How to Build a Bunk Bed With a Full Bed Underneath

A bunk bed with a full bed underneath can be a unique and attractive bedroom addition. The bottom bunk provides a comfortable sleeping space while the top bunk allows for a child or overnight guest. This kind of arrangement is especially nice for a cabin or other place where parent and child might share a sleeping space for the night.

Things You'll Need

• 4 beams, 2 inches by 4 inches by 72 inches long
• 2 beams, 2 inches by 4 inches by 53 inches long
• 2 beams, 2 inches by 4 inches by 39 inches long
• 1 plywood sheet, 1/2 inch by 75 inches by 39 inches
• 1 plywood sheet, 1/2 inch by 75 inches by 53 inches
• 4 posts, 6 inches by 6 inches by 72 inches long
• 2 posts, 6 inches by 6 inches by 12 inches long
• 1 wooden dowel, 1 inch in diameter by 80 inches long
• 16 bolts, 8 inches long, with matching nuts and washers
• Power drill with drill and screwdriver bits
• 1 1/2 inch auger bit
• Crescent wrench

Instructions

Lumber Preparation

1. Cut your lumber to the dimensions noted in the Things You'll Need list. Many home improvement centers will cut them for you for little or no charge.

2. Drill two holes near each end of your 39-inch beams. Place the holes 3 inches from the end of the beam, vertically stacked 3/4 inch apart. Use a drill bit the same diameter as your bolts.

3. Drill four holes in each of your 53-inch beams. Place two holes, vertically stacked 3/4 inch apart, 3 inches from the end of the beam. Place the other two holes, also stacked vertically, 36 inches from the same end of the beam.

4. Drill four holes in each of your posts using the same drill bit you did to drill the beams. The holes should be 3 inches from one side of the beam and located 12 inches and 12 3/4 inches from either end of the post. All four holes should run parallel to each other.

5. Drill a hole in two posts running parallel to the other holes using the 1 1/2 inch auger bit. Place this hole on center, 4 inches from the end of the post. You may want to start with a narrower bit and gradually widen out to the full 1 1/2 inches.

Twin Mattress Frame

1. Form a square using two 72-inch beams and the two 39-inch beams, with all beams lying on their narrow sides. The longer beams should be inside the shorter beams.

2. Connect the beams with two screws per joint, driving through the edge of the shorter beams and into the end of the longer beams.

3. Lay the smaller plywood sheet on top of the frame and attach it with one screw at each corner and one screw at the center of each side.

Full Mattress Frame

1. Form a square using two 72-inch beams and the two 53-inch beams, with all beams lying on their narrow sides. The longer beams should be inside the shorter beams.

2. Connect the beams with two screws per joint, driving through the edge of the shorter beam and into the end of the longer beams.

3. Lay the larger plywood sheet on top of the frame and attach it with one screw at each corner and one screw at the center of each side.

4. Place one of the shorter 6-inch by 6 -inch posts in a corner of the frame furthest from the drilled holes. Screw it in place by drilling a screw into each corner of the post, through the plywood sheet and into the end of the post.

5. Repeat this procedure with the other short post, mounting it in the other corner farthest from the drilled holes.

Assembly

1. Move all components to the bedroom where you plan to install the bed. The fully assembled bunk will be heavy and unwieldy.

2. Set up the support posts so that all the holes run parallel to the wall where you'll place the long side of the bed. The two larger holes should be at the top on the side furthest from the wall.

3. Mount the full bed frame by sliding bolts through the holes in the posts and the corresponding holes in the support beams. Tighten the screws with the crescent wrench. Place the frame so that the shorter support beams point downward and contact the floor.

4. Mount the twin bed frame by sliding bolts through the holes in the posts and the corresponding holes in the support beams. Tighten the screws with the crescent wrench.

5. Slide the dowel through the 1 1/2 inch auger hole to provide a safety rail for the upper bunk.

6. Add appropriate-sized mattresses to each bed frame and your project is complete.

References

• Bunk Beds Central: Free Bunk Bed Plans
• Gene Brick; Furniture Hobbyist; Hillsboro, OR

Resources

• The Better Sleep Council: What Size Mattress is Best?