The Ultimate Buyers Guide to Memory Foam Mattresses

The Ultimate Buyers Guide to Memory Foam Mattresses


I can’t tell you the number of people I’ve consulted with who had originally made the huge mistake of buying a mattress that had raving reviews online. 90% of the time, the customer either purchases a terrible quality mattress, or a mattress that is good for some customers, but not for them. The end result: the mattress is thrown in the trash, along with a bunch of money – 100% of the time.

These days, there are more knock-off and mediocre quality memory foam products in the market than ever before. What makes matters worse, companies constantly throw out marketing buzzwords to differentiate their products from competitors, claiming that their memory foam uses some specially advanced technology that doesn’t exist anywhere else (note: this is never true). This can be extremely confusing for first-time and return customers alike.

My guide will steer you clear of all the marketing hoopla, “patented technologies”, and outlandish claims that many of these manufacturers make. I like to keep things short, sweet, and factual. After reading this guide, you will be armed with the right tools to go out and maneuver the minefield of purchasing a memory foam mattress.

So, let’s get right to it.

Memory Foam – The Basics

Memory foam mattresses are made from a specially designed material (a fancy way of saying polyurethane) that molds its shape to your body. The material reacts to body heat and pressure: when you lay on the mattress, the foam will evenly distribute your body weight, and when you get up, the foam will go back to normal. This essentially allows you to sleep comfortably on a surface that molds to the contours of your body whilst reducing pressure points. Simple enough, right?

Types of Memory Foam Mattresses

Depending on who you ask, there are 2 main categories of memory foam mattresses:

1. Visco-Elastic.
This is your run-of-the-mill, standard memory foam material. High quality visco material is comfortable to lay on without letting you sink. The material molds to the shape of your body and prevents you from feeling reverberations from other parts of the bed. such as when your wonderful SO gets up to pee for the 5th time that night.

The main issue that people can experience with visco material is heat retention. Some visco memory foam mattresses (typically those of cheaper, lower quality) are not breathable enough, trapping your body heat in the bed and making it pretty uncomfortable in the middle of the night.

2. Gel-Infused.
This is the same as the standard visco-elastic memory foam above, but now infused with gel beads and/ or gel liquid.

The infusion of gel makes the memory foam more breathable and its cells more open, allowing air to ventilate through the material. More air ventilation = less buildup of heat = a more comfortable sleeping experience!

With all things in life, however, there is a trade-off: whilst gel-infused memory foam mattresses regulate heat better, they could also make the foam material slightly more firm.

Within these 2 categories you can find memory foam mattresses that have also been infused with certain extracts to reduce odor, retain freshness, maintain a clean surface for your body to sleep on, or any combination of those three. Here are a few:

Aloe Vera: These memory foam mattresses simply have their mattress covers treated with aloe vera extract to promote healthy, protected skin as well as a cleaner sleeping surface. They come in visco or gel-infused varieties.

Green Tea Extract: Memory foam mattresses typically come with a not-so-pleasant memory foam smell that can permeate an entire room for the first few days after opening. Instead, you can opt for a memory foam mattress (visco or gel-infused) infused with green tea extract, which maintains a fresh smelling sleeping experience from the get-go.

Activated Charcoal. Similar to green tea extract, these memory foam mattresses are great at maintaining a fresh, non-intrusive smell. The added benefit of activated charcoal is the ability to aid in odor control and provide antibacterial protection.

Density and Firmness: Two Very Important Metrics

Ever since memory foam mattresses became popular with mainstream consumers, mattress companies have fought tooth and nail to get an edge over each other. Countless times this has resulted in the development of trademarked technologies, performance metrics and other standards of excellence that may not actually be as indicative of true quality as you would be led to believe. IFD (sometimes called ILD) is one of these performance indicators. We won’t bore you with the details, but long story short, don’t base your entire decision-making process on it. There have been studies conducted which proved that mattresses with similar or equal IFD’s had very different comfort levels.

Instead, there are two extremely important factors that you should definitely pay attention to, as they will better determine the firmness and comfort level of your future mattress, as well as how much you will potentially pay: density and firmness.


Density, when discussing memory foam mattresses, is a measurement of how much support the mattress will provide. It is measured in pounds per cubic foot, and refers to how much 1 cubic foot of foam material weighs. Here’s why it’s super important.

A less dense mattress:

  • Costs less.
  • Provides less support.
  • Sinks/ falls more.
  • Is less durable.

A more dense mattress:

  • Costs more.
  • Provides more support.
  • Is heavier.

Most importantly though, density is NOT an indicator of firmness – it’s an indicator of the level of support.

You will find memory foam densities ranging from 2 lbs – 5 lbs, but here’s a piece of advice: don’t buy a mattress with a density less than 3 lb. Opt for 3 lbs or greater every time, because most mattresses of less than 3 lbs density run a real risk of having to be replaced in just 3-5 months after purchase.


