What is a latex mattress?

WHAT IS LATEX?

Latex is a highly elastic type of foam rubber often used in mattresses because it offers high levels of comfort. The composition of latex can vary from 100% synthetic latex to 100% natural latex. As the percentage of natural latex increases, so does the elasticity, breathability, durability, and comfort.

WHAT IS THE DIFFERENCE BETWEEN NATURAL LATEX AND SYNTHETIC LATEX?

Natural latex comes from the sap of the rubber tree (Hevea brasiliensis). This sap is poured into a mold and then fired according to specific procedures, depending on the desired type of latex.
A mattress can be considered a natural latex mattress if it consists of 85% natural latex. It's also now possible to make mattresses that consist almost entirely of natural latex. So be sure to inquire about the exact percentage of natural latex in your mattress. To ensure you're sleeping on a natural latex core whose latex comes from responsibly managed forests, make sure your mattress carries the FSC® label.
Synthetic latex, on the other hand, is made from petrochemicals and is a human imitation of natural latex. The advantage of this latex is that it's cheaper, but the disadvantage is that these mattresses offer less ventilation and are less elastic and durable.

ARE LATEX MATTRESSES GOOD MATTRESSES?

The answer to the question of whether latex mattresses are good mattresses is "Yes," but that same 'good' latex mattress can also be a bad mattress if it is not placed on the appropriate mattress base.
Latex mattresses are ideal for use with adjustable slatted bases. The elastic latex ensures the slatted base can function properly. Because the latex is baked in a mold whose structure has been carefully studied, the latex core is easily divided into firmer and softer zones. This ensures good pressure distribution and high levels of comfort while sleeping. Furthermore, surface profiling can be easily incorporated to make the mattress extra soft in specific areas. No other material offers as much resilience and comfort as latex.

Since natural latex is naturally antibacterial and antifungal, dust mites cannot survive in a latex mattress, making them ideal mattress cores for people with dust mite allergies. Another major advantage of latex mattresses is that the elasticity and firmness of the mattress are independent of temperature or pressure. This ensures the mattress provides consistent, appropriate support throughout the night. Furthermore, natural latex is tapped from a rubber tree, a renewable resource that is generally more sustainable than foams made entirely in a factory.

This means that latex mattresses containing at least some natural latex can be considered sustainable. Latex mattresses can be completely CO2-neutral or even CO2-negative (more CO2 is removed from the air by the tree than is emitted during the mattress's production process). The manufacturers of the latex brand Heveafoam® therefore call it a "mother nature's reward product."
Another major advantage of natural latex mattresses is their excellent microclimate thanks to their open cell structure and perforations. This promotes the mattress's ventilation and moisture-regulating properties.
Finally, latex mattresses are dimensionally stable, meaning you can enjoy the same good comfort of the sleeping system all night long.

Want to know if your base and mattress combination provides the right support? Try the "broomstick" test: Lie on your side on the mattress and hold a broomstick horizontally at the height of your spine. If your spine is level with the broomstick, you can assume you have an ergonomic sleep system.

WHAT ARE THE ADVANTAGES AND DISADVANTAGES OF A LATEX MATTRESS?

The table below lists the pros and cons of latex mattresses. Keep in mind that this generally applies to both natural and synthetic latex, but with synthetic materials, these advantages are slightly less pronounced.

DOES A LATEX MATTRESS FITS ON EVERY TYPE OF BASE?

No, with latex mattresses, it's very important that the base is sufficiently adjustable and is best combined with a slatted base. Latex itself offers less support, so the base needs to make a difference, especially around the shoulders, waist, and pelvis. We prefer slatted bases where the firmness of each slat can be adjusted based on your body type. The latex mattress serves as a comfort layer between your body and the slatted base and provides some extra space where needed. If you'd like more information about what makes a good slatted base, don't hesitate to read the following article.

IS LATEX SUSTAINABLE?

The sustainability of latex depends heavily on the type of latex and the production method. However, there are several arguments for considering (natural) latex a sustainable product:
Natural latex comes from a renewable source, namely rubber trees. Another major advantage of natural latex is that it is biodegradable and compostable. In contrast, synthetic latex is derived from crude oil, a finite resource that is becoming increasingly scarce. Therefore, natural latex is generally more sustainable than synthetic latex. Fortunately, there is currently a strong focus on mattress recycling.

