Refer a Friend, Get up to $50

FREE Shipping & 0% Financing Available

Ends in

Our ULTIMATE Foam Mattress Guide!
Make a selection
Make a selection
Man Sitting on Polysleep Foam Mattress


Our ULTIMATE Foam Mattress Guide!

Double Chevron Left Back to News

Buying your next foam mattress keeps you awake at night?

We know how complicated this decision can be!

With such a wide selection of foams, brands and retailers... it can be difficult to find your way around...

But don't worry, you’re now in good hands!

As hybrid foam mattresses specialists, we’ve decided to help you.

Through this guide, we’ll define the different types of foam, and help you understand what constitutes a good mattress.

At the end of this article, you’ll be able to easily choose the ideal foam mattress for your needs...

To know everything about foam mattresses, read on!

A woman drinks tea on her Polysleep foam mattress while browsing the computer

Support, firmness and density: a few definitions to start

Before getting to the heart of the matter, here are a few concepts that will help you in your quest for the perfect foam mattress.


This is the ability of a mattress, whether made of foam or not, to properly support your body so that your spine is perfectly aligned.

Good support helps prevent the muscle and joint pain that can interfere with your sleep. So, optimal support allows for better recovery during the night!


Firmness is subjective. It’s the feel of the mattress when you lie on it.

There’s no pre-established standard for measuring firmness. It depends on you! This is why Polysleep has established its own firmness index, on a scale ranging from 1 to 10, from very soft to very firm.

You can discover how this index works in our comparative articles on foam mattresses!

The point to remember is the following:

A mattress with the same build can appear more or less firm from one person to another.

But why? What are the factors that influence the firmness of a mattress?

Let's look at an example to illustrate this concept:

A person weighing 240 lb who sleeps on their back may find that a "soft" mattress does not provide enough support for their body because it sags excessively.

On the contrary, a side sleeper weighing less than 130 pounds might find that this same mattress provides optimal support for their body shape.

So, depending on your weight, your height and your morphology, your feeling will be different from that of your bed partner, for the same mattress.

In addition, other factors play a role in the feeling of firmness: manufacturing methods and materials.

These factors also influence the support and durability of the mattress.

For example, the Polysleep, Origin and Zephyr mattress models all use viscoelastic hybrid foam, as well as several layers of polyurethane foam.

Although the materials are the same, it is the manufacturing methods of the different foam layers that determine the quality of each mattress.

Throughout the creation process, the Polysleep teams have combined ingenuity and practicality in order to offer the best of all worlds in terms of support, comfort, durability and price.

To conclude, it’s important to distinguish the concept of firmness from the concept of support, which are totally independent.


The concept of foam density is simple to explain:

It is the weight per cubic foot of a layer of foam. It's measured in pounds.

So, the unit used for the density of a foam is “lb/ft³” (pounds per cubic foot).

Hence, if you read "density of 3 lb/ft³" for a foam mattress, it means that a cube of 12″ x 12″ x 12″ of this foam weighs 3 pounds.

A first distinction between foams is therefore possible according to density.

The Polysleep mattress located in a trailer

There are three types:

  1. Low density foams (< 4 lb/ft³ for memory foam and < 1.5 lb/ft³ for polyurethane foam). Mattresses containing these foams:

  • Are usually less expensive,

  • Have necessarily less longevity, due to their lower density (faster softening, and risk of premature sagging),

  • Also provide less support. As a result, they are unsuitable for sleepers with chronic pain.


  1. Medium density foams (4 to 5 lb/ft³ for memory foam and 1.5 to 1.8 lb/ft³ for polyurethane foam). Mattresses made of these foams are generally more expensive. However, you will get your money's worth because:

  • Their longevity is much greater,

  • The support is also much better,

  • Considering the two points mentioned above, even if you pay more, the quality/price ratio is much better than low density foam mattresses.

  1. High density foams (≥ 5 lb/ft³ for memory foam and > 1.8 lb/ft³ for polyurethane foam). Models using this type of foam:

  • Provide maximum longevity,

  • Offer outstanding support, especially at pressure points,

  • Are heavier to carry,

  • Are, however, much more expensive.

 Girl jumping on her Polysleep mattress

Please note that polyurethane foam and memory foam are two completely different materials.

Since their composition is not the same, the density measurement differs when they are compared on an equal footing:

Low Density

Medium Density

High Density

Polyurethane foam

< 1.5 lb/ft³

1.5–1.8 lb/ft³

> 1.8 lb/ft³

Memory foam

< 4 lb/ft³

4–5 lb/ft³

> 5 lb/ft³

Reminder: Polysleep mattresses are not made of memory foam!

Moreover, they are only made of medium to high density foam, depending on the different layers and their location in the mattress.

