Date : 2021-05-10 13:31:49

A Definitive Guide: How Is Foam Density Measured in Mattresses?

When you look for a mattress, you always look for the support, comfort and plushness, the type, and manufacturer, but most people overlook one crucial factor. That is, mattress foam density is one of the most important factors influencing its support, comfort and plushness, response rate, and longevity. As a direct measure of the quality of your mattress, foam density for a mattress a critical factor in manufacturing mattresses that work for your body. Before understanding how foam impacts your mattress's quality assessment and your sleep, among other factors, let's look at a scientific explanation.

Measuring foam density and meaning of different foam units and indicators in a mattress:
Before we jump into the technical details later in this foam density guide, we need to understand how it is measured. Mattress foam density is the weight of one cubic foot of a particular type divided by its volume. So, a high-density memory foam or high-density polyfoam would have a higher mass per cubic weight than a lower density option. In simple terms, it has more foam packed into the same space, and as a result, is denser and enjoys other qualities than a low-density variant. For example, you may come across a choice between a 32-density foam vs. a 40 density one and might not be aware of what to choose. That is where our mattress density guide comes in and tells you which density is better for you.

Also, the same density of different mattress foam materials would vary by the comfort and support they provide you. A 40 density would be high density in polyfoam (PU Foam), not so much in memory foam, and very low for others. For example, in the Indian demographic, people prefer the PU Foam to have a density value between 32 and 40. Similarly, memory foam should have a density value between 50-60 and between 55-65 for latex foam. These values change depending upon the manufacturer and can be an indicator of quality, the type of softness, and support from the mattress. Higher values of density like 90 and 100 are used in ortho cores or support layer or the ortho core of a given mattress.

Mattress foam density guide and Foam Density Chart for Mattresses:
With so many density variations and different layers needing different kinds of density, how do you know what you're getting is right for your body?

The density values are shown above for different mattress types give a rough idea of what you should be looking for in terms of density. But your bodyweight, preference, and other factors matter just as much in deciding on a compatible mattress. You can use our SleepID algorithm for the best mattress compatibility and the best densities chosen for different layers. However, if you're looking for a bespoke or hospitality mattress as per customer input, the foam density chart beneath can help:

  • PU Foam density: PU foam is a generally low-density material with larger pores and lies between the 32 and 40 density range. To be specific, a 1.5lbs/cubic foot PU foam would weigh approx. 680 grams. At the same time, high-density polyfoam would have a density unit of 1.8lbs/cubic foot and weigh about 135 grams more at 816 grams for the same block size. These measurements are essential in assessing your fit for the mattress and the use that the layer is intended for. For example, PU foam layers between the thick layers of a high-density mattress would be thin and low-density. Whereas, to ensure high-quality comfort and heat insulation, the higher density variant of the PU foam would feel better in the comfort layer. Additionally, using high-density polyfoam layers in your mattress also ensures better support, and a medium-firm polyfoam layer would be ideal for most. PU foam isn't the best material to rely on for support, and you can check the below charts for mattress density and bodyweight comparisons.

    Low Density: Less than 1.5 pounds per cubic foot.
    Medium Density: Between 1.5 to 1.7 pounds per cubic foot.
    High Density: Greater than 1.7 pounds per cubic foot.
  • Memory foam density: Memory foam is denser than PU foam, and higher density means smaller pores, more heat, and decreasing suitability for obese or overweight individuals. That is why we also need to assess the suitability as per bodyweight for high-density memory foam when using in a mattress. Memory foam should have a density value between 40-50, and the greater the density, the more comfortable, supportive, and prone to overheating (less suitability for overweight or excessive sweating people) it becomes. Additionally, memory foam's cost is also more than PU foam and can increase significantly depending upon the density used. Where lower-density memory foam would be suitable (medium-firm) for most people and be less durable, high-density memory foam mattress is excellent for pain relief and comfort, especially if it regulates temperature mattress construction.
    1. Medium-firm memory foam: Medium-firm memory foam would lie in the range of 3.5-4 pounds per cubic foot or weigh between 1.59 - 1.8 kg per cubic foot. It is significantly heavier than PU foam but maintains its form and benefits longer than lower density foam and suitable for people with average or perfect BMI.
    2. High-density memory foam: High-density memory foam, on the other hand, would have a density of 6 pounds per cubic foot, and weigh north of 2.7 kg per cubic foot, making it more suitable for support layer in any mattress. This would be a good option for people looking to rely on a pure high-density mattress, and people with slightly higher or perfect BMI would enjoy sleeping on it. High-density memory foam may be used in different thicknesses in memory foam or orthopedic mattresses for body contouring and pressure relief. It is not a good option to use high-density memory foam in the comfort layer of any mattress. It would lead to excessive heating and an uncomfortable stuck-in-bed sleeping experience.

