Foam Density, Weight, Firmness and Usability


How to measure foam density? Foam density is measured in kilograms per cubic meter. This unit of measurement is important: foam density defines what is the use of the material.

Polyethylene and polyurethane foam density depends on the manufacturing process. The foam density scale ranges from 24 kg/m3 up to 300 kg/m3.

What is the density of foam?

Shortly, the density of the foam means the mass of the foam that is measurable in one specific size. Density and weight are now always directly proportional to the firmness of the material. Mostly it’s true that higher density foams that weigh more are firmer (more unyielding when pressed), but there are exceptions too.

Is foam weight important?

Therefore, foam weight is not that important, because it applies to the whole product. The density and the firmness are much more important metrics. Firmness is like a foam compression rate, and it’s good to know how durable foam is if it’s used for insulation.

There is a big difference between linear and cross-linked foam types.

Linear foam’s average density is between 24-25 kg/m3, while cross-linked foam types’ density can be above 200 kg/m3.

The use of low-density and high-density foams

In the following, we will compare the density of cross-linked foams, made in Trocellen factories.

Foam density in the sport industry

Low-density foam mattresses are in widespread use in freetime activities and the sports industry. 30kg/m3 mattresses are used as

  • Beach mattress
  • Backpacking mattress
  • Aqua-fitness mattress (because the cross-linked foams are waterproof)

Regular-density foam type is also used as

  • Yoga mattresses. 50-60 kg/m3 density is expected with great firmness, otherwise while doing yoga, our limbs would sink in the foam.
  • For combat sports (such as wrestling) high stability foam is needed with 90 kg/m3 density.
  • But for ground-fighting, a low-density, soft 30 kg/m3 foam is also required to soften the fall.

Packaging foam density

Low-density foams are used for ‘one-time delivery’ packages. The food industry uses this the most.

Heavy foams (around 90 kg/m3) are also used when it comes to packaging mechanics. The car industry and other heavy-industry companies are using this because high-density foams are more durable and can be used more than once, therefore it’s more economically friendly.

Foam insulation

Low and regular density foam with high firmness abilities is used in the building industry mainly for insulation.

30 kg/m3 is the most common material in use. It is generally true that the softer the foam, the more soundproof it is. And if it’s thicker it will have better thermal insulation.

On the other hand, under the floor, a 90 kg/m3 density foam is recommended because it can reduce the echo of the room.

Upholstery & couch cushions

Upholstery and couch cushion foams are also mostly high-density foams. Duration is extremely important for cushions, so its density can be above 80 kg/m3. Seats and memory foam blocks are also high-density foams.