Building Wall Shelves in the Corner

Decide how large a shelf you want. For general storage, a shelf with 18-inch sides is large enough and will intersect multiple wall studs. If you're building the shelf for a specific object such as a TV build it to suit the dimensions of what you want to store.

Buy a 2-inch by 2-inch wooden beam and a sheet of 1-inch thick lumber. You can use pine and plywood if you intend to paint the shelf, or fancier woods if you want to stain it.

Cut two beams to match the length of the sides of your shelf. Cut two more to the same dimension, minus 1 1/2 inches. For example, if you wanted your shelf to have 12-inch sides along the wall, you would cut two beams to 12 inches, the others to 10 1/2 inches.

Cut the lumber sheet to match the sides of the wall. For 12-inch sides, you would cut a 12-inch by 12-inch square. Cut the square in half along the diagonal.

Sand and paint all surfaces of your lumber to match your tastes and the color scheme of the room where you plan to install the shelf.

Use your stud finder in the corner where you want the shelf. Mark the wall with a pencil at the location of each stud. If no studs are in the corner, mount drywall anchors every 6 inches.

Set one of your longer beams in the corner, with its end abutting the perpendicular wall. Use your level to straighten the beam, then mount by screwing it to the wall studs.

Set one of the longer beams in place, its end abutting the face of the beam you've already mounted. Screw in place as you did the first.

Repeat steps seven and eight to mount the second shelf higher or lower in the corner.

Set the triangles of lumber in place, resting on the edges of the beams you've mounted. You can secure them with screws, but gravity and friction are generally sufficient to keep them in place.

Touch up any scuffs or dings that happened during construction.