Besides the product's origins, the bigger picture must be considered, including its environmental and social impact. What was the land used for before the rubber plantations were planned? How high is the workload on the plantations, and do the workers receive a fair wage? How quickly do the workers begin replanting new rubber trees? What happens to the old trees? How is the transport from the plantations to the factories handled? These are all questions that should be considered, and the answers to which can vary significantly between mattress manufacturers. Sit and Sleep prioritizes sustainability and environmental friendliness. That's why we sought out manufacturers who thoroughly research the origins of their latex, and we've established a successful partnership with Recor, Revor, and Riviera Beds.

Manufacturers' R&D (Research and Development) departments are constantly looking for ways to minimize their environmental impact. To give manufacturers an idea of ​​whether they are doing well in terms of environmental friendliness and sustainability, a Life Cycle Assessment (LCA) can be performed to map the environmental impact of products and human activities. This involves examining the entire process, from raw material extraction to waste disposal.

FROM MILK JUICE TO MATTRESS, WHAT ARE THE DIFFERENT PROCESSES?

A latex mattress is, in short, "baked rubber with a protective cover." The most commonly used baking method is the Dunlop Method, a method in which the latex is baked to a specific density in a mold, making it easy to create comfort zones. To make the latex extra flexible, it can first be placed in a vacuum, then frozen, and then baked. This latex is then called Talalay Latex.

DUNLOP METHOD: Every latex mattress begins with a type of latex. Depending on the composition, this latex consists of 100% natural latex, a blend of natural and synthetic latex, or 100% synthetic latex. This latex is mixed with, among other things, a type of salt, and then the liquid is foamed with air. When air is mixed into the latex, the open-cell structure of the latex is created, which provides the ventilation, heat, and moisture-regulating properties of latex mattresses. The amount of air added determines the firmness of the mattress. The liquid foam is poured into a steel mold, resembling a very large "waffle iron." The thickness and position of the bars in the mold determine the number and firmness of the mattress's zones.

The mold is carefully sealed so the latex can be baked. Baking the latex is also called the vulcanization process. After vulcanization, the latex core is removed from the mold and washed several times to remove any residue. The water is then squeezed out and dried. Finally, the core's quality is carefully tested. The core then needs a cover, and then the mattress is ready to be shipped to the distributor.

TALALAY METHOD: Talalay latex, sometimes confused with Radium Foam (a manufacturer of Talalay latex), is made from the same latex of the rubber tree as in the Dunlop method. The latex is mixed and then poured into a mold. Unlike the Dunlop method, the mold is only filled 30 to 60% of the way full. The firmness of the mattress is determined by the percentage of latex to air. The mold is then closed and vacuumed. This ensures that the latex is evenly distributed throughout the mold. The latex is then cooled using nitrogen to approximately -30°C. During the freezing process, the bubbles burst, creating an open-cell structure. After freezing, a Talalay latex mattress undergoes the same steps as mattresses baked using the Dunlop method: heating to vulcanize the latex, washing, squeezing out the water, drying, and testing.

WHAT EXACTLY IS THE DIFFERENCE BETWEEN TALALAY LATEX AND DUNLOP LATEX?

As described above, the Talalay method involves two additional steps: vacuuming the mold and freezing. There are also some other differences: In the Dunlop method, the open-cell structure is created by mixing the latex with air, while in the Talalay method, this is achieved by only partially filling the mold with the latex and then vacuuming it. Another difference lies in the chemicals added to the latex to solidify the liquid: in the Dunlop method, gelation occurs through the addition of sulfur, while in Talalay latex, this occurs through carbon dioxide. The different methods also give different properties to the latex mattresses. Below, we briefly summarize the advantages of each method.

Advantages of the Dunlop method:

• Natural latex does not tolerate very low temperatures well, which is why mattresses baked using the Dunlop method generally last longer than Talalay latex mattresses.
  
• The Dunlop process is cheaper, which means the sales price of these mattresses is also lower without compromising the quality of the latex.
• The higher density of the latex allows for greater variations in firmness within the comfort zones. This makes this latex very suitable for the latex core of a mattress.
• Because the milky sap does not need to be frozen in this method, this process is less harmful to the environment.

Advantages of the Talalay method:

• Talalay latex can be made even more elastic and softer than latex baked using the Dunlop method. This makes Talalay latex an excellent covering for mattresses, such as pocket spring mattresses.
• In Talalay latex, the open cell structure is generally larger than in Dunlop latex, which benefits the ventilation properties of the latex.

