Foam mattresses are typically made of high-density foam or memory foam and serve as the main support layer. It supports body weight, maintains the natural curve of the spine, and prevents excessive sagging in certain areas. High-density foam provides stronger support and durability, while memory foam conforms to the body's contours based on temperature and weight, enhancing comfort. Above the core layer, foam mattresses usually have one or more layers of soft material as a comfort layer. This layer may use low-density foam, latex, or memory foam, and its purpose is to enhance the mattress's softness and conformability while cushioning pressure points for a more comfortable sleep. The thickness and material choice of the comfort layer directly affect the mattress's feel and the overall sleep experience.
The outermost layer of the mattress is usually covered with a breathable, soft, and durable fabric, and may include a dust- or water-resistant protective layer. This fabric layer not only improves the feel but also protects the internal foam from dust, sweat, or moisture. Some high-end mattresses also use quilting to tightly secure the comfort layer to the fabric, maintaining structural stability and increasing durability and aesthetics.