Is a Latex Mattress Hot To Sleep On?

In my experience, high-quality natural latex mattresses are actually one of the coolest foam options you can buy, especially when compared to memory foam mattresses.

The confusion comes from a misunderstanding of what makes a mattress hot. The problem isn't usually the type of foam, but the total amount of it. If you're sleeping hot, the thickness of your mattress's comfort layers is almost always the main culprit. Your body heat needs somewhere to go, and a thick slab of any insulating material—whether it's natural latex, synthetic latex, or memory foam—will trap it.

This article will break down the science of mattress heat, compare the different mattress types, and explain why latex mattresses have a (mostly unearned) reputation for heat.

Why do some mattresses sleep hot? The science of heat retention

Your body is a radiator, constantly giving off body heat. For you to get a deep, restorative night's sleep, your body temperature actually needs to drop slightly. If your mattress traps that heat and reflects it back at you, your sleep temperature rises, disrupting your sleep quality and causing you to toss and turn.

The ability of a mattress to trap heat is all about its mass and insulating properties. Think of it like a frying pan: a thin pan heats up fast and cools down fast. A thick, heavy, cast-iron pan takes a long time to heat up, but once it's hot, it stays hot for ages.

Foam works the same way. All foam is an insulator. The more foam you have, the more heat it can absorb and store. This is the central issue with heat retention.

• Memory foam is typically dense and has a closed cell structure that traps air, making it an excellent insulator and the worst offender for sleeping hot.

• Latex mattresses have a very different structure of latex, which I'll explain next.

The key takeaway is this: a 30cm-thick all-foam mattress, even one made of natural latex, will almost always sleep warmer than a spring mattress that has just 5cm of latex foam on top. The volume of foam is the biggest factor in heat retention.

Comparing foam types: latex and memory foam

When people talk about sleeping hot, the comparison almost always comes down to latex and memory foam. As someone who has sold mattresses made with both, I can tell you they are not created equal when it comes to temperature regulation.

Memory foam

Memory foam (or viscoelastic polyurethane foam) is a petroleum-based plastic. It's famous for its slow, sinking feeling. It's designed to soften in reaction to your body temperature and pressure, "moulding" to your shape.

This very property is its downfall for temperature regulation. To soften, it must absorb your body heat. Its dense, closed cell structure (or at least less open) doesn't allow for much air circulation, so that heat has nowhere to go. Many memory foam mattresses are notorious for this, leaving hot sleepers feeling like they're trapped in warm sand.

Natural latex

Natural latex is a completely different beast. It's a natural product derived from the sap of rubber trees. It's processed into a foam that is buoyant, responsive, and springy. You sleep on latex mattresses, not in them.

Crucially, natural latex has two features that make it fantastic for hot sleepers:

1. A natural open cell structure.

2. Large pinholes from the manufacturing process.

This open cell structure is inherent to the latex material. It means the foam itself is riddled with millions of tiny, interconnected bubbles. This open cell structure allows air to move freely, which is fundamental to the breathability of latex mattresses.

This structure of latex is a world away from the dense structure of traditional memory foam, and it's the primary reason latex mattresses provide better temperature regulation.

What makes natural latex mattresses cooler?

When we talk about the cooling benefits of latex mattresses, we are almost always talking about natural latex mattresses, not synthetic latex.

The open cell structure

As I mentioned, the open cell structure is the single biggest factor. This natural breathability means that as you move throughout the night, your body pressure helps pump warm air out and pull cool air in. This constant, passive air circulation is essential for wicking away heat and moisture from the sleeper's body.

The pinhole "holes"

If you ever look at a core of natural latex, you'll see it's full of holes. These aren't just for show. In the Dunlop manufacturing process, the liquid sap of rubber trees is poured into a giant "waffle" mould that has metal rods running through it. These rods bake the latex evenly.

When the slab is removed, it leaves behind pinholes, often up to 10mm wide. My theory, from working with this material for years, is that these holes drastically increase the mattress surface area, giving body heat far more avenues to escape. This design is a key part of the breathability of latex and helps reduce heat buildup, promoting a cooler sleep. This is a feature you simply don't find in memory foam mattresses.

