What's Inside a Mattress?

Mattresses are made up of a number of layers. All mattresses contain a:

support layer
comfort layer
cover

These layers can contain a variety of materials, all designed to offer you a comfortable and supportive sleeping surface.

The support layer

The support layer is the main part of your mattress. This section gives your body the support it needs, and is the main contributor to how firm your mattress is.

The support layer is usually made up of either springs or foam, or both.

Springs

The majority of mattresses contain springs. Springs are the metal coils within your mattress, which provide support for your body as you sleep.

There are two main categories of spring systems which are used within mattresses. These are either a standard sprung system, also known as an 'open coil' or 'bonnell' system, or a pocket sprung system.

Foam

Where foam is used within the support layer, this is a high-density foam called reflex foam. Some mattresses are comprised only of foam, without springs.

All-foam mattresses are a type of non-sprung mattress, made up of layers of different densities of foam.

As there are no springs, foam mattresses tend to be lighter than sprung mattresses, enabling these mattresses to be more easily manoeuvred.

In addition, due to the high-density nature of foam, mattresses made only of foam are often naturally hypoallergenic, since they offer very little opportunity for dust mites to settle within the mattress. Because of this, foam mattresses can be a good option for those who suffer from allergies.

The comfort layer

The comfort layer makes up the first few inches of the mattress surface. This layer can be made up of a variety of materials of varying depths, designed to offer you a luxurious, cushioned sleeping surface.

These materials are all designed to offer you the ultimate in comfort, and depending on the mattress can include:

memory foam
latex
gel-infused foam
natural fillings such as cotton, wool or silk
soft white fibres

Each type of material within the comfort layer will have different properties and benefits.

For further information on the types of materials found in the comfort layer, we have advice sections on memory foam, latex, gel foam and natural fillings.

Cover

The cover of the mattress is exactly that - the material used to cover the mattress.

There are two main types of covers: damask and knitted. They can vary quite significantly in terms of touch and functionality.

Damask covers

These covers provide a soft finish that's extremely hard wearing. Made from a woven material that is more often than not patterned, damask is a popular choice that offers great breathability.

Knitted covers

As the name suggests, this type of cover is knitted, using a soft-touch fabric with elasticated properties. This cover is almost always used for mattresses that include memory foam or latex, moving as the foam moves. It's also used often in other types of mattresses as well. Again, this type of cover offers excellent breathability.

Cover finishes

Covers are then either quilted, tufted or may be plain, without a finish.

Quilted

Sometimes referred to as "micro-quilted", this type of finish is made by stitching the cover to the comfort layer. This creates a pattern on the top of the mattress. The ultimate in luxury, this type of cover offers supreme softness.

Tufted

Covers, and the mattress itself, can also be tufted. Tufted mattresses ensure that the mattress fillings remain in place and usually give the mattress a slightly firmer feel. This helps to ensure a good level of support for your body.

Plain

The cover can sometimes be left alone, without any tufting or quilting. This type of cover can often be found on rolled-up mattresses.

Special features

Covers often have special features:

Body temperature-regulating

Some covers can cool you down if you're too hot or warm you up if you're too cool! They absorb moisture and can store heat, releasing this when your body needs warming up as you sleep. They are often are hypoallergenic and breathable.

Look out for these brands on the product pages:

Tencel
Coolmax
Cocona
Hydraflex

Removable

Some covers are removable so they can be cleaned easily. Usually these types of covers are dry-clean only. Always refer to manufacturer guidelines for further information.