Sealy Harlow Ortho Plus Mattress
Mattress
Sealy Harlow Ortho Plus Mattress
Size
Firmness
Firm
Construction
Depth (cm)
26
Layers
2
Layer Details
- Comfort Layer. Soft white fibre fillings sit at the surface to cushion the hardest parts of the body, which means your hips and shoulders get a little give before reaching the firmer support below. It's a traditional filling with a slightly springier feel than foam.
- Support System. PostureTech Core Support Springs use unique shapes and varied tension across the mattress, which means fuller support where your body presses hardest and pressure relief where it doesn't. This is the layer doing most of the orthopaedic work.
Layer details from mattressonline.co.uk product page, September 2026.
- A shared bed that fits the room: At 135 x 190cm, the UK double leaves space for wardrobes and drawers in a typical bedroom, with bedside tables on both sides usually still possible.
- Defined space for each sleeper: Two people sharing get 67.5cm each, and the firm PostureTech springs keep you supported on your own side rather than rolling together.
- Modest room requirement: We suggest at least 2.6m x 2.8m, which means most second bedrooms and first flats can take this size without the bed dominating.
- Firm support without flipping: It's single-sided at a firm feel, so a couple never needs to wrestle a double mattress over to rotate it edge to edge.
- Easy to dress: Standard double sheets and duvets fit the UK double and are stocked everywhere, handy if you're furnishing a whole home and budgets are stretched.
- A practical guest room size: Visiting couples sleep comfortably on a firm UK double, and it suits a guest room that also needs to hold storage.
This size suits you if...
You share the bed every night and want a firm, supportive feel in a size your bedroom can actually take, or you're kitting out a first flat or guest room and need a bed for two that still leaves room for a wardrobe and drawers. It also suits a solo back or front sleeper who likes space to spread out, even with a dog or cat claiming a corner.
Consider another size if...
You're both broad-shouldered or restless and 67.5cm each feels tight, or you're over 6ft 3in. The UK king is 15cm wider and 10cm longer; we'd recommend it if your room allows at least 2.7m x 2.9m.
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Is the Sealy Harlow Ortho Plus in a UK double big enough for a couple?
For most couples, yes. The UK double gives two people sharing 67.5cm each, and the firm PostureTech springs hold each of you on your own side rather than letting you sink towards the middle. If either of you is broad or a restless sleeper, that width can feel a little snug, and the UK king is 15cm wider.
What room size do I need for the Sealy Harlow Ortho Plus double?
We suggest at least 2.6m x 2.8m for the UK double. That allows walking space around the bed and, in most rooms, bedside tables on both sides. Measure with your wardrobe and drawers in place before deciding: if the room is comfortably bigger than that minimum, the UK king may also be an option.
Should I choose the Sealy Harlow Ortho Plus in a UK double or UK king?
It comes down to your room. The UK double is 15cm narrower and 10cm shorter than the UK king, so it suits bedrooms where a king would dominate. We suggest at least 2.7m x 2.9m for the UK king. If you have that space and share every night, the extra width is genuinely useful; if you don't, the UK double is the better fit.
Is the UK double Sealy Harlow Ortho Plus suitable for a guest room?
It's a good match. A firm orthopaedic feel suits occasional use by back and front sleepers, and the 135 x 190cm footprint fits a guest room that also holds storage. Visiting couples get a proper shared bed, and standard double bedding keeps dressing it cheap and simple. Lightweight side-sleeping guests may find the firm feel a little unyielding.
How big is the Sealy Harlow Ortho Plus double in feet and inches?
It measures 4ft 6in x 6ft 3in, which is 135 x 190cm. That's the same length as the UK single and UK small double, so if you're replacing either of those the bed won't extend further into the room, only across it: the UK double is 45cm wider than the UK single and 15cm wider than the UK small double.