Innerspring Mattress Information

Coil Count

• Most mattresses have about 300 to 800 coils, depending on the size and construction of the mattress. According to Dr. Leona Hawks of Utah State University, a full-size mattress should have 300 coils, a queen about 400 coils, and a king about 480 coils. Mattresses with fewer coils may use a heavier gauge wire for support, while some manufacturers may use a higher number of thinner coils to give a mattress softer support. Many people think the number of coils makes the mattress more comfortable; the real key is the construction and design of the coils.

Coil Construction

• Coils tempered with heat or electricity return to their original shape after being compressed. Some mattress companies apply an enamel or plastic coating so that the coils won't corrode quickly. Generally the thicker the wire, the firmer the support of the mattress. Manufacturers of the best quality mattresses typically use a 13-gauge wire. Keep in mind that the higher the gauge of the wire, the thinner the wire is. Still, depending on the design of the coils, one made of thinner, 18-gauge wire can still be of good quality.

Coil Design

• Of the three major designs of coils used in innerspring mattresses, manufacturers most often choose to use hourglass-shaped coils. Small corkscrew shaped wires may stabilize the hourglass-shaped wires to keep them from moving from side to side when compressed. Another design in springs, individually wrapped pocketed coils, move independently of each other. If you sleep with a partner, you may prefer this kind of mattress because it reduces the amount of movement you feel when sharing the bed. Continuous coils, the strongest design, use more coils than the others, and connect to each other through a series of s-shaped ringlets.

Upholstery

• Insulation covers the coil system of an innerspring mattress and keeps the upholstery material from becoming entangled in the coils. Products often used include sisal, synthetic pads and fibers, and polypropylene netting. Cotton batting or urethane foam covers the insulation. Some mattress manufacturers use extra layers of foam or upholstery to change the firmness of the bed. Some innerspring mattresses come with an additional pillow top to make the bed more comfortable.

Considerations

• Choose a good quality foundation for your innerspring mattress since the foundation accounts for one third of the support of the bed. Ensure the foundation has sufficient padding. When you run you hand over the cover of the foundation, it should feel soft. An innerspring mattress will carry a warranty that covers materials and workmanship. You may consider purchasing the matching foundation, since some manufacturers will void the warranty on the mattress if you don't.