While bunk beds with futon on bottom can be purchased already built, it is possible to build one out of two separate loose mattresses. Loose mattresses are very useful furniture with their sofa / bed combination style. It is also possible to build bunk beds out of loose mattresses so that you get a bed / couch on the bottom and another bed at the top. To build bunk beds with futon on bottom you need: two futon sets, timber, hammer and nail, drill and bits, nuts and bolts.
Instructions to build bunk beds with futon on bottom take two futon sets, preferably two that are exactly the same. Measure the length, width and thickness of each piece of wood that make up the headboard and footboard, especially the width and thickness of the posts. Construct your own bunk bed headboards and footers using your own wooden load. The posts should not be more than seven feet high, but should probably be wider and thicker than the originals – possibly up to twice as thick. Drill holes in headboards and feet big enough for the bolts that came with futon frames. Attach the frames to the headboards and footers using nuts and bolts. If the posts you use are thicker than the original futon posts, you may need to bolt longer than the original ones – but they should have the same width.
Next steps to build bunk beds with futon on bottom make sure that the futon frames are properly attached to the head and footer. Make sure the bolts are tight and the frame should not vibrate at all. This is especially true for the upper bunk. Build a ladder to access the top bunk. It may be best to attach this ladder to the headboard or footboard to hold it in place. (Since the frame is likely metal, attach that is not likely.)