These instructions assume you are building a bunk bed for children using two twin bed mattresses. By assembling these bunk beds yourself, you can easily save a hundred dollars or more off the price of buying retail. When choosing wood, simple pine is cheapest and easily strong enough.
Build the Mattress Frames
Gather two of each type of beam, one plywood sheet, 12 1-inch wood screws, eight 3-inch wood screws, the nail and the drill.
Drill two holes at each end of one 75-inch beam using a drill bit slightly smaller than the diameter of the 3-inch wood screws. Drill into the face (not the tip). Place the holes 1 inch from the end of the beam, lined up horizontally across the beam, about ½ inch from the edges and from each other.
Line up one 38-inch beam perpendicular with the end of the 75-inch beam. The beams should form an "L" lying on their narrow sides. Square off so the outer edges line up together. Stick the nail through the screw holes in the 75-inch beam, pressing hard enough to mark the 38-inch beam.
Using the same drill bit, drill two holes in the tip of the 38-inch beam where you've marked it with the nail.
Repeat steps 2 and 3 for the other end of the 75-inch beam.
Using the screwdriver bit, connect the 38-inch beams to the 75-inch beam using 3-inch wood screws in the holes you've just drilled.
Repeat step 2 for the second 75-inch beam.
Using a drill bit slightly wider than the diameter of the bolts, drill two holes at each end of each 75-inch beam. Drill into the face (not the tip). Place the holes ½ inch from the inside edge of the the 38-inch beam (approx 2 inches from the end of the 78-inch beam), lined up horizontally across the beam, approximately ½ inch from the edges and from each other.
Lay the plywood sheet on top of the frame.
Using 1-inch wood screws, attach the plywood sheet to the frame. Place one screw in each corner. Space two screws evenly along each longer side, and one screw at the center of each shorter side.
Prepare the Support Frames
Using a drill bit slightly wider than the diameter of the bolts, drill four holes into each of the one of the 8-by-8-inch posts. Two holes should be placed 1 foot from each end of the post, 2 inches in from the edge of the wood. Place the other two holes 2 feet from the other end of the post, 2 inches in from the edge of the wood. If you are using twin mattresses with box springs, place the second two holes 2½ feet from the end of the post.
Using the auger bit, drill a 1¼-inch-diameter hole perpendicular to the line of the other drill holes. Place this hole 6 inches from the end of the post.
Repeat steps 1 and 2 for the other three posts.
Assemble the Bunk Bed
Line up one bed frame with the lower set of holes drilled in the posts.
Use eight of the bolts and washers to connect the bed frame to the posts, with the nuts on the inside of the bed frame.
Repeat steps 1 and 2 for the upper bed frame.
Slide the dowels through the widest holes to serve as safety rails.
Add mattresses and bedding.
Sand the wood using sandpaper or a power sander. If you want to paint or finish the wood, do so after sanding and before additional construction.
Things You'll Need
Four 8-by-8-by-72-inch posts
Four 2-by-4-by-38-inch beams
Four 2-by-4-by-75-inch beams
½-by-38-by-75-inch plywood sheets
Two 1-by-75-inch dowels
16 3-inch wood screws
16 10-inch bolts with washers and nuts
24 1-inch wood screws
Drill with regular, auger and screwdriver bits
Long, thin nail or needle