Natural vs. synthetic

The natural cooling properties of latex mattresses are most prominent in natural latex. Synthetic latex, on the other hand, is a petroleum product (like memory foam) designed to mimic the feel of latex. It often has a more closed cell structure and doesn't offer the same level of air circulation or durability.

The difference between natural and synthetic latex mattresses

This is an important distinction for hot sleepers.

• Natural latex mattresses: Made from 95%+ sap of rubber trees. They have the pronounced open cell structure and large pinholes I talked about. This is the premium, most breathable option.

• Synthetic latex mattresses: Made from petrochemicals like Styrene-Butadiene Rubber (SBR). Synthetic latex is cheaper and less durable. It often has smaller pinholes (around 4mm in my experience) and a less effective open cell structure, meaning it can trap more heat.

• Blended (natural and synthetic) latex: This is a common middle-ground, mixing natural and synthetic latex to save costs. The heat properties depend on the ratio.

At my factory, I only use 97% Dunlop natural latex imported from Malaysia. The performance of natural latex in terms of both durability and temperature regulation is just so much better than synthetic latex that the choice is clear.

So, can latex mattresses sleep hot? Yes, they absolutely can, under one condition: if they are all-foam.

If you buy a mattress that is a 30cm block of solid latex foam, it will sleep warm. It doesn't matter how great its open cell structure is; you are still sleeping on a massive block of insulation. The heat retention will be significant.

Hybrid mattresses (spring and foam) are, in my opinion, the best possible solution for temperature regulation. They combine a support core of steel innerspring coils with comfort layers of foam, like natural latex.

This design is how latex mattresses excel.

1. The comfort layer: You get a 5-7cm layer of natural latex on top. This provides all the buoyant, responsive comfort and support and pressure relief that latex mattresses offer.

2. The support core: The coil layer underneath is mostly empty space. It's a giant, open chamber for air. This allows for unmatched air circulation right under the foam layer, pulling body heat away from the sleep surface and expelling it from the mattress.

This hybrid system uses the latex material for what it's good at (comfort) and replaces the heat-trapping foam core with air-filled springs. This is how we build our latex mattresses at Ausbeds. It's the key to achieving a cooler sleep and a comfortable sleeping environment.

How to ensure a cooler sleep on latex mattresses

If you are a hot sleeper but want the benefits of latex mattresses, here's what to focus on to get a cooler sleep environment.

1. Choose a spring/latex mattress

I can't stress this enough. An all-foam latex mattress will be warmer. A hybrid mattress with natural latex on springs will provide superior temperature regulation.

2. Check the mattress cover

The mattress cover can play a surprisingly big role. Many companies wrap their latex mattresses in a thick, quilted polyester cover. Polyester is plastic; it doesn't breathe and it traps heat and moisture.

Look for a thin, breathable mattress cover made from natural fibres. Organic cotton covers or covers with Tencel (made from wood pulp) are excellent. They are breathable and help wick moisture, supporting the temperature regulation capabilities of the natural latex underneath. A good mattress cover works with the latex, not against it.

3. Use breathable bedding

This seems obvious, but don't buy a breathable natural latex mattress and then smother it in polyester sheets and a non-breathable mattress protector. These synthetic materials will trap body heat before it ever even reaches the mattress. Stick to linen, cotton, or bamboo sheets to promote air circulation and get a cooler night's sleep.

5. Lose the mattress topper

If you are sleeping hot, adding mattress toppers is usually a bad idea. A thick latex foam or memory foam topper just adds more insulating volume, increasing heat retention and working against your cooler sleeping surface. The one exception is a wool topper, which can actually help with temperature regulation as wool is a natural insulator that also breathes well.

The verdict

For hot sleepers, latex mattresses are often one of the best choices, if you buy the right kind.

A hybrid mattress that combines a spring core with a 5-7cm layer of natural latex is an ideal setup. The natural breathability and open cell structure of the natural latex provides a cooler sleep surface than memory foam. In contrast, the spring core provides air circulation to disperse body heat and maintain an optimal sleep temperature throughout the night.

The latex mattresses provide a comfort that traditional memory foam just can't match without the significant drawback of heat retention. It's this balance that helps you achieve a restful night and a great night's sleep.