Different Types of Cushion Foam

Open Cell or Closed Cell Foam

• An open cell foam structure is made of cells that allow air through the material, which makes it soft and springy. Open cell foam is used in most interior upholstery cushions. A closed cell foam structure has holes that are contained in rigid walls so air will not pass through, making the foam waterproof. It is found in flotation devices. Another good setting for closed cell foam is outdoor cushions, such as boat seating. Compared to open cell foam, it is dense, firm and usually more expensive.

Polyurethane Foam

• Polyurethane is a common foam material used for cushions. The comfort and durability of polyurethane cushions is partially based on standard tests performed. The high resiliency rating (HR) gives an indication of how resilient the foam is; the density rating is the amount of foam found in a standard set of dimensions; and the Indentation Force Deflection (IFD) value is a measure of how many pounds are needed to indent a foam sample by 25 percent. Another thing that comes into play is the chair itself. It is best to test cushions out before buying them.

Memory Foam

• Memory or viscose elastic foam is a type of open cell polyurethane foam developed by a Swedish company for NASA. It has less spring than an ordinary foam cushion and takes time to bounce back to its original state. Memory foam is harder to cut into cushion shapes because of its slow recovery. The IFD and density standards used to measure regular polyurethane foam are harder to rely on when judging memory foam because of these properties, so the variety available in the market may range in softness or firmness.

Latex Foam

• The latex foam process begins with whipping the liquid rubber to make bubbles. It then undergoes a process to allow it to set in a mold. Latex comes in both synthetic and natural form. The natural rubber is more expensive. Latex cushions are denser than polyurethane. The benefit of latex is the support as well as the fact that it is antimicrobial, anti fungal and waterproof.