Innerspring mattresses are the most common type of crib mattress in the United States. Most adult mattresses are also innerspring mattresses, so this kind of mattress is familiar to most people. Innerspring mattresses get their shape from the spring-link coils embedded inside them. These mattresses can be rather complicated inside: they are made from layers of springs and sometimes include other design features like support rods that give the mattress structure. In general, innerspring mattresses are slightly heavier and more expensive than foam mattresses.
Evaluating an innerspring mattress can be tricky because there are several factors to consider, including the number of coils (this is the feature most manufacturers rely on in their marketing campaigns), as well as the gauge of the steel used in the coils. Mattresses with a higher coil count and lower gauge steel — meaning the steel is thicker —are usually more expensive. The final element in quality is the mattress covering. You can look for waterproof or fabric mattress covers.
While most innerspring mattresses feature coils that are joined together with a steel frame inside the mattress, there is some variation. A pocket spring mattress features steel coils that are individually sowed into pockets of fabric instead of joined together. This allows the springs to move individually, instead of each spring affecting the one next to it. The result is a very comfortable, durable mattress. The springs in these mattresses tend to last longer, and they are often considered the most comfortable type of crib mattress. Their main drawback is price: pocket spring mattresses are among the most expensive crib mattresses.
Other types of crib mattresses: