The popularity of twin bunk beds in comparison with single bunk beds is quite negligible. That explains why it’s not easy to find a proper bed. They are not so widespread, because they are not always convenient for people. If we speak about twin beds it is mostly about adults. Firstly not all adults are ready to climb up the stairs every single day. Also some of people are just unable to do it. But, certainly, these beds are used if there is a pretty tiny room, so a person has to think about maximizing space.
More often such beds are made on the request of some organization, e.g. dorms, military structures, hostels. They are not a designer value; the basic idea of them is portability, compactness and low cost of production. But if you want to buy the bed of this type it is possible, you have to either to look for it thoroughly or to buy to order. Metal twin bunk beds are in large numbers, but if you buy it to order, you may choose materials as well. These beds are used if a family is big, including several children, but the size of accommodation doesn’t allow having several beds. Of course in this case that bunk is the best alternative.
Also twin bed bunk beds can have a twin bunk in the bottom, and a single top bunk. This variation is the most widespread. It is a perfect choice for families with one child if they have only one bedroom. The bed may contain stairs in the form of step-drawers. It also helps to maximize space in the room, providing an additional place for storage. Since such a variation of twin bunk beds is quite widespread, people may buy it even if there’s no need to give a sleep place for a kid, because the top bunk can be used just as a place to store stuff, or it can be used as an unusual element for the design (a place for decoration). And let’s not forget the modern bunk beds can transform into sofas (the bottom bunk) or be in the form of loft beds, what makes them especially appealing for living-rooms.