the rough door opening. For example, if your closet door is 36 inches wide, you will need a 38 1/2-inch rough opening.

• 6

  Attach the floor plates to the floor with a framing nailer, fitted with 16d nails. Shoot one nail about 1/2 inch away from the outside edge of each stud marking. Do not nail through the plate where the closet door will be located.

• 7

  Cut another set of boards, identical to the floor plates, and lay them on the floor outside the plates. Make sure the ends match up perfectly and then transfer the stud markings from the floor plates to the matching boards.

• 8

  Attach the matching boards to the ceiling joists, using a laser level to ensure that the outside edges of the ceiling plates match the outside edges of the floor plates. If one of the ceiling plates does not cross the joists, you will have to install backers between the joists from the attic. Backers are 2-by-4 boards, cut to fit between joists and installed with the wide flat side flush with the ceiling drywall. Space the backers 16 inches apart.

• 9

  Nail the ceiling plate to the ceiling joists, or to the backers, using 16d nails and inserting one nail about 1/2 inch from each stud marking.

Frame the Walls

• 10

  Measure and cut each stud when you’re framing a wall on a sloped floor. Some studs will be slightly longer than other studs.

• 11

  Install a triple stud for every outside corner. If you’re framing a closet to span the entire distance from one side of the room to the other, you won’t have to do this, but if the closet has an outside corner, it needs three studs if you want to finish the inside of the closet with drywall.

• 12

  Position each stud between the ceiling plate and the floor plate and use three 8d nails to attach the tops of the studs and three more 8d nails to attach the bottom of the studs. The best way to do this is with a technique called “toenailing,” which involves shooting the nail into the side of the stud at a 45-degree angle so it enters the floor or ceiling plate. On one side of the stud, insert two nails, evenly spaced. On the other side, insert one nail in the center of the stud.

• 13

  Attach the outermost of the two studs that form the rough door opening between the ceiling and floor plates. These are “king studs.”

• 14

  Make a header to fit between the two king studs. To make the header, cut two 2-by-4s to match the distance between the king studs, and nail the two boards together with 16d nails.

• 15

  Measure 82 inches from the floor (not the floor plate) and attach the header to the king studs. Shoot four 16d nails, two per board, evenly spaced, through the outside of the king studs and into the ends of the header boards. The bottom of the header should be 82 inches from the floor.

• 16

  Cut two studs, 80 1/2 inches each, and install them on the inside of the king studs, directly below the header. These are trimmer studs. Toenail them in place with two 8d nails at the top and at the bottom.

• 17

  Cut out the floor plate even with the inside edges of the trimmer studs, using a reciprocating saw. Your closet is now ready for drywall.