      Memory foam density:
      Low density: Less than 3.5 pounds per cubic foot
      Medium-firm (medium-density): Between 3.5-4 pounds per cubic foot
      High Density: Greater than 6 pounds per cubic foot

      High-density memory foam has several pros and cons and isn't the best option for the wider population. As mentioned, it is best used in the support layer as a thicker layer that contours the body and offers excellent support for a pure memory foam mattress. Whereas, it is a good idea to use a medium-firm memory foam mattress in comfort layer or support layer depending upon mattress and bodyweight support requirement.
  • Organic latex foam density: Organic latex foam is one of the best foam materials one can use in different hybrid or pure latex foam mattresses. Although manufacturers may use synthetic latex foam, we're going to be talking about 100% pure and organic latex foam. Although synthetic mattress properties and benefits vary, pure organic latex foam mattress has a density depending upon the type. Dunlop latex foam is the more durable and high-density variant, and the Talalay is slightly less dense but maintains all the properties.

    Latex foam is medium-firm in nature, and its density can be configured depending upon use. For example, using Talalay latex foam in most mattresses' comfort layer may be possible. In contrast, Dunlop latex foam is strictly meant for the support layer. Latex foam would have a density higher than 3.75 pounds per cubic foot. Talalay latex foam would lie in the 3.75- 6 pounds per cubic feet range, and Dunlop would be denser and lie out of this range. Most people would find a medium-firm or high-density Talalay latex foam variant between the 3.75-6 pounds per cubic feet range. Dunlop latex foam price would be lower, and Talalay sleep-grade organic latex foam mattress price would be on the higher side. As a result, only up to 2-4 inches of Talalay foam is used in any latex or hybrid mattress.

    Latex foam density:
    Low density: Lower than 3.75 pounds per cubic feet
    Medium-firm (Medium-density): Between 3.75 and 6 cubic feet
    High-density (Only in Dunlop): Above 6 pounds per cubic feet

Why high-quality raw materials matter?
High-quality raw materials in your mattress are essential in ensuring long-term comfort, and when it comes to foam, it takes new meaning. High-quality raw materials are essential in the sleep industry because of the nature of the product (be it mattresses, pillows, or even the mattress fabric). People have varying sleep patterns and different climates in a country as vast as India. Because of this, some climates can be colder, and some can be hot and humid or even dry. Keeping the demographics in mind, how people also sleep changes, and raw materials impact the sleep environment and ultimately your sleep quality.

Because your mattress is your primary personal care item and responsible for long-term physiological health, better the quality, more significant the benefits. For example, higher quality raw materials in fabric and foam ensure no sanitation and quality issues down the line. For example, higher quality raw materials are especially beneficial in using rebonded foam, as some manufacturers may use recycled shreds. This recycling leads to off-gassing and health hazards, in addition to inconsistent quality in products.

In contrast, in-house manufactured new shreds would be a better choice for the same rebonded foam. Moreover, when we talk about raw foam quality, the quality is a measure of density and the manufacturing process (addition or absence of chemicals). So, high-quality raw materials are essential because of how it feels and works in the long-term and aesthetic benefits.

Why does foam density matter?
Foam density is very important in your mattress because of how density functions differently under different mattress layers. So, even though different foam densities have a variable density value, their density also plays a different role in the different mattress layers. For example, the high-density foam would help increase comfort, plushness, and overall durability in the comfort layer.

However, depending upon the type of foam we use in different layers, density variation can lead to a different experience in different mattresses. Using higher density foam in the support layer helps offer contouring support that isn't possible by making the layer softer. The same principle also applies to the core of the mattress, where ultra-high-density foam works to provide support to the upper layers or either side of a dual-comfort mattress.

Advantages of high-density foam:
High-density foam is a great option and parameter of better quality in a mattress. But how does high-density foam impact your sleep and mattress quality? Is low-density mattress foam going to be harmful or worse? You can find these answers in the foam density guide below:

  • Durability: After some time most, mattresses start showing signs of aging or having slept in. It might be too subtle to notice or visible to look from a distance. High-density foam plays a massive role in the way your mattress works in the long run. High-density foam has smaller pores and greater durability than low-density options because of mattress mechanics and general use.
    The high-density foam also lasts longer because of less invasive environmental impact as dust, allergens, and moisture don't diversely impact the layers to cause short-term damage. This property is also helpful in ensuring your mattress maintenance doesn't lead to erosion of superficial or internal layers. Moreover, high-density foam is also less prone to wear and tear, abrasion than low-density mattresses.

    Additionally, high-density foam layers also last long because your mattress support and comfort you without taking the physical damage itself. So, as an overweight person using a high-density organic latex foam mattress than compared to a low-density variant, the mattress would stand more chances of developing body impression. A low-density organic latex foam wouldn't be as hypoallergenic, supportive, and comfortable as a high-density option.
  • More comfortable: When we talk of comfort, our mind associates it with softness. However, softness doesn't necessarily mean that your foam mattress needs to be low-density. On the contrary, the higher your mattress foam density is, the more comfortable it will be for your body in the short and long term. This is because high-density layers have a higher response rate and pressure-relieving properties that lower-density mattress foam variants do not have.
    Comfort means that you feel pressure relief and a certain degree of softness cushioning your body's curves. However, lower-density options wouldn't be as effective in being comfortable for your muscles or allow you to feel as comfortable as a high-density option. A low-density foam layer would melt or give more freedom to your body weight without much reactive pressure and ultimately rely on layers beneath it. This is why a high-density layer in the comfort layer is better for body pain relief in the short term and allows you to feel more at peace than a low-density foam layer.

    If you're looking for a relatively softer luxury mattress and don't share an affinity for a firmer mattress surface, a medium-density memory foam layer would be perfect. But when we talk about memory foam as a perfect example of a differentiator between low-density and high-density options, we should also consider how it reacts with your body weight. For example, a medium-density memory foam layer would be better for use in most mattresses as it wouldn't insulate heat as efficiently as a high-density variant. Moreover, a medium-density memory foam layer would also offer more leeway in tossing and turning without feeling stuck. But this is because of memory foam's pressure-relieving and body contouring properties.

    The same scenario doesn't apply to an organic latex foam or HR foam layer, as the denser they are, the better. Your mattress should keep you afloat (at least partially, as in a high-density memory foam mattress). Comfort is subjective based on body weight and how the high-density comfort layer reacts with your body and can vary depending upon the type of mattress mentioned above.
  • Supportive: A high-density mattress foam layer is crucial in enhancing the support of your mattress's overall functioning. While the core may be ultra-high- or high-density foam to ensure long life and acting as the sole support for years, it is also essential in other layers. High-density foam present in both the support and comfort layers is critical in enhancing how your spine and muscles feel.

    It would help if you had support for spinal alignment and when you sleep in different positions, and a high-density foam layered mattress is a better option than a lower one. This is because when you sleep on your back, sides, different parts of your body need support and cushioning to be comfortable. For example, sleeping on your side puts maximum pressure on your shoulder blade muscles, needs neck orientation with a pillow, and exerts pressure on your pelvic area. To address this, you need adequate comfort and support on your pressure points, without which it leads to pain in the morning.
    If you sleep on a low-density mattress with a robust support system at the base, it will lead to pains in both the short and long term. However, sleeping in different positions on a high-density layer provides adequate support and reactive pressure that keeps your pressure points afloat and comfortable.

    The supportive factor in a high-density foam layer doesn't mean that your mattress feels like a brick or doesn't offer any freedom of movement in sleep. You get support in all the right pressure points with adequate comfort, which isn't an option in a lower-density foam mattress. The durability and support of a high-density mattress help you sleep for years in your favorite position without waking up in awkward morning pains or chronic pains.
  • Pressure-relieving: High-density foam has the essential role of acting as the primary pressure-relieving layer of your mattress. Your mattress core or base with the ortho foam layer or innerspring layer does help relieve pressure in your muscles. But your primary pressure reliever when you go to sleep on your mattress is its comfort and support layers acting together. Pressure relief in your body results from your muscles being able to relax and destress after a day and relaxing in a neutral position where the reactive pressure cancels their physical stress. This reactive pressure that neutralizes the discomfort or pending stress in your muscles, joints, and throughout the body cancels out with the help of a high-density foam layer.

    For example, when you go to bed on a high-density memory foam mattress, the high-density comfort layer helps relieve pressure. It comforts your skin and underlying tissues and muscles. The high-density support layer in the mattress could be HR foam, latex foam, or even memory foam that contours your body and helps support it in different positions. As a result, you end up with a sleeping experience that cancels your muscle pressure and even results in pain relief.
  • Pain-relief: Pain-relief is an essential property in a mattress, irrespective of its intent as an orthopedic mattress or not. High-density mattress foam is critical for pain relief in addition to a robust support system. This is because while the innerspring core or the ortho foam core would provide full-body support to your body, there is more to keeping your body in proper support than the core. So, when you look at a mattress for its pain-relieving properties, the support and comfort layers also need to be high-density because they add to the support that your mattress core provides.
    At night, in addition to pressure relief, your muscles need to relax in a neutral position to feel pain-free and get relief from chronic pain. Your posture and how you sleep in different positions with a high-density foam layer offering support and pressure relief is essential. Sleeping on your side or back needs your spine to relax in its natural shape, and the same principle applies to your entire body.

    Your innerspring or ortho foam core may provide different levels of support, but it is your high-density support layer that works to relieve pain by contouring your body. Your spine and muscles rest in a position that the high-density support layer orients them in, and you get to experience blissful, pain-free sleep.

    On the contrary, lower density mattress variants wouldn't be as effective in pain relief, as your body weight (however average or higher) would always tend to sink lower without reactive pressure. That is why most orthopedic mattresses have a medium-density memory foam layer as the comfort, and the surface firmness only increases.

    In orthopedic innerspring or dual-comfort mattresses, high-density polyfoam or high-density organic latex foam plays a critical role. Your mattress can have a Bonnell spring system, but it still needs a firm high-density layer to relieve pressure and offer full-body support. Without a proper high-density layer, sleeping on a Bonnell coil or any pocket coil mattress would be impossible as the spring system would 'pinch' your body.
  • Enhanced sleep quality: Your mattress's density influences how comfortable you feel when you go to sleep. As discussed above, it is responsible for pressure relief, pain-free sleeping, and even support. All these factors together make it possible to sleep better, and a low-density option wouldn't be as effective or durable.
    You can enjoy high-quality sleep when you're comfortable, supported and feel no pressure or discomfort in any part of your body. Although different parts play their role, and high-quality foam layers aren't responsible for the significant support, pain-relief, pressure-relief, and other advantages, you need all of them together.

    Without high-density foam layers in place, your mattress experience wouldn't make the best use of all the benefits your body can enjoy. Your sleep quality relies on different factors like sleep environment, mattress temperature, pressure, and pain-relieving properties, and even support. In a high-density foam mattress, you can rest assured with all these factors working in your favor in a compatible mattress. However, a low-density mattress foam layer wouldn't be able to offer all these benefits in one package.

Relationship between high-density, firmness, and comfort:
When we talk of any given mattress layer or type of foam density, the high-density brings different pros and cons. Moreover, the mattress foam density also has a minimum requirement for the body weight it would be comfortable. For example, overweight or obese person would need adequate support from an ortho core or innerspring system and provide adequate cushioning. High-density memory foam would be suitable for a person with average body weight but not a good option for an overweight or obese person or anyone who sweats excessively. Similarly, relying on a high-density variant of latex foam wouldn't always be a good factor when your bodyweight or specific requirements fall in the average or perfect BMI range.

To address the mattress firmness and density issue, we need to look at the type of mattress we're talking about. For example, a medium-firm or even high-density memory foam layer would feel comfortable and plush, and firm latex foam, HR foam, or rebonded foam would be too hard to use in the comfort layer. So, mattress density doesn't determine how it feels but plays a significant role in the sleeping experience in the comfort layer. Taking the same case in mind, ultra-high density or high-density options of HR foam, rebonded foam, or latex foam are only suitable for use in the support layer and unusable/ non-viable in the comfort layer.

High-density mattresses share several benefits and pose problems for people who don't choose their mattresses carefully. Issues from a high-density mattress can be similar to:

  • Excessive body heat: High-density memory foam wouldn't be ideal for people with higher body weight and living in hot and humid climates. Irrespective of one's preference for memory foam's sinking or soft and plush sleeping experience, you should always go for the suitable mattress foam layers for your body. High-density memory foam can lead to excessive sweating, discomfort, and an unpleasant sleeping experience when tossing and turning in sleep.
  • Inability to sleep: Different types of mattresses use different densities of materials in their layers. Higher-density layers like PU Foam are only suitable for use in the comfort layer. High-density HR foam, organic latex foam, and other denser materials are only good for support layers. Having the proper density in the right place is just as important, and improper installation or choosing can cause the inability to sleep.
    Difficulty sleeping can be because of excessive body heat, inadequate firmness, excessive firmness, and incompatibility with your mattress type. That is why choosing the proper density in a hotel, or bespoke mattress is critical. When guests stay at your hotel, they prefer a certain degree of comfort and pleasure, and using high-density layers all around wouldn't lead to high satisfaction rates. High-density is essential, but it is also essential to have the right mattress type, which is more likely in domestic use.
  • Inadequate plushness: As mentioned above, high-density doesn't always mean a firmer mattress. If you're going for a softer mattress, you still need a specific density and plushness in it, especially in the comfort layer. That is why a high-density memory foam or PU foam is usually installed in the comfort layer. Any other materials or lower density of these two foam types can lead to inadequate plushness. The mattress would be soft, but plushness and comfort are different, especially when talking about high-density mattresses.

Choosing the correct density and mattress:
The density numbers can be a bit technical for most to look into and order custom mattresses. That is why most of our luxury mattresses use the proper density in different layers and have high-density comfort and support layers in all the right places. If you're looking to order custom or bespoke mattresses for your hotel or home, this mattress density guide can prove beneficial. Alternatively, use our SleepID tool and mattress brochures to assess the kind of density we use in our mattresses and how it would work for your body. SleepID pairs you with the best mattress for your body type, letting us worry about the right density based on years of real-world demographic specific research.