You’ve researched and tested out beds, and you’ve come to the conclusion that an innerspring mattress is right for you. Luckily, determining the type of bed you’re looking for is probably the hardest decision in buying a mattress, and from here, you can start narrowing down your search.
Of course, you’ll want to look at mattresses that fit your desired firmness level, but did you know that you should also be looking at the coil count for any innerspring beds and that there are actually different types of coils that can affect your sleep? Don’t worry – we’ll go over all of this in more depth below.
What Are Mattress Coils?
Mattress coils are springs made out of steel located toward the bottom of a mattress for support, stabilization, and weight distribution. They are what give innerspring and hybrid mattresses their quintessential bounce.
Depending on the type, the coil can look slightly different, but generally, a mattress coil looks a bit like a metal slinky when it’s a little stretched out. It will then compress when weight is put on it.
The coil unit in an innerspring mattress is going to be the only real form of support since innerspring mattresses only include a coil unit and one comfort layer on top. This is why learning about the ideal number of coils, coil type, and coil gauge is so important.
Types of Mattress Coils
There are four different types of coils, each of which has certain advantages and disadvantages. We’ll briefly go over each below.
- Bonnell Coils – Bonnel coils are the classic innerspring coil. They first started being used in the 1800s for seat cushions in buggies, and then in the early 1900s were added into mattresses.With an hourglass shape and steel that curves around in a spiral, like a helix, Bonnell coils tend to be bouncy and durable. That said, they are also the most prone to sagging and potentially making noise when you change positions. These classic coils are a mid-priced option.
- Pocketed Coils – Also referred to as encased or individually wrapped, pocketed coils are typically found in hybrid mattresses, which are similar to classic innerspring beds but include more foam comfort layers on top and sometimes an additional foam base below the coils.With this system, each coil is individually wrapped in fabric, so they work independently of each other. This makes for a bed that has better motion isolation (so you will be less likely to feel your partner moving at night) and more contouring to the body. Mattresses with pocketed coils will likely cost a bit more.
- Offset Coils – Offset coils are a slightly more expensive option but well worth the price if you’re looking for a bed that won’t make a sound. They’re similar to Bonnell coils in that they’re hourglass-shaped, but the tops and bottoms of the coils have flattened edges. This makes the bed conform more to the shape of your body and have slightly less motion transfer than other innerspring options.
- Continuous Coils – Continuous coils are made from one long piece of wire to form the bed’s entire support system. Because the construction is simpler, mattresses with continuous coils have a lower price point but are still durable. Unfortunately, this one long piece of metal means that the motion transfer – when one person moves on the other side of the bed – might be more noticeable.
Coil Count and Coil Gauge
When you’re reading an innerspring mattress’ description you’ll probably come across two terms: coil count and coil gauge. Coil count refers to how many coils the mattress has.
As a general rule, the higher the coil count, the more supportive and durable the mattress will be. If you’re a lightweight sleeper, you probably won’t need as high of a coil count as somebody who weighs a lot. A higher coil count also usually makes for a firmer-feeling mattress.
As far as coil gauge goes, this describes how thick the coils are. It may seem counterintuitive, but the lower the gauge number, the thicker the spring is. This means that coils with a low gauge number are firm, supportive, and an ideal fit for somebody heavier who needs more support or wants a firmer mattress. These thicker coils also tend to be more durable over time.
Coils with a higher gauge number are softer and bouncier. They tend to work best for lighter-weight folks or those who want a softer bed. The mattress’s coil gauge number is usually somewhere between 12 and 15, where 12 is firm and supportive and 15 is the softest and bounciest.
Oftentimes mattresses use a combination of low and high-gauge coils across the mattress for different levels of support.
How Many Coils Should a Mattress Have?
Since the number of coils in the mattress has an impact on the support you’ll get and how long the bed will last, we don’t recommend beds with very low coil counts. At a minimum, you’ll want 300 coils for a Full-size bed, 400 coils for a Queen, and 480 for a King.
However, we recommend something closer to 800 coils if you’re an average-weight sleeper. This should be supportive enough for your frame, and the mattress won’t need to be replaced as quickly. If you are a heavier-weight person, something with more than 800 coils would be best.
If you’re looking for an innerspring mattress, knowing about the types of coils it includes, how many of them there are, and their gauge is essential. All of these factors will determine how supportive, firm, and durable the mattress will be.
To recap, more coils equal more support, and the lower the gauge, the thicker and firmer the coil. So, a bed with a coil count of 1,000 and coil gauge of 12 would be extremely firm and supportive, whereas a bed with a coil count of 300 and a gauge of 15 would be extremely soft and likely not all that supportive.
To help make things a little bit easier for you, we’ve gathered up a list of the best innerspring and hybrid beds. The coil count and gauge will vary from mattress to mattress, but all of these are excellent options.
Natalie is a content writer for Sleep Advisor with a deep passion for all things health and a fascination with the mysterious activity that is sleep. Outside of writing about sleep, she is a bestselling author, improviser, and creative writing teacher based out of Austin.