WHAT'S BETTER? LATEX MATTRESSES OR ANOTHER FOAM?

There are four different types of foam used to make mattresses: polyether (PE foam), cold foam (HR), memory foam, and latex. There's no such thing as "the best mattress" because various factors must always be considered: ergonomics, sleep comfort, durability, budget, and usage. When considering ergonomics, one material stands out for us: latex. Below, we briefly explain the different materials and their advantages and disadvantages.

POLYETHER FOAM MATTRESSES (PE MATTRESSES)

PE mattresses are 100% synthetic mattresses made from petroleum. They're not sold very often anymore due to their closed-cell structure, which means they offer little ventilation and are prone to dents. They're very firm and offer little support or comfort. The advantage of these mattresses is their affordability.
Polyether foam is sometimes also called PU or PUR (polyurethane) foam. PU foam is the umbrella term for all foams derived from petroleum. This includes PE mattresses, as well as cold foam and memory foam mattresses, which will be discussed further.

COLD FOAM MATTRESSES (HR MATTRESSES)

Cold foam, also called High Resilience foam (HR foam), is a 3D polyurethane foam with a higher resilience than polyether. Cold foam mattresses owe their name to the production process in which the mixture of polyurethane, polyol, and MDI chemicals is placed in a cold mold. The amount of polyol largely determines the quality of the mattress.
Cold foam is one of the most commonly used materials in the mattress world. Thanks to their open-cell structure, these mattresses offer excellent ventilation and moisture management. Compared to cheaper mattresses, they are more flexible and elastic, resulting in better pressure distribution. The mattress offers more support, feels more comfortable, is less likely to dip, and lasts longer. However, most cold foam mattresses lack the elasticity to provide sufficient spinal support. Because of their synthetic origins, these mattresses are also less environmentally friendly than mattresses of natural origin, such as latex.

MEMORY FOAM MATTRESSES

Memory foam mattresses are available under many different names: Tempur, NASA foam, memory foam, viscoelastic foam, slow-motion foam, lazy foam, and more. It's a foam developed by NASA with excellent pressure-distributing properties. It's a temperature-sensitive material that softens as it warms. This allows the mattress to conform to the body's contours and optimally distribute pressure. This is why memory foam mattresses are effective in preventing pressure sores in bedridden individuals.
The fact that the firmness of memory foam depends on the temperature also has some drawbacks. When people don't heat their rooms in winter, the mattress is initially very firm. The mattress softens with body temperature, but this is only true where the person lies. As a result, people are much less likely to move around in their sleep, which is crucial for nutrients to reach the intervertebral discs. A constant room temperature is therefore recommended if you do choose this type of mattress. Furthermore, memory foam doesn't ventilate well, causing people to sweat much faster. Finally, memory foam mattresses often develop a hammock effect because many people's pelvis is heavier than their shoulders. Therefore, these mattresses must be combined with a well-supporting base.

LATEX MATTRESSES

For us, there's one mattress material that stands out above all other foams: latex. Although latex mattresses are often considered a type of foam, latex isn't actually foam, but a dimensionally stable foam rubber that's much more elastic than other foam types. Thanks to its high elasticity, latex mattresses can be very soft and comfortable, depending on the quality of the latex. This is one of the main reasons why latex is often preferred. Its flexibility ensures optimal support from an adjustable slatted base and even pressure distribution. Another advantage of latex is that the material can be 100% naturally sourced, making it a generally more sustainable material. You can also adjust the density and size of the perforations in the latex core. This creates a wide variety of firmness levels and makes it easy to divide the mattress into different ergonomic comfort zones. The open-cell structure ensures good ventilation, heat distribution, and moisture regulation. Finally, latex is naturally anti-fungal, anti-bacterial, and anti-dust mite, which is beneficial for people who suffer from allergies.

WHAT DOES LATEX DO IN A MATTRESS?

There are full mattress cores made of latex, but latex is also often used as the top layer of a pocket spring mattress, for example. This is because latex is highly elastic, allowing it to provide the necessary support from the underlay while simultaneously offering a high level of comfort. This underlay can be an adjustable slatted base in the case of a full latex mattress, or the spring core of a pocket spring mattress. Furthermore, the antibacterial, anti-dust mite, and anti-fungal properties of latex make the mattress suitable for people prone to allergies to certain substances.

WHAT ABOUT LATEX ALLERGIES?

