BBB GUIDE: Everything you need to know about Memory Foam
Memory foam (also known as viscoelastic foam) bridges the gap between polyfoam and latex. While technically a polyurethane-based material, memory foam is treated with additional chemicals for an exceptionally soft and malleable surface. Sleepers who use memory foam report a conforming fit and targeted pressure relief reminiscent of natural latex. Memory foam is widely used for mattress toppers and pillows, as well.
Memory foam is designed to conform around your figure for a customized fit.
Memory foam is engineered to respond to temperature. When you are lying on memory foam, your body heat essentially melts the foam, creating a contoured impression in the mattress than can help spinal alignment and relieve pressure points. Then, once you get up, the mattress will cool and become firmer as the memory foam retains its original shape. Mattresses known as memory foam hybrids are designed with both an innerspring and memory foam layers measuring at least two inches in height. Hybrid options are suitable for sleepers who enjoy memory foam’s conforming qualities but also prefer to sleep on an innerspring.
Many varieties of memory foam are available on the market. Most mattresses feature open-cell memory foam, which is designed for breathability and quick shape retention. However, some mattresses are made with closed-cell memory foam, which is firmer and less breathable. Memory foam may be marketed as ‘100% organic’ or ‘natural’ by some manufacturers and retailers, but the accuracy of these labels has been widely debunked.
Like polyfoam, memory foam is categorized into three grades. The table below features a detailed breakdown of these three categories.
|Grade||Density (Pounds per Cubic Foot)||Qualities|
|Low||2.5 to 3.9 lbs/ft3||Good motion isolation, some contouring and retains original shape rather quickly|
|Medium||4.0 to 5.4 lbs/ft3||Very good motion isolation, adequate contouring and retains original shape rather slowly|
|High||5.5 lbs/ft3 and higher||Excellent motion isolation, excellent contouring and retains shape very slowly|
Identifying your most important criteria is key to selecting a memory foam mattress, as each grade carries noticeable perks and drawbacks. Low-density memory foam is the least expensive option, and this material will also retain its original shape in the least time. However, this grade is also characterized by middling motion isolation, poor contouring and a relatively short lifespan. Alternatively, high-density memory foam will carry a hefty price tag and is slow to retain shape, but this grade is considered the best memory foam option in terms of motion isolation, conforming and longevity. Medium-density memory foam, as the name implies, is a middle-of-the-road option that ranks between the two other density grades for virtually all criteria.
Due to its complex composition and similarities to latex, memory foam is also measured for ILD. In most memory foam mattresses sold today, the ILD ranges between 10 and 20; an ILD of 13 to 15 is considered optimal for the average sleeper. You may find some memory foam models with an ILD lower than 10, but beware: these mattresses will be too soft and prone to sinking for most people, particularly heavy-set individuals. Likewise, any memory foam mattress with an ILD of more than 20 will probably be too firm.
Reviews for memory foam mattresses are somewhat mixed. Although most users rate memory foam higher than polyfoam in terms of comfort and overall support, the material still carries a few drawbacks. One major issue is odor. Like polyfoam, memory foam can produce high levels of off-gassing. This quality is common to all three memory foam grades, although the most persistent off-gassing smells have been reported in high-density memory foam.
Memory foam is also considered significantly less durable than latex. A common complaint among long-term users is that their memory foam mattress will sag in certain places over time (depending on their sleeping position). This can cause sleeper discomfort, and in some cases may exacerbate chronic back or joint pain. Regardless of density, most memory foam mattresses have a lifespan of six to eight years; the lower the memory foam’s density, the shorter the lifespan. Premature sinking is less common in mattresses that contain thin layers of memory foam.
Finally, memory foam has been criticized for poor heat retention. Even low-density memory foam is thick enough to trap your body heat while you sleep, but ‘sleeping hot’ complaints are most commonly associated with medium- and high-density memory foam mattresses. In recent years, memory foam infused with gel beads ― known simply as gel foam ― has become a popular alternative to traditional memory foam because it sleeps cooler. Gel foam may be a suitable option if you tend to become too hot when you sleep.
Memory foam mattresses vary considerably in terms of price. A standard memory foam model will cost anywhere from a few hundred dollars to several thousand, although most buyers pay less than $1,500 for a new mattress. Memory foam hybrids tend to be a bit costlier; you should expect to pay at least $2,000, although luxury brand models may cost more than twice that much.
If you are considering a memory foam mattress, here are a few questions to ask.
- What is the density? The density of a memory foam mattress will affect contouring, motion isolation, heat retention, shape recovery, off-gassing levels and price. First determine which density most closely aligns with your needs and preferences, and then you can decide which brands and models will work best. Also keep in mind that memory foam mattresses with low density will have a shorter lifespan than high-density mattresses.
- What is the ILD? Although an ILD of 13 to 15 is considered optimal, every sleeper has different preferences when its comes to softness and firmness.
- How thick are the memory foam layers? Mattresses with thin memory foam layers are more resilient and less prone to sagging, while thick layers are associated with poor shape recovery and a short lifespan.