Polyurethane foam has been used as both a comfort layer and solid support core in mattresses since the late 1950s, when it was first touted as a “space age” material that could be made at different levels of firmness to vary the feel of a mattress.
Today, most people still sleep on a mattress that contains at least a small amount of polyurethane foam, whether it’s a conventional innerspring model or a specialty mattress made with memory foam or latex. Poly foam is a versatile and affordable mattress material, with applications ranging from constructions where the foam provides both comfort and support, to more targeted uses, where the material is used to create a low-cost support base for more expensive layers of memory foam and latex, or as an additional comfort layer.
One of the biggest benefits of polyurethane foam is its ability to resist body impressions— the compression that takes place over time due to your body’s weight. By adding the right amount and firmness of foam in strategic areas and layers, poly foam mattresses can be designed to resist body impressions and last longer.
Another benefit of quality poly foam as a comfort layer is that while it may compact a little bit right after you start sleeping on your new mattress, it doesn’t tend to change much after that. This characteristic can help protect the materials used in the lower levels of the bed from compacting as they otherwise might.
Polyurethane foam has a higher chemical content than natural materials such as latex. But, in addition to its lower price tag, poly foam has the benefit of being noiseless and dustless, and it resists crumbling. In addition, the material features an open cell structure that lets it breathe, reducing the chance of mold and mildew.
When shopping for mattresses, keep in mind that not all polyurethane foams are equal. Some foams offer more support, a greater resistance to compaction and a better feel. In general, higher density foams will last longer, feel firmer, and provide more support. They also carry a higher price tag.