Mattress comparison and opinions

What are the best type of springs in mattresses? Comparison Guide



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Best types of mattress springs

Mattress springs come in all shapes and sizes, which means in some cases they will compress and move in different ways. We’ll check out the various kinds of springs that you may find in an innerspring or pocket-sprung mattress and see what they bring to a mattress. 

Bonnell coils

These coils are the traditional springs in innerspring mattresses. They are hour-glass shaped, with knotted wiring and in the common Bonnell spring system, they are connected to two metal meshes which are beneath and above the coiled network. They are the first type of coil to be introduced to mattresses and due to the mass-production and cheap manufacturing procedure of innerspring mattresses, they are the most prevalent type. To learn more about innerspring mattresses and how they contribute to the history and market of mattresses, check out the link.                                         

They are known for their durability and the coils tend to be made with a mixture of a high and low gauge, with the higher gauge parts designed for the responsive quality in the spring system, reacting to pressure upon it and the low gauge parts there to ensure the springs can bear great amounts of pressure. These coils offer sufficient support and edge support, but as the Bonnel units are almost always interconnected the mattress is typically made up of one single metallic mesh frame which means it does not have the contouring qualities of micro-coils for example and will have a very low amount of motion isolation 

Marshall Coils

These are springs that are pocketed by a textile and respond independently of other springs in the system. They were the smart idea of James Marshall who invented them in 1899, hence the coil’s name, which he used to start his own mattress company. He wanted to improve on Heinrich Westpal’s use of steel coils in the innerspring mattress which was a single unit and allow for suspension of the body to be based on the individual pressure exerted on each coil.

Marshall coils used in mattresses, in production

 Their individualization ensures a high level of pressure point relief which is why  pocket-spring mattresses often perform much better than innerspring mattresses in this aspect. The encased coils are stitched or glued together, but not stuck together in a way where each coil would not have the freedom to respond on its own. They are of a cylindrical shape which makes them great at absorbing force. Their wiring is high-gauge and often specifically of an even higher gauge in areas where certain pressure relief is required more like the hips and lumbar region. This level of gauge means it is highly adaptable and will compress even with slight pressure. Despite being high-gauge, due to their design, they are less susceptible to being worn down than the hourglass-shaped Bonnell springs. Another evolutionary advantage that Marshall coils have over Bonnell coils is that they are usually used in a spring system with a higher coil count than the average Bonnell coil mattress. This means that it is likely to give you better support. 
As every coil is wrapped, Marshall coil mattresses normally are more expensive than innerspring Bonnell coil mattresses. The Dreamcloud Luxury Hybrid Mattress is an excellent example of a mattress that uses Marshall coils to great effect. You can check out the mattress here.

Dreamcloud Luxury Hybrid

The verdict

The Dreamcloud Luxury Hybrid is an excellent choice for a lot of stomach sleepers and back sleepers and is up for contention for being the best mattress for those that finds themselves in such a sleeping position. It really acts as a dream cloud bed. Its high level of firmness brings a lot of support to the matress.  The Activedge spring technology ensures there is no slack on the outer edges of the mattress, so mass is more evenly distributed than in mattresses where this isn't the case.  Furthermore it is composed of gel memory foam which is one of, if not, the leading technology in heat dissipation within mattresses.  This mattress ticks a lot of boxes as revealed in this Dreamcloud Luxury Hybrid mattress review.

Our grading of the Dreamcloud Luxury Hybrid

Dreamcloud Logo
Dreamcloud Luxury Hybrid

A luxurious, yet practical mattress that combines numerous layers to excellent effect assessed in this Dreamcloud mattress review

4.5 / 5
star star star star
Best types of mattress springsHalf star image

Dreamcloud Luxury Hybrid : Pros and Cons

We appreciate

  • You are a light to average weighted stomach-sleeper 
  • You are a sleeping couple who are  sensitive to motion elsewhere on a mattress.
  • You sweat quite a lot when you sleep and need a cover to remove moisture as well as keeping you cool
  • You need assistance with spinal alignment and can’t afford any back problems created during your sleep. 
  • You sometimes end up sleeping on the edge of a mattress

We regret

  • You are side-sleeper of about an average weight or less. For you, as your mattress advisor, we recommend the Nectar mattress which will provide appropriate pressure-relief for you in this sleeping position.
  • You want  a high level of viscoelastic adaptability in your mattress. For this we recommend the memory foam mattress,  Emma original 

Continuous coils

These are coils that are constructed with a curve that resembles the ‘S’ shape. Usually, a Continuous coil system is made up of single, continuous, helical wires stretched horizontally, which are connected to single, curved wires stretched vertically. 

Best types of mattress springs

Since the coils are interconnected they are not appropriate for motion isolation, with movement being shared across the springs. The continuous coil system predates the Marshall which coil was an upgrade in the pressure relief that it offers. The name Mira-coil is a branded system of continuous coils and was created and trademarked by the mattress company Silentnight beds after they produced a continuous-coil system under another name in 1986.    
Continuous-coil offers a high degree of comfort due to the distribution of pressure across the spring system. Its design makes it more durable. Continuous coil systems usually use high-gauge wires which contribute to the mattress being lightweight and easy to move about and the coils in the system usually are heat-tempered which toughens the coils


These are very small coils that are enwrapped in a fabric or foam material much like Marshall coils, but on a tinier scale. The metal wiring has a high gauge. 


 ‘High gauge means of a low thickness or being very thin, whilst low gauge means very thick’. 

If you would like to know more about what gauge is and how it affects some pocket-spring mattresses check out the link.

They are designed for bringing support to the mattress and springiness which won’t come as much of a surprise. However what may come as a surprise is that they usually do not, unlike most innerspring mattress coils, make up the core of the mattress beneath the comfort layer. Instead, they are usually used in the comfort layer itself. This is because they are smaller, thus distributing pressure amongst their individual components better than most innerspring coils and they are sheathed with soft materials, so they are more comfortable than the majority of innerspring coils. In fact, these factors make it possible for them to match latex and memory foam in terms of the comfort they offer. Therefore micro-coils can be slept directly on without it feeling like you are actually sleeping on coiled metal.  
They are usually from 1 to 3 inches wide, but some have even been produced which are a fraction of a centimeter in width. The smaller forms of micro-coils are further subdivided into mini-coils and nano-coils. These basically function in the same way, but are even smaller.

 When micro-coils are used in innerspring coils, they generally are used as a layered system with the smaller coils at the top, to replicate the upholstery and core configuration in other innersprings. 

Micro coils tend to be great when it comes to air circulation when they are used in the upper layers of the mattress since numerous air pockets exist in the design. This promotion of airflow keeps you cool when you’re sleeping and even performs better than memory foam when it comes to temperature moderation. 


Dreamcloud Luxury Hybrid

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The mattresses that you’ll find them in


Often they’ll be found in hybrid mattresses with the innerspring part of the mattress being a fixed part of hybrids using mini-coils whilst the other part can be latex or memory foam.

Bonnell coils

They are the cornerstone of innerspring mattresses.

Best types of mattress springs

Marshall coils:

These are also known as pocket coils which indicates that if you come across Marshall coils there is a high chance that it will be in a Pocket-coil mattress. However, they are also used in hybrid mattresses such as the Dreamcloud Luxury Hybrid.

Continuous coils: 

They  are typically in open-coil mattresses. 

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