Buying a Bunk With Double Bed A bunk bed with a Double Mattress bunk bed bed is a great option to free up space in a room that is occupied by children. These beds offer both playing and sleeping space for kids, and they are also a great option for adults when guests are in. A twin-over-full bunk bed is perfect for siblings who share bedrooms. It can also accommodate an additional full-size bed in the bottom bunk for guests. Durable construction The sturdy bunk beds for adults are constructed to be able to withstand the weight of adults sleeping. Find frames that are rated to support at 500 pounds on each mattress and meets entrapment hazard standards. Be sure that the frame is constructed of durable materials that can withstand normal wear over time. If you have a limited space, consider getting a bunk double bed with desk bed with twin top and full-size bottom beds to save space. The beds are available in a variety of paint finishes and can fit twin mattresses.