It can be confusing when selecting foam as to what is meant by density. It is tempting to assume that density is related to how firm the foam is, but this isn’t the case. High density foam can be soft. So, what is meant when we describe foam as being of high density? The density of foam is about its strength. The denser the foam is, the more supportive it will be, though at the same time it isn’t a measure of comfort. In essence, density in foam affects how it feels and how it will perform.
How is high density foam measured?
The density of all foam is calculated using its weight in pounds and volume in cubic feet. Volume is found by multiplying height x length x width. The weight of the foam is then divided by the volume. This gives a figure in pounds per cubic feet. You may see this on foam as PCF. Foam density can vary widely from around 1.5PCF to over 6PCF. Higher numbers indicate a high-density foam.
How is foam made to different densities
Foam manufacturers use what are known as blowing agents and additives to expand the foam. Different compositions of agents and additives effect the foam’s density and cell structure. These varying structures affect how the foam will perform. Generally, low density foam will have a more open cell structure, high density foam will have a smaller, more compact cell structure, so it feels firm and can withstand more pressure.
Why density and firmness are not the same
Foam density is a separate measurement to foam firmness. Firmness is about how the foam reacts when pressed. This is measured by how much weight is needed to squash foam down to 25% of its thickness. You may see this on foam as IDF, Indentation Load Deflection. Firmness usually comes down to personal preference. When choosing foam, you should consider firmness for comfort and density for added durability.
How do I know which is high density foam?
A good foam supplier, like F.C. Hancox, will be able to advise on the density of their foam products and the uses for which they are ideal. You can also look for or ask to see the properties of a foam you are intending to buy and check the PCF rating.
What are some uses?
Memory foams and reflex foams are good examples of high-density foam. There are many uses, and they make ideal foams for mattresses, seating, and cushions. They are excellent where support is needed, so good examples are wheelchairs, medical cushions, and mattresses due to having supportive qualities. High density foams can take more weight and are less likely to sag.
Are there any disadvantages?
Probably the biggest consideration for the consumer is that high density foams tend to be more expensive than low density. This is due to more materials being needed during manufacture. It does however have the advantage of being longer lasting, so could be cost effective in the long run.
High density foam is a great choice of foam for a wide range of applications. F.C. Hancox has Vasco memory foam and a range of reflex foams that are high density and are available through our foam cut to size service. Our staff are only too happy to chat about the properties of our foams, including density, so whatever your needs simply get in touch.
