Memory foam mattresses

Six to seven years for a typical foam mattress, according to the Sleep Foundation, and longer for high-density foam. What actually wears out is the top 3 or 4 inches, where your body compresses the foam every night, while the support base underneath lasts far longer. That is why a memory foam mattress with a replaceable comfort layer, like the Viscosoft Edge, can keep going after the surface has softened: you swap the layer and the rest of the mattress stays in service.

Traditional memory foam does, because it molds closely around your body and traps the heat you give off. How much depends on the mattress. A solid foam core holds heat, while a hybrid base with pocketed coils lets air move under the comfort layer, and a knit cover that wicks moisture helps on top of that. The Edge Signature hybrid is the cooler of the two Viscosoft builds for that reason. On a foam mattress you already own, a breathable protector and cotton sheets help.

It can be, as long as the firmness is right. Memory foam relieves pressure at the hips and shoulders better than most materials, and a randomized trial of 313 people with chronic low back pain, published in The Lancet, found medium-firm mattresses reduced pain more than firm ones. The risk with memory foam is going too soft, so your hips sink and your spine curves. Our guide to mattresses and back pain covers how to tell which problem you have.

Look for a comfort layer of at least 4 pounds per cubic foot. Density is the weight of a cubic foot of the foam, and it predicts how long the foam keeps its shape: foam under 3 pounds per cubic foot is low density and softens fastest, 3 to 5 is medium, and 5 and above is high density and the most durable. Brands rarely print this number, so ask. Denser foam also feels slower and more contouring, and it costs more, which is where cheap memory foam mattresses cut corners.

Memory foam is slow to recover its shape and molds to you, while high-resilience foam springs back immediately and feels bouncy. A high-resilience foam mattress uses that springy foam for support or transition layers, where quick recovery keeps the surface stable, and often a thin layer of memory foam on top for contouring. Memory foam on its own gives the deepest pressure relief but can feel like it holds you in place, so most well-made foam mattresses combine the two.

New foam releases a chemical smell for a few days as leftover manufacturing compounds escape, a process called off-gassing. It is strongest on a mattress that arrives compressed and sealed. CertiPUR-US certification, which the Edge Signature foams carry, means the foam was tested for low emissions and made without certain flame retardants, heavy metals and ozone depleters. Hence, the smell is milder and shorter-lived. Leave the mattress uncovered in a ventilated room for a day or two and it clears

No. Nearly every memory foam mattress is built in layers with the comfort foam on top and firm support foam underneath, so flipping it puts you on the hard base. Rotating it head to foot every few months spreads the wear and is worth doing. On a modular mattress the question goes away, because the comfort layer comes out: when it softens or you want a different feel, a replacement comfort layer goes in and the base stays as it was.

Vacuum it, spot clean stains with a barely damp cloth, deodorize with baking soda and let it dry completely. Never soak memory foam, steam clean it or use bleach, since the foam holds moisture and can grow mold inside. A mattress with a removable cover is far easier: on the Edge and Edge Signature, the cover unzips and goes in the washing machine, following the instructions on our care page. Our full guide on how to clean a mattress covers every stain.

The things reviewers consistently score are pressure relief, how hot it sleeps, edge support, motion isolation and how it feels after a year, not just on night one. A top rated memory foam mattress on a review site is a snapshot of those scores, so read the durability and heat sections, not just the star rating. Then check what ratings cannot tell you: the foam density, the comfort layer thickness, the trial length and whether you can change the feel after you have slept on it.