For people with a latex allergy, it's important to know what type of allergy it is: a contact allergy (type IV) or a fragrance allergy (type I). The most common form is a contact allergy to latex. With this type, latex mattresses usually pose no problem, as there are several layers between the mattress and the skin. In the case of a type I latex allergy, the immune system reacts to the proteins in the natural rubber, and it's best to choose a different type of mattress. Be sure to consult an ergonomic consultant.

WHAT IS THE BEST LATEX MATTRESS?

There are so many different latex mattresses available, making it difficult to see the forest for the trees. The fact that there's no such thing as "the best mattress," as this depends heavily on the user's body type and the quality, adjustability, and flexibility of the mattress support, makes choosing the right latex mattress even more challenging.
Fortunately, there are several guidelines you can consider when choosing a mattress. We'll briefly outline them. Keep in mind that these are theoretical guidelines. It's important to have your spine's position checked by a professional before purchasing a mattress.

HOW THICK SHOULD THE MATTRESS BE?

A latex mattress should be at least 16 cm thick to provide sufficient comfort while sleeping and no thicker than 21 cm to ensure the slatted base has sufficient influence on the sleeping position. Thicker latex mattresses generally offer more comfort than thinner ones.

WHAT IS THE BEST FIRMNESS FOR A LATEX MATTRESS?

The firmness depends primarily on the body weight and height of the person sleeping on the mattress. The ideal firmness also depends on the thickness of the mattress. Thicker mattresses can be slightly softer than thinner ones. The table below provides a guideline for mattress firmness based on body weight and height:

HOW MANY ZONES SHOULD THE MATTRESS HAVE?

The number of zones depends on the person's body type. Generally speaking, we distinguish five body types: pear, hourglass, apple, triangle, and rectangle.
The mattress must therefore be adapted to the body type of the sleeper. People whose pelvis is wider than their waist usually sleep best on an X-mattress with 7 zones (head - shoulders - waist - pelvis - waist - shoulders - head). It is important that the waist is firmer than the pelvis. People with wider shoulders in relation to the waist and pelvis usually sleep best on a Y-mattress with a firmer pelvic zone. There are two types of these mattresses: 3-zone mattresses (head and shoulders - waist and pelvis - head and shoulders) and 5-zone mattresses (head - shoulders - waist and pelvis - shoulders - head).

Whether or not the mattress has a headrest has little effect on spinal alignment. These mattresses are sometimes also called V-shaped mattresses.
As you may have noticed, most mattresses are constructed symmetrically so that the mattresses can be slept on on four sides and can therefore be turned.
Note: Everyone is unique, and weight distribution can vary from person to person. For example, people with a wide, relatively heavy pelvis may prefer a mattress with 3 or 5 zones rather than one with 7 zones. Therefore, consult an ergonomic consultant when choosing a mattress.

WHICH COVER SHOULD THE MATTRESS BE FINISHED WITH?

The general rule is: the more natural, the better. Natural materials like wool and cotton regulate moisture and heat better than synthetic materials. By incorporating wild silk into the cover, it will wick away heat and moisture even more effectively.
How the raw materials are woven into the mattress cover, also called ticking, is also important. A classic woven cotton mattress cover hardly stretches and creates a stiffer sleeping comfort, even if softer layers are incorporated into the mattress. A ticking that stretches, for example, by incorporating polyester fibers, will conform to the body's contours much better. The effect on sleeping comfort is surprisingly significant. The raw materials can also be knitted together, making the ticking extra stretchy. This, however, will make the mattress cover somewhat less ventilated and moisture-wicking.
The natural materials in mattress covers are usually not machine washable. If you suffer from allergies, consider a washable cover made of synthetic materials, such as thermal wadding or dacron fibers. Note: these covers are less ventilated, making you sweat more easily.

HOW LONG DO LATEX MATTRESSES LAST?

The average lifespan of latex mattresses is between 8 and 12 years. This depends on how often the mattress is used, whether the user perspires heavily during the night, how well the mattress is maintained (rotated every three months, aired thoroughly during the day, changed linens regularly, etc.), and the thickness and firmness of the mattress.
To see if a mattress is worn out, it's best to look at the core. The elasticity of the mattress decreases with age. It becomes firmer and darker in color; it's best to replace the mattress before the latex begins to crumble. You can usually also feel that the mattress is worn out because the support is no longer sufficient, especially in the areas where the mattress is most stressed, namely the pelvis or shoulders. The mattress will also sink in a bit more in those areas.