Firmness, on the other hand, is determined by the layer structure of the mattress.

Memory foam mattresses are made up of several layers of foam material, each with different densities:

The memory foam layer is typically the top layer, with a foam density ranging from 2 lbs – 5 lbs and a thickness of 1” to 4”. You have to pay very careful attention to thickness; the lower the thickness, the more firm the sleeping experience. Typically we recommend a 3”- 4” layer to maximize comfort without making the mattress too soft.

The middle layer is the next layer down, and is more dense than the memory foam layer. Allow at least 2” here.

The base support foam layer is the last, and arguably one of the most important layers in a memory foam mattress. Over time, the top layers of a memory foam mattress tend to sink, but as long as the base support layer is dense enough, you won’t feel yourself sinking too low.

Do You Need a Box Spring with a Memory Foam Mattress?

Short answer: No.

Long answer: Good memory foam mattresses will feel comfortable no matter what surface you place them on (as long as the surface is not uneven). This is why it’s so important to invest in high quality material (further detail on this below).

In the event that you wish to raise the height of your bed, you can definitely use a box spring mattress or other platform bed so long as it’s well ventilated.


And The One Costly Mistake…

Are You Really Purchasing High Quality Memory Foam?

Over the past few years, there have been a flood of new memory foam mattress products entering the market. Most of these new products are not only quite cheap, but also of mediocre quality and potentially harmful. For most first-time (and even many repeat) buyers of memory foam mattresses, it is super easy to make the mistake of purchasing a mattress from one of these brands. This is because while the naïve buyer is preoccupied by comparing the density and firmness of a selection of mattresses, they are completely neglecting to research where the respective mattresses are produced.

Without knowing where the mattress was made, any comparison of density, firmness, etc is completely useless.

So how are we supposed to know which of these hundreds of mattress companies are the real deal? I’m glad you asked, because the answer is actually pretty simple…

Zen Sleeping’s Initial Checks

1. Where was the memory foam mattress produced?

Memory foam mattresses produced in the USA and Sweden are held to very high standards of quality. Don’t expect the same standard of quality if the mattress you’re looking at was imported from China.

2. Is the manufacturer listed on the CertiPUR-US site?

CertiPUR-US is an independent organization in the USA which analyzes memory foam mattress products, judging manufacturers on 6 major factors. Memory foam mattresses that are CertiPUR-US certified are typically the best quality mattresses that money can buy.

3. What is the actual thickness / density of the memory foam layer?

Just because a mattress company tells you the memory foam layer is 3 inches, doesn’t necessarily mean it’s true (especially if this company fails points 1 and 2 above). To ensure the density is actually what they claim it to be, read our reviews.

4. What is the actual thickness of the foam in the supporting layers?
Same as point 3, but for the supporting layers.

Bonus Section: The Zen Sleeping Scoring System

When browsing through the site, you may notice that we utilize a point system to score the products we review. It’s called the Zen Sleeping Scoring System, and is quite simple and effective. It is designed to provide the most informative and well-rounded review for a product whilst also saving our readers time.

We normally start off our product reviews with a bang: by showing a product score out of 10. This gives our readers a good idea of how well we rate this product, as well as a “quick n’ dirty” breakdown of the score based on 5 equal factors. These 5 factors are then discussed in depth in the review, and consist of:

1. Initial Checks – 20 points
These are the same initial checks as above: where was the foam produced, is the manufacturer CertiPUR certified, etc. Each check is worth 5 points, for a total of 20.

2. Feel & Firmness – 20 points
I test this factor by discussing each layer of the mattress in depth (material, thickness, density, etc) and also physically test the product myself to give an idea of how it feels. I also consult with verified purchasers of the product to get an idea of how the mattress feels to them, and whether anything changes to the mattress over time.

3. Smell – 20 points
Pretty simple – does the mattress smell? I normally test this myself, and deduct points based on how strong the smell is, how long the mattress needs to air out, etc.

4. Heat regulation – 20 points
How well does the mattress regulate heat? I test this factor myself by recording how hot the mattress feels during a period of sleeping on the mattress (sometimes 1 day, sometimes 1 week, sometimes longer). I then consult with verified purchasers to gauge their opinions as well.

5. Value – 20 points
I consider all factors together in this section and give a score out of 20 that reflects how good a value I believe the mattress to be for a prospective buyer.

We then tally up these points at the end of each review, and give a score out of 100. That score, divided by 10, gives you the product score you see in the beginning of each review.

Time to Check Out Some Reviews

You’ve now been armed with the knowledge to judge between different memory foam mattresses. To put your newfound skills to good use, check out some of our memory foam mattress product reviews. Or if you’d rather go for the quick kill, check out our latest comparison tables. Stay zen, happy mattress hunting, and we wish you endless nights of sleep to come!