Harrison Spinks Byron Mattress
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Mattress
Harrison Spinks Byron Mattress
Size
Firmness
Firm
Construction
Pocket Spring
Wool
Natural
Depth (cm)
29
Layers
4
Layer Details
Top surface
Generously layered with 100% natural cashmere, mohair, cotton, hemp, flax and British wool. This is the winter side, where insulating wool with silk absorbs moisture and helps regulate temperature, which means fewer clammy nights in colder months.
Fillings
Soft cashmere, sourced as a byproduct from the fashion industry, brings insulation and a supremely gentle surface feel. It sits alongside traceable British sheep's wool from the British Wool partnership.
Springs
13,060 responsive springs across seven layers of high-density micro and Cortec pocket springs, which means very precise, localised support. The Cortec system is glueless and 100% recyclable.
Reverse surface
A breathable cotton side designed for summer use. Flip the mattress with the seasons to get the right sleeping temperature year round.
Layer details from featherandblack.com product page, September 2026.
- Space that ends the elbow wars: At 75cm each for two people sharing, you can both change position freely without