Let's get one thing out of the way: no mattress cools you down. What a mattress can do is trap less of the heat you give off, so you don't wake at 3 am lying in a warm hollow. Some materials are much better at that than others, and your bedding matters more than any of them. Here's what we tell hot sleepers in store.
Quick answer
- Change the duvet and sheets first. A wool or feather duvet that's too heavy for the season, or polyester sheets, make more difference than the mattress.
- Then choose a mattress that breathes: a spring unit (air moves through it), latex or open-cell foam in the comfort layer, and wool or cotton rather than thick synthetic padding on top.
- Avoid deep, dense foam tops that you sink into. The further you sink, the less air gets round you.
- Our picks: the Opulence (Viscoool open-cell foam), the Latex Luxury range, and the Comfort Touch EcoGel.
Why you get hot in bed
You give off heat all night and your body wants to drop its core temperature to sleep well. Anything that holds warm air against you works against that: a duvet that's too heavy, sheets that don't breathe, or a mattress surface that wraps round you and traps the heat. New Zealand houses add their own twist. In winter the bedroom is 12 degrees and you pile on the layers; by November the same layers are still on the bed and the upstairs room is 24 degrees at midnight.
Start with the bedding
Before you spend thousands on a mattress, spend a hundred on the bed. A lighter-weight duvet for summer, or a wool duvet in a lower warmth rating, and cotton or linen sheets rather than polyester blends. Wool is unusual in that it's warm in winter and wicks moisture in summer, which is why we use wool blends in so many of our pillow tops. Our bedding range covers duvets and sheets, and the Tencel waterproof protector is breathable, which most waterproof protectors aren't.
What makes a mattress run hot or cool
- The spring unit breathes; solid foam doesn't. An innerspring or pocket spring mattress is mostly air. Every time you move, air moves through it. A solid foam mattress has nowhere for warm air to go, which is why "mattress in a box" owners so often complain of heat.
- Latex breathes better than foam. Natural latex has an open structure and is usually pin-cored with ventilation holes. It also springs back rather than letting you sink, so there's more air round you.
- Open-cell foams like the Viscoool in our Opulence are designed to let air and moisture through rather than hold them.
- Gel in a comfort layer, as in the Comfort Touch EcoGel, is there to move heat away from the surface and spread it.
- Natural fibre tops (wool, cotton, bamboo) wick moisture; thick synthetic quilting holds it.
- Depth of sink. A plush top you sink into feels lovely in the showroom and warm at 3 am. If you run hot, a firmer top with a thinner comfort layer runs cooler, whatever it's made of.
The beds we'd point a hot sleeper to
- Opulence: firm, pocket spring, with Viscoool open-cell foam that the product page describes as promoting airflow and preventing moisture build-up and hot, sweaty sleep. Natural wool pillow top, organic cotton ticking. 310 mm, from $1,199 (Single, mattress only). Our first recommendation for a hot sleeper who likes a firm bed.
- Latex Luxury Medium (and Firm): a solid core of certified organic latex, no springs, no synthetic foam, covered in organic cotton. Latex has superior air circulation and doesn't hold moisture. 210 mm, from $1,649, 10 year warranty. The cleanest answer if you also have allergies.
- Windsor Latex: medium-soft, with a thick latex and wool pillow top over an Innergy coil. For hot sleepers who want a softer feel. 335 mm, from $1,649.
- Comfort Touch EcoGel: medium, with an Eco Gel and latex pillow top in wool and silk fibres and a coil-in-coil Therawrap unit; the product page lists enhanced airflow and heat dissipation. 340 mm, from $3,599. Our top-of-range answer.
- Supreme Luxury: soft, with a latex and wool top and natural bamboo-fibre fabric for moisture absorption. 320 mm, from $2,499. The soft bed for people who normally find soft beds hot.
All of these are in the Therawrap and soft ranges depending on feel. If you share a bed, a pocket spring also means your partner's heat and movement stay on their side.
What not to buy
A mattress with a deep synthetic foam top that you sink into, however it's marketed. And don't choose a bed on temperature alone. A mattress that runs cool but doesn't support your back has swapped one bad night for another. Pick your firmness for how you sleep, then narrow it down to the breathable options at that firmness.
Frequently asked questions
What's the best mattress for hot sleepers?
A spring or latex mattress with a wool, cotton or latex top rather than deep synthetic foam. The Opulence and Latex Luxury are our usual suggestions.
Is a cooling mattress worth it in NZ?
A breathable one is. Nothing "cools" you, but a mattress that doesn't trap heat makes a clear difference from November to March.
Is latex good for hot sleepers?
Yes. It breathes, it doesn't hold moisture, and you lie on it rather than in it.
How can I make my current mattress cooler?
Lighter duvet, cotton or linen sheets, a breathable protector, and a window open. Then look at the mattress.
Do soft mattresses sleep hotter?
Usually, because you sink further in. A soft bed with a latex or wool top, like the Supreme Luxury, is the exception.
Come in when it's warm
The best time to test a mattress for heat is a warm afternoon. Lie on a couple for ten minutes each and notice which one you've warmed up. Any store, or the Bed Selector to shortlist first.
Related guides: Best mattress firmness for every sleeping position · Can a mattress topper make your bed more comfortable · Bedding
