Innerspring mattresses are the most common type of mattresses. They consist of a spring zone and a comfort layer. The innerspring is the source of support and provides proper spinal alignment while you sleep.
Beneath the ticking of the mattress are the comfort layers that cushion your body at the sleep surface. The combination of various foams and fibers provide varying levels of softness and comfort. Pillow Top mattresses include additional comfort layers on top of the mattress for additional supportive comfort at the surface.
There are four main types of coil mattresses:
• Open (or Bonnell) coil mattresses have hourglass-shaped coils, which are attached to surrounding coils with a small wire spiral called a helical. This design provides good initial support and works to isolate motion transfer. However, open coils do tend to wear more quickly than other coil constructions.
• Offset coil mattresses have a construction similar to open coil but have a square head, which in theory enables the mattress to contour better. An offset coil is slightly more cylindrical in shape than an open coil which gives it durability. Serta’s latest offering in this category is our VertiCoil Premier™ Innerspring, featured in our Sertapedic® collection.
• Individually wrapped (or Marshall) coil mattresses have an individually wrapped cylindrical coil contained within separate fabric pockets. Each coil is separate so the rest of the bed isn’t disturbed by the movement of the coils surrounding it. Unlike other manufacturers, Serta’s individually wrapped coil mattresses use advanced twice-tempered steel for additional durability. Tempering is the process of heating and cooling the coils to ensure they retain their proper shape over time. A “double heat tempered” coil has gone through that process twice, ensuring increased durability.
• Continuous coil mattresses have rows of advanced coils made of a single continuous wire. By sharing the weight load across several innersprings, each spring holds its share and integrity longer. This results in a system that is stronger and more supportive than other innerspring systems. Serta uses continuous coil in our Continuous Support® Innerspring and our Free Flex® Innerspring.
You might have heard a rumor that the more coils in an innerspring, the more supportive the mattress will be. While this can be true, coil count is not nearly as critical today as it once was. These days, the combination of coil count, coil gauge and the construction of the coils is a much more important factor in determining the overall comfort and support of the mattress. For example, Serta’s continuous coil innerspring systems can provide greater support than other coil systems with similar coil counts because of the unique construction.