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The Complete Mattress Coil Guide: Why Are Coil Gauge, Coil Count, and Coil Types Important?

Updated: May 6, 2023

Did you know that 8 out of 10 US homes have an innerspring mattress, making it the most common type on the market? The innerspring mattress features a core made from metal coils that give it its unique bouncy feel.

Innerspring mattresses have been around since the 19th century, but a lot has changed since then. Today’s models have become more supportive and comfortable while having a longer lifespan.

So, why are today’s mattresses so much better?

Two words – superior coils.

In this article, we cover everything you need to know about coil gauge, coil count, and coil types to find the perfect innerspring mattress for your bedroom.

Let’s dive in!

What Are Mattress Coils?

Mattress coils are metal springs that provide the support of the innerspring mattress. These coils are typically made of steel that goes through the tempering process, which enhances durability.

Mattress coils are designed to flex when you lay on the mattress and return to their regular position when you get up. This design ensures proper support for the spine and body during the night.

Innerspring mattresses are affordable and provide a great mix of comfort and support. In fact, the versatility of mattress coils makes them great, which is why some hybrid models also have a coil-support base.

Now, let’s see how factors like coil types, coil gauge, and coil count affect the quality and sleeping experience.

Why Is Mattress Coil Gauge Important?

The coil gauge defines the thickness of a metal wire used to create mattress coils. A smaller number represents a thicker gauge. So, a 13-gauge wire is bigger than a 15-gauge wire.

So, why is that important?

Well, coil gauge directly affects how firm a mattress feels. Most experts agree that a 14-gauge is ideal for most sleepers because it provides an excellent mix of support, durability, and comfort.

However, some sleepers could benefit from a lower or higher coil gauge. For example, heavier individuals or sleepers who prefer a firmer mattress can benefit from a lower coil gauge (12-13).

If you’re on the lighter side or prefer to sleep on your side, aim for a higher coil gauge (14-15).

How Does Mattress Coil Count Affect Durability?

Coil count represents the number of coils used in a mattress. You typically want a higher coil count because it contributes to the overall support and durability. However, more is not always better, as a gauge, coil type, and other factors also impact the quality of your sleeping surface.

The exact number of coils used in a mattress can vary based on the manufacturer, coil type, and mattress size. However, our general recommendation is that the coil count should be at least 300 for a full-size mattress, 400 for a queen-size, and 480 for a king-size.

Mattresses with low coil counts may not provide good support and deteriorate more quickly. That’s why it is vital to look at the coil count if you want to get a quality mattress that will last a long time.

Mattress Coil Types

Most manufacturers recognize the four types of mattress coils with many variations. So, let’s go over these four and see the advantages and shortcomings of every kind of coil.

Bonnell Coils

Bonnell coils feature an hourglass shape that allows good overall support. The thinner part flexes with a small amount of pressure, whereas the top and the bottom respond to heavy pressure. That’s why this type of mattress coil is suitable for sleepers of all shapes and sizes.

Bonnell coils have been around the longest and are the most basic of all coil types. They are usually connected together to ensure better stability and durability. However, this also makes for poor motion isolation, which is why Bonnell coil mattresses are not ideal for people who easily wake up when their partner changes position.

Innerspring mattresses with this coil type are often noisy and less durable than other options. Because of that, they are a good option for guest rooms where they won’t be used every night. In addition, you can put a Bonnell coil mattress in your kid’s room because the chances are they will outgrow it in a few years.

The main benefit of Bonnell coils is a cheap manufacturing process that ensures these mattress models stay affordable.

Offset Coils

If you’re looking for a twist on the traditional Bonnell coils, offset coils are also shaped like an hourglass but have square bases and a hinge. This provides better support, motion isolation, and superior contouring abilities.

Although offset coils are interconnected with a wire, the unique hinged design allows better motion control and durability. That’s why offset coils are a great option if you’re looking for a new mattress for your bedroom.

Lastly, the hinged design of offset coils helps them contour to the sleeper’s body. This reduces pressure points, providing better support and comfort.

Continuous Wire Coils

Unlike other types, continuous wire coils are created from a single piece of metal wire bent into interconnected helical shapes. This unique pattern provides a strong foundation, which is why mattresses with this type of coils are typically more durable.

However, the downside is that mattresses with continuous wire coils are usually noisy and transfer motion easily. Because of that, they are not a good fit for light sleepers who share the bed with their partner.

The biggest advantage of continuous wire coils is that they offer excellent support for an affordable price. In addition, these mattresses are durable and won’t wear down quickly, even with everyday use.

Pocket Coils

Now we come to the king of all coils – the pocket coil. Pocket or Marshall coils feature metal springs enclosed in little pockets of fabric. This unique design allows pocket coils to flex independently, which enables better support and comfort.

Since the pocket coils flex when you lay directly on them, the mattresses with this support system have the best contouring properties of all innerspring models. Because of that, pocket coils can help your spine stay in a neutral position throughout the night, providing superior pressure point relief. As a result, you may finally get to wake up without feeling any back pain.

Because pocket coils can absorb pressure relatively independently from one another, these mattresses offer better motion isolation. So, if a typical innerspring mattress seems too bouncy or squeaky, the pocket coils can overcome these complaints.

Which Coil Type is Best for a Mattress?

If you’re looking for the combination of targeted support, pressure point relief, comfort, and durability, pocket coils are the best option. That’s why we use pocket coils at Custom Mattress Factory to craft some of our custom mattresses.

Pocket coils are also an excellent option for co-sleeping because they are less noisy and provide better motion control than other coils.

So, if you are interested in a custom mattress with pocket coil support, make sure to visit our online store and get a fully-personalized model.


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