Measured: Mattresses are named for what carries the load, coils, foam, latex or a coil and foam hybrid. Coil counts are quoted for a queen, and foam is quoted by density in pounds per cubic foot.
The basics
What to know about mattress construction
Construction is what firmness is made of. Two beds both labeled medium behave completely differently. What matters is whether steel, foam, rubber or a stack of both carries your weight. Construction decides motion transfer, heat, edge strength and how long the bed keeps its shape.
Read a mattress as two parts. The support core is the bottom two thirds and carries the load; the comfort layer is the padding above it and sets the feel. Coil counts describe the core, though beyond roughly 800 pocketed coils in a queen the extra springs add little you can feel. Foam is described by density, and higher density resists sagging longer. Height is the other number: most quality beds run 10 to 14 inches deep, and anything over 14 needs deep-pocket sheets.
Compare the four against your actual complaints. If you sleep hot, coils and latex move air while dense memory foam holds it. If a partner's movement wakes you, foam absorbs it and open coils pass it along. If you sit on the edge to put shoes on, coils hold that edge best. Expect 7 to 10 years from a good bed of any construction here, and longer from latex.
