Harrison Spinks Grassington 5750 Pocket Mattress
Mattress
Harrison Spinks Grassington 5750 Pocket Mattress
Size
Firmness
Medium Firm
Construction
Depth (cm)
28
Layers
2
Layer Details
- Comfort Layer. 100% natural Yorkshire wool blended with cotton, flax and hemp fibres. These wick away moisture and regulate temperature, which means less overheating than you'd get from synthetic fillings.
- Support System. 5,750 pocket springs, a mix of traditional pocket springs and mini springs, each encased in breathable cloth pockets using Harrison Spinks' Cortec Quad Core spring system. Each spring moves independently, so you feel support where your body needs it rather than a uniform push back.
Layer details from mattressonline.co.uk product page, September 2026.
- Space to sleep, not negotiate: With 75cm each for two people sharing, you can both change position without the nightly territorial dispute a double often becomes.
- Independent springs, quieter nights: Each of the 5,750 springs moves on its own, which means an early alarm on one side transfers less across the bed.
- Length for taller sleepers: At 200cm long, the UK king is 10cm longer than the UK double, so feet stop hanging off the end for anyone nearing six foot.
- Cool across a wider surface: The wool, cotton, flax and hemp fillings wick moisture and regulate temperature, useful when two bodies are warming one mattress all night.
- Firm support at couple width: The medium to firm feel keeps you both level rather than rolling into a shared dip in the middle.
This size suits you if...
You share the bed every night and a double has started to feel like a compromise, or one of you keeps odd hours and you'd rather their comings and goings didn't wake the other. It also makes sense if either partner is approaching six foot, since the extra length here is as valuable as the extra width.
Consider another size if...
Your bedroom is smaller than the 2.7m x 2.9m we suggest for a UK king. In that case the UK double would suit you better, and it needs slightly less room: we suggest at least 2.6m x 2.8m.
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Is the Grassington 5750 in a UK king good for couples?
Yes, and it's arguably the size this mattress makes most sense in. You get 75cm each for two people sharing, and because all 5,750 springs move independently, one partner shifting or getting up disturbs the other less than on a traditional sprung double. Lightweight sleepers who like a soft, sinking feel may still find the medium to firm tension too solid.
What room size do I need for the UK king Grassington 5750?
We suggest a room of at least 2.7m x 2.9m for a UK king, which leaves enough space to walk round the bed and open drawers. In a newer build master bedroom, measure after you've accounted for wardrobes, as the usable floor space is often less than it first appears.
Is the UK king long enough for a tall sleeper?
At 200cm, the UK king is 10cm longer than the UK double, which is often the difference between comfortable and cramped for anyone around six foot. If you're taller still, the UK super king is the same length as the UK king, so at that point the gain is width rather than legroom.
How heavy is the Grassington 5750 in a UK king?
Harrison Spinks doesn't publish a weight for this size, but a 28cm pocket spring mattress with natural fillings at 150 x 200cm is a heavy item. Owners note it's a struggle to handle alone, so plan for two people when rotating it, and check access to your bedroom before ordering.
Should I choose the UK king or the UK super king in this mattress?
The UK king is 30cm narrower than the UK super king, and both are the same length. If your room meets the 3m x 2.9m we suggest for a UK super king and you want maximum personal space, size up. If space is tighter, the UK king remains the more practical fit for most couples.