Density vs. Firmness:

Although density affects the durability, the quality of sleep and the price of a mattress, it doesn’t necessarily affect the firmness!

Just because a mattress is made of high density foam doesn’t necessarily mean that it will be firm. And conversely, a low density mattress is not always soft.


It's very simple! Density is related to the quantity of foam in the mattress, while firmness is related to your weight and its distribution on the mattress (pressure surface).

Both concepts are therefore influenced by completely independent variables!

The Different Foam Mattress Options:

Polyether foam mattresses

Polyether foam mattresses offer as their main feature a firm sleep, perfect for people of large size.

However, the foam in these mattresses has difficulty withstanding humidity, and their comfort can be rather Spartan, especially in terms of ventilation. To be sure, these are mattresses made of small, closed cells: the air won’t circulate well so the mattress will store heat!

In addition, their durability is limited over time. So, polyether foam mattresses, considered entry-range, won’t keep up if you want to use them on a daily basis. Reserve them as extra beds in your second home.

Polyurethane foam mattresses

Polyurethane foam mattresses offer a good balance in terms of support and antibacterial and antifungal capabilities, while being hypoallergenic.

In addition, they offer a wide choice in terms of support and comfort, thanks to the multiple densities of foam available, and the different comfort zones of individuals.

Also, this type of foam being made with an open-cell structure, like the one used by Polysleep (CertiPUR-US polyurethane foam), allows for better air circulation, and so better evacuation of body heat. No more hot and sweaty nights!

Generally, these foams feature medium to high density.

So, classic polyurethane foam mattresses are more durable and offer a high level of support that will last over time!

Memory foam or viscoelastic foam mattresses

Memory foam (viscoelastic) has often made industry headlines because of its unique properties at the time. It’s also a foam of atypical origins, since it was created by NASA for the special needs of space travel.

The main characteristic (and perhaps the only interesting one) of memory foam is that it is thermally sensitive.

In contact with your body's heat, memory foam molds to the shape of your body under the pressure it exerts. The result is comfort and support that is fully adapted to the characteristics of the sleeper.

However, mattresses using this type of foam are not right for everyone:

  • If not infused with thermoregulating gel, memory foam tends to store heat.

  • In case of intense cold, your memory foam mattress will be harder when you get into bed, since the heat transmission between your body and the foam will be slower…

  • Memory foam mattresses are also among the most expensive, because of the technology, but also because of the density (the memory foam used in mattresses is generally high density). However, this allows them to be very durable.

So, if you quickly feel too warm in bed, especially in the summer, memory foam mattresses without gel are to be avoided, otherwise you will sleep poorly.

The comfort provided by memory foam mattresses is not uniform throughout the year. In winter, you will feel like you’re laying on a piece of marble for several long minutes!

Finally, if you're looking for an affordable mattress, just move on!

Classic hybrid foam mattresses

Classic hybrid foam mattresses are made up of three layers:

  • A first latex layer

  • A second memory foam layer

  • A third layer made of high resilience foam

This type of foam is called "hybrid" because it combines different types of foams and latex. The mattresses offered by Polysleep are different (see next paragraph).

Hybrid foam mattresses have the advantage of purely and simply canceling the biggest defects of memory foam:

  • Hybrid foam does not need heat to mold itself to the body of the sleeper.

  • Usually has an open-cell structure, which allows for optimal ventilation of the mattress.

  • Hybrid foam is reactive. The rebound (i.e. the return to the initial shape after applying pressure on the foam), is much faster than with memory foam.

Finally, hybrid foam will appeal to those who can't stand the "mold" that memory foam creates around their body once it has finished reacting to the heat and pressure it exerts.

It will also appeal to those who have difficulty changing sides because of that same mold.

But what about Polysleep's hybrid foam mattresses?

Polysleep's New Generation Hybrid Foam

Partially folded Polysleep hybrid foam 

As we were saying, our hybrid foam mattresses are different from the others!

First of all, our mattresses do not contain latex. For us, your allergies shouldn't prevent you from getting the best sleep possible.

What about the different layers?

Polysleep Mattresses


Polysleep certified antimicrobial mattress bed installed in front of a wardrobe


They are made of 4 layers of foam:

A 1st layer of Polysleep hybrid viscoelastic foam, ventilated and antimicrobial, with a density of 3.0 lb/ft³ and ISO 20743 certified.

The 2 following layers are made of polyurethane foam:

  • 2nd layer: Transitional polyurethane foam, with a density of 1.8 lb/ft³.

  • 3rd layer: Supportive polyurethane foam, with a density of 1.8 lb/ft³.

Finally, the originality of our mattresses is that they have a final layer: a support frame made of high-resistance polyurethane foam with a density of 2.0 lb/ft³.

