A twin over full bunk bed provides you with a twin bed on top of a double or queen sized bed beneath. Although many styles are available, mission-style wood frames are commonly purchased for the sturdy frame and the simple design. This type of bunk bed is not difficult to assemble, but having a helper can make assembly faster. Most manufacturers provide you with everything you’ll need to assemble your bunk bed, including bolts, slats and rails. Mattresses are usually not included, but the retailer can recommend the appropriate sizes when you purchase your bed.
Insert the barrel nuts provided with your bunk bed into the mounting holes at both ends of each side rail. You should have a total of four rails and 16 barrel nuts, which are small cylinders. Some bunk beds have these already in the holes, so if you did not receive barrel nuts with your bunk bed check the holes in the rails.
Set the headboard against a wall and attach the side rails by inserting two of the bolts provided through the headboard and into the rails at each side. Tighten the bolts with an Allen wrench.
Attach the other end of the rails to the footboard by inserting two bolts through the holes at each side of the footboard and into the rail, and tightening with the Allen wrench.
Align the center support onto the full bed frame so that the mounting holes line up with those in the center of the headboard and footboard. Insert the screws provided with your bunk bed and tighten with an Allen wrench.
Place the assembled full bed frame in the location you’ve selected for the bed, orienting the headboard and footboard appropriately.
Line up the remaining two side rails so that the holes at the end align with the holes in the twin headboard. Insert two bolts through the twin headboard and into the rails, and tighten. Insert two bolts through the footboard and into the rails at the opposite end, and tighten.
Install the guard rails on either side of the twin bed if these are provided with your bunk bed. Typically the rail will have slots that fit over the side rail and these are screwed in place. Secure the rail with the screws provided.
Install the slat kits provided with your bunk bed onto the assembled twin and full frames, and secure each with the wood screws provided. On most wooden frame bunk beds, you'll find pre-drilled holes at either end of the rails and in the center for the screws, which are needed to secure the slats.
Locate the mounting holes on top of the full bed headboard and footboard. Insert the metal pins provided with your bed into these holes.
Lift the twin bed over the full bed and line up the pins with the holes in the bottom of the headboard and footboard legs. Slide the twin bed over the pins and make sure it is pushed down fully over the pins at both sides on each end.
Ensure that all bolts are tight so that the bunk bed frame doesn't move or wobble, and install the mattresses.
The twin mattress should rest at least 5 inches below the edge of the guard rails to prevent falling.
Use the manufacturer recommended size of mattress for your bunk bed.
Check the bunk bed periodically to ensure the components haven't come loose. Tighten bolts as needed.