How to Build a Ladder for Bunkbeds

Lean one 2-by-4-inch board against the top bunk and place the bottom of the board about 12 to 18 inches out from the bottom bunk to find the angle that seems comfortable for climbing.

Make a pencil mark on the board at a point about two inches higher than the spot where it touches the top edge of the upper bunk mattress.

Lay the board down on the floor and align the second board side by side directly against it with both ends lined up.

Measure the length from the pencil mark to the other end of the board and round the measurement to the nearest whole number. For example 71 5/8 inches would become 72 inches.

Measure both boards to that new length and, using a carpenter's square, draw a straight line across the face of each board at that measurement.

Cut off the excess lumber above that line on each board with a saw.

Measure and mark, from the bottom of each board, a new point one inch higher up the wide face of the board and draw a second straight line across using the square as before.

Lay a ruler across from one bottom corner to the line on the opposite side and draw another line diagonally between them.

Saw off those marked corners on both boards.

Measure over 1 1/2 inches along the line you drew on the bottom of each board and mark that point with a pencil. Make the same measurement at the top edge of each board and, using those center points, draw a straight line from one end of the board to the other.

Start at the bottom of the board and measure along that center line to find the placement for the ladder rungs. Mark the first point at 8 inches from the bottom and other points exactly 10 inches apart from that point to within a few inches of the top, depending upon the length of your particular ladder. Do not place a rung higher than the top of the upper bunk mattress or lower than 10 inches from the top of the boards.

Raise the boards up on sawhorses or other support to prevent damaging your floor, then drill 1 1/4-inch diameter holes all the way through both boards at the marked points.

Cut as many dowels in half as needed to get the correct number of rungs for the ladder. These will be either 18 or 24 inches depending upon the finished ladder width you have decided upon.

Sand all the parts of the ladder starting with coarse and working to fine grit sandpaper until everything is smooth. Do not sand the interior portions of the drilled holes or the last inch of each dowel. Those should remain slightly rough to create a firm glue bond within the joints.

Wipe all the boards with a damp rag or tack cloth to remove dust, then test fit the dowels into the holes. They should fit snugly.

Apply a generous bead of glue all the way around one end of a dowel and, with the inside of one board facing up, seat it firmly into the lowest drilled hole. Use the same procedure for each subsequent dowel until all rungs are in place on one side.

Line the second board up with the rungs in the proper orientation, then quickly put glue on the exposed ends of each rung and fit the second board in place over them before the glue dries. You may need to use a mallet or block of wood to “hammer” the second board in place.

Turn the ladder over on its side and tap each dowel until it lies flush with the edge of the board facing up, then turn it to the other side and do the same. Finish adjusting by lying it flat again to ensure everything is level and all the rungs are properly seated, with none falling short of the edge or poking out beyond the board faces.

Wipe off excess glue with a damp rag before it hardens.

Allow the glue to dry completely, then finish by sanding any rough points on the ladder and applying a stain or paint as desired.