Sealy Ortho Support Small Double Mattress
The Sealy Ortho Support Mattress is available in five UK sizes, from Single up to Super King.
- Extra-firm feel for a flat surface
- Reinforced edges for more usable space
- Hypoallergenic fibre fillings
£615
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Sealy Ortho Support Mattress
More available sizes
Mattress details
Mattress
Sealy Ortho Support Mattress
Size
Firmness
Extra Firm
Construction
Orthopaedic
Depth (cm)
Layers
3
Layer Details
PostureTech 2.0 spring core
Sealy's PostureTech 2.0 smart spring core, made up of pocket springs individually encapsulated in fabric, forms the base of the mattress. It gives the firm support you would expect from an extra-firm build.
EdgeGuard surround
EdgeGuard surrounds the spring system and reinforces the sides and edges. That means you get more usable sleep surface, so you can sleep or sit nearer the edge without it feeling weak.
OptiForm extra-firm foam
A double layer of OptiForm extra-firm foam sits on top of the springs and gently cushions and adapts to your body. Expect a firm, fairly flat feel rather than a deep sink-in one.
Layer details from mattressman.co.uk product page, October 2026.
Key benefits
- Real space for one: At 120cm wide, this small double gives a lone adult genuine room to sprawl, turn over and change position without hanging an arm off the edge.
- Fits where a double won't: It's 15cm narrower than a UK double, which can be the difference between a door that opens fully and one that clips the bed frame.
- A sensible upgrade from a single: A teenager who has outgrown a 3ft bed gains 30cm of width here while the room keeps its floor space, since the length stays the same at 190cm.
- Works for guest rooms: Visiting couples can share it comfortably for a few nights, so it suits a spare room or holiday let where nobody sleeps in it permanently.
- Standard 4ft sizing: The small double is an established UK size, so finding a frame and small double fitted sheets is straightforward.
This size suits you if...
You sleep alone and want more room than a UK single offers, perhaps in a box room, studio flat or loft conversion where every centimetre of floor matters. It also fits if you're furnishing a guest room or rental second bedroom where couples stay occasionally rather than nightly, or you're downsizing and the bed has to suit the new room rather than the old one.
Consider another size if...
You share the bed with a partner every night, in which case 120cm gets cramped quickly. We'd recommend the UK double instead, which is 15cm wider and needs a room of at least 2.6m x 2.8m.
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FAQ's
What room size do I need for the Sealy Ortho Support in a small double?
We suggest a room of at least 2.4m x 2.8m for a UK small double. That allows space to walk around the bed and open drawers or a wardrobe. If your room is tighter than that, a UK single needs at least 2.1m x 2.8m and may be the more liveable choice.
Is the small double Sealy Ortho Support big enough for a couple?
For occasional nights, yes. Two adults can share 120cm of width comfortably enough for a weekend stay, which is why the small double is a popular guest room choice. For nightly sharing, most couples find it restrictive, and the UK double or UK king of this mattress would serve you better.
Will a small double fit in a loft conversion or box room?
Often, yes, and that's a large part of its appeal. At 120 x 190cm it leaves standing room where a 135cm double would run tight against sloping ceilings or a door swing. Measure the usable floor area first: we suggest a minimum of 2.4m x 2.8m for this size.
Is the Sealy Ortho Support small double the same length as a single?
Yes. Both the UK small double and the UK single are 190cm long, so upgrading only changes the width, by an extra 30cm. That makes it a natural step up for a teenager or solo adult who has outgrown a single but can't give up much floor space.
What's the size jump from this small double to the UK king?
The UK small double is 30cm narrower and 10cm shorter than the UK king. If you're a taller sleeper or share nightly, the king's extra length and width make a real difference, but it needs a room of at least 2.7m x 2.9m, which many compact bedrooms can't offer.