5ft King Size Mattresses

5ft King Size Mattresses: The Ultimate Buying Guide

A 5ft king size mattress offers a generous sleeping surface for couples and individuals who prefer more room, with the added benefit of extra length compared with a standard double. Measuring approximately 5ft x 6ft6 (153cm x 200cm), it's a popular choice for master bedrooms, taller sleepers and couples looking for more personal sleeping space.

Beyond size, the construction of a mattress determines much of its comfort and character. Spring systems, foam and natural fillings, firmness, edge support and the bed base underneath all contribute to the finished sleeping experience. Understanding these features can make comparing king size mattresses considerably easier.

1. King Size Mattress Dimensions

A standard UK king size mattress measures approximately 5ft x 6ft6 (153cm x 200cm). This provides additional width and length compared with a standard double mattress.

The mattress dimensions shouldn't be confused with the overall dimensions of the bed. Upholstered side rails, headboards and footboards can make a bedstead considerably larger, while a divan base generally follows the mattress footprint more closely.

When replacing an existing mattress, measure the internal sleeping area of the bed. When buying a completely new bed, use its full external dimensions when planning the available bedroom space.

2. Comparing King Size with Double and Super King

A 4ft6 Double Mattress measures approximately 4ft6 x 6ft3 (137cm x 190cm), compared with 5ft x 6ft6 (153cm x 200cm) for a king.

The move from double to king therefore adds around 16cm of sleeping width and 10cm of length. That extra length can be particularly useful for taller sleepers, while couples gain additional personal sleeping space.

A 6ft Super King Mattress measures approximately 6ft x 6ft6 (183cm x 200cm). King and super king mattresses are therefore the same approximate length, but the super king provides around 30cm of additional width.

3. Understanding Mattress Firmness

Firmness describes the sensation of the sleeping surface rather than simply how supportive a mattress is. A mattress can have a substantial supporting spring system while still providing soft cushioning through its upper comfort layers.

Our range includes Soft Mattresses, Medium Mattresses, Medium-Firm Mattresses and Firm Mattresses.

• Soft: Greater cushioning with more initial sink into the comfort layers.
• Medium: A balance of cushioning and a supportive sensation.
• Medium-Firm: A more supportive feel while retaining noticeable cushioning.
• Firm: A more solid sleeping surface with less initial sink.

Firmness remains subjective. Body weight, sleeping position, mattress construction and the type of bed base underneath can all change how the same mattress feels to different sleepers.

4. Pocket Sprung King Size Mattresses

Pocket Sprung Mattresses contain individual springs enclosed within separate fabric pockets, allowing different areas of the mattress to respond more independently to pressure.

This construction is particularly relevant to larger mattresses shared by two people. Each sleeper applies pressure to the mattress differently, and independently moving springs allow the sleeping surface to respond more individually across its width.

Spring count is only one part of the specification. The spring design, wire gauge, arrangement of the springs, upholstery and comfort layers all contribute to the overall feel and performance of the mattress.

5. Memory Foam and Foam Comfort Layers

Memory Foam Mattresses use pressure-responsive foam designed to contour around the body.

Memory foam can form the main comfort material in an all-foam mattress or be combined with a sprung support system. Different depths and densities of foam create different sleeping characteristics, so the presence of memory foam alone doesn't tell you how soft or firm a mattress will feel.

Other specialist foams may be designed to provide quicker response, additional airflow or a different level of cushioning, making it useful to compare the complete comfort-layer construction.

6. Hybrid King Size Mattresses

Hybrid Mattresses combine different mattress technologies within one construction. A typical hybrid may combine pocket springs with memory foam, gel foam or other specialist comfort layers.

The aim is generally to combine the responsive support of springs with the cushioning properties of foam. However, hybrid is a broad category rather than one particular mattress specification.

Two hybrid mattresses can feel completely different depending on their spring system, foam composition, comfort-layer depths and firmness, so compare what's actually inside the mattress rather than choosing on the hybrid name alone.

7. Cooling and Temperature Management

Mattress manufacturers use a variety of materials and construction methods intended to encourage airflow and manage sleeping temperature.

Cool Gel Mattresses can incorporate gel-infused or specialist cooling comfort layers, often alongside foam or pocket springs.

Other mattresses may use breathable covers, ventilated foams, open-cell structures or natural fibres. As cooling technologies differ considerably between manufacturers, it's useful to look at the complete construction rather than relying on a single cooling feature.

8. Natural Mattress Fillings

Natural Mattresses can incorporate materials such as wool, cotton and other natural fibres within their upholstery.

These fillings are frequently combined with pocket springs to create traditionally upholstered mattresses and are valued for properties such as cushioning and breathability.

Natural content varies considerably between products. Some mattresses contain several substantial layers of natural upholstery, while others use natural materials as part of a wider blend of fillings. The individual specification will show what's actually included.

9. Orthopaedic and Firmer Mattress Designs

Orthopaedic Mattresses are generally associated with a firmer, more supportive sleeping sensation.

Orthopaedic isn't a single mattress construction. Different products can use open coil springs, pocket springs, foam or combinations of materials, so the term should be considered alongside the actual firmness and construction of the mattress.

A firmer feel also isn't automatically the right choice for every sleeper. Personal comfort remains an important part of selecting a mattress.

10. Rolled King Size Mattresses

Rolled Mattresses are compressed and rolled to make transportation and handling more convenient.

Rolled packaging isn't limited to basic foam mattresses. Depending on their construction, pocket sprung and hybrid mattresses can also be compressed for delivery.

Once unpacked, the mattress should be allowed to expand according to the manufacturer's instructions before normal use.

11. Features Worth Comparing for Couples

The additional width of a king size mattress makes it particularly attractive for couples, but the internal construction can be just as important as the extra space.

Independent spring movement can help different areas of the mattress respond separately when one sleeper moves. Edge support can create