So, contrary to some other brands on the market, the edges of Polysleep mattresses do not sag…

Zephyr Mattresses


The Polysleep Box with the Zephyr mattress

They are made of 5 layers, and 6 different types of foam:

A 1st layer of Polysleep hybrid foam infused with GelFlex Plus, with a density of 2.6 lb/ft³.

A 2nd layer of viscoelastic, ventilated and antimicrobial Polysleep hybrid foam, ISO 20743 certified, with a density of 3.0 lb/ft3.

Two layers of polyurethane foam

  • 3rd layer: Transitional polyurethane foam, with a density of 1.8 lb/ft³.

  • 3rd layer (center): Targeted polyurethane support foam in the center of the mattress, with a density of 2.0 lb/ft³.

  • 4th layer: Supportive polyurethane foam, with a density of 1.8 lb/ft³.

Finally, the Zephyr mattress is also equipped with a support frame made of high-resistance polyurethane foam with a density of 2.0 lb/ft3.

In summary...

The combination of polyurethane foams and viscoelastic hybrid foams specially developed by Polysleep, and certified by the CertiPUR-US program, makes our mattresses outstanding products!

They’re designed to last over time and offer you unparalleled comfort, night after night.

Quite simply, it is the best value for money available on the Canadian market!

What is the best foam mattress density for you?

Well, it depends on many things!

Okay fine, that doesn't help you much...

In fact, this will depend on two main variables:

  • Your Body Mass Index (the famous BMI),

  • Your sleeping position.

Importance of the BMI

As mentioned above, the density of the foam in your mattress is chosen according to your body shape! And when one says morphology, the BMI is necessarily implied.

  • For a BMI lower than 20:

Low-density foam mattresses may be suitable because they will be subjected to less stress related to your weight.

However, medium to high density foam mattresses can provide the same level of comfort, while being more durable and adapted if you change your lifestyle.

  • For a BMI between 20 and 30:

Forget low density foam mattresses, and get one made of medium to high density foam.

  • For a BMI higher than 30:

High density foam mattresses will be the best choice for optimal and long-lasting support.

Importance of the sleeping position:

Another point to consider when choosing the density of the foam in your mattress: your sleeping position!

If you sleep on your side, choose a medium to high density foam. It can be hybrid or memory foam, for maximum relief of the various pressure points located at the hips and shoulders.

On the other hand, for back sleepers, there are more choices!

However, it’s better to choose medium to high density foam mattresses: they will offer better support for your spine.

Conversely, if you sleep on your stomach, low-density foam mattresses are to be avoided at all costs. The lack of support will cause your back to arch too much. So, turn to medium density or even high density foam mattresses.

Conclusion: Hybrid foam mattresses, the best compromise

After all, there is no shortage of foam mattresses! Many choices are available...

Here below is our ranking of the best types of foam mattresses based on price, comfort, support, and durability over time.


  1. New generation hybrid foam mattresses:

  • Outstanding support, personalized and durable, thanks to the combination of viscoelastic hybrid foam and polyurethane foam.

  • Homogeneous comfort all year round.

  • Maximum ventilation for nights at the right temperature.

  • One of the best life services on the market.

  • Reasonable price for the benefits provided.

In our opinion, this is the best compromise currently available for foam mattresses, and that is why we use this type of foam in our mattresses.

  1. Classic polyurethane foam mattresses:


  • Long-lasting support and comfort, but without being equal to those of hybrid foam mattresses.

  • Very long lifespan.

  • Like hybrid foam mattresses, they offer optimal ventilation.

  1. Memory foam mattresses:

Given the previous two types of mattresses, memory foam models, which tend to retain heat, cannot compete... Not to mention they don’t provide year-round comfort.

  1. Polyether foam mattresses:

As for polyether foam mattresses, they are far behind in terms of support and durability…

Foam Mattress Type



Foam Density




Best value for money


Mid to high density

Very good support

Best option on the market

Classic polyurethane only

Second best value for money

Quite durable

Mid to high density

Good support

Offers less benefits for a similar price


Most expensive option

Very durable

High density

Very good support (except when cold)

Poor ventilation = more heat and more bacteria


Most affordable option

Very durable

Low density

Poor support

For small budgets only

A few more tips:

In terms of density, favour a mattress with medium to high density foams.

To be sure, with such foams, these mattresses can accommodate a wide range of sleepers in terms of BMI and sleeping position.

For all that, be sure to try them out to determine if one model suits you better than another. That's it!

Are you interested in our hybrid foam mattresses? Discover our line of products now. You’ll get a trial period of 100 nights!


Learn more: Also check out our Polysleep mattress for baby!

Baby happy with his new Polysleep baby mattress

If you liked our blog article, please don't forget to Share it with your friends by clicking the button below!


For a Better Price

Your Cart

Your Cart is Empty
Please select your country

It seems like you're not in the right place!
Let us guide you on your path to a better night's sleep.