When buying any product – especially high priced products – it is very important for the consumer to do their homework before forking over their hard-earned dollars. There is a feature of mattresses that every manufacturer promotes that is not for the benefit of the consumer but is a great benefit to them. That feature is the foam-encasement feature. For those of you who are not familiar with this feature, it is the three or four inch wide foam boarder that encases the innerspring unit of a mattress. Manufacturers promote this as a feature that expands the sleep surface and firms the edge of a mattress. This is complete nonsense!
To prove the point, we are going to use the warranty of two prominent mattress manufacturers, Dormia and Tempur-Pedic. In case you don't know both Dormia memory foam and Tempur-Pedic mattresses are made of 100% polyurethane foam. Polyurethane foam is made from petroleum so it is essentially plastic foam. The Tempur-Pedic warranty states: “It is understood that this limited warranty does not include a normal increase in softness of the Tempur pressure-relieving material.” So Tempur-Pedic admits that their all-polyurethane foam mattresses soften and, by-the-way, it isn't covered under the warranty. Dormia is no different. Their warranty states: “It is understood that this does not include a normal increase of softness in the foam.” So both manufacturers of all polyurethane foam mattresses admit that poly softens.
The foam that innerspring mattress manufacturers use to foam encase their mattresses is polyurethane. Therefore, judging by the warranties of the above referenced manufacturers, the foam encasement foam will soften also. If you sit on the edge of your mattress when you wake in the morning and to put on your shoes, this firm sitting edge will soften and turn into a soft sitting edge and become softer than the innerspring unit in the middle thus also changing the sleep surface at the edge.
The real reason for foam encasement is that it saves the manufacturer lots of money. Plastic foam is much less expensive than spring steel. Foam encasing a mattress reduces the amount of spring steel used by eighteen percent. Then it gives the manufacturer a marketing ploy (marketing spin) to promote their mattresses and to convince the customer to pay more money for the extra feature. Manufacturers of latex and memory foam mattresses also employ this tactic. Please read our other articles and learn the many other crafty things mattress manufacturers do to rip off their customers!