Foam encapsulated mattresses work by encasing the inner mattress fillings within a supportive foam border. Essentially, foam encapsulation is a "box" of support foam that reinforces the whole mattress. This outer foam border helps to improve mattress durability, reduces the likelihood of sagging and prevents a feeling of "roll-off".
In summary, foam encased mattresses include the following key features:
Additionally, foam encapsulated mattresses may also feature a layer of support foam above the springs. This acts like a "lid" and ensures the mattress surface is well supported.
A comfort layer made from memory foam, latex or gel foam - and a cover - completes the mattress. Whilst it's possible to find foam encapsulation within a wide range of mattresses, this mattress construction technique is most often found in hybrid mattresses containing memory foam and pocket springs.
Foam encapsulation is a mattress construction method where high-density foam borders support the mattress core. This offers several practical benefits that can contribute to comfort and durability in the following ways:
The reinforced foam border helps reduce wear and tear to maintain the shape and structure of the mattress over time. It can reduce the risk of sagging, especially around the edges, and can prolong the lifespan of the mattress.
The foam encapsulation supports the sleeper better when they are sitting or sleeping near the edge. It holds the internal support system, usually pocket springs, in place, preventing it from moving or shifting, and creating a more uniform feel across the whole mattress.
Sleeping space is maximised with edge-to-edge support, which is especially important if you share a bed with a partner.
Learn about the benefits of foam encapsulation in this video from Sealy:
A foam encapsulated mattress is typically made from reflex foam, a type of polyurethane foam known for its firmness and quick recovery properties. This high-density foam surrounds the mattress's internal support system (often pocket springs). It provides structural reinforcement, and helps to reduce edge sagging and maintain the mattress's shape over time.
If you'd like to read more about reflex foam, check our advice page, 'What Is a Reflex Foam Mattress?'.
As with all mattress types, there is a great variety of foam encapsulated mattress designs. "Foam encapsulated" simply refers to the high-density foam support border; many encapsulated mattresses feature pocket springs or open coil springs (also known as standard springs) and an additional comfort layer.
This comfort layer is most commonly found on top of the foam "box". There are many different comfort fillings available, and each will affect the overall feel, comfort and support of your mattress in different ways.
Responds to body heat and movement, conforming closely to the sleeper’s shape for enhanced pressure relief.
Also known as reflex foam, high-density foam offers quick bounce-back and helps to maintain a supportive sleeping surface over time.
No, you don't need to turn this type of mattress. Foam encapsulated mattresses are single-sided due to the reflex foam base and encasement. Making them easier to care for and maintain. You only need to rotate your encapsulated mattress from end-to-end - we recommend doing this once every three months. This may be helpful for those who prefer a low-maintenance mattress design.
For more information about keeping your mattress in great condition, you might like to read our advice page about how often you should rotate or turn your mattress.
Foam encapsulated mattresses are available across a wide range of price points, depending on factors such as the type of springs used, the quality of comfort layers, and overall construction. While some might assume that foam encapsulated mattresses are higher in cost, their durability makes them more cost-effective over time. The mattress edges and sleeping surface are less vulnerable to sagging and also help maintain the mattress's structure, which may contribute to a longer lifespan.
That was a quick introduction to foam encapsulated mattresses — a supportive design that helps improve edge stability, reduce sagging, and maximise usable sleep area.
If you’re interested in exploring mattresses that feature foam encapsulation, here are some types where this is commonly found:
To learn more about these options, visit our mattress guides or browse mattresses with foam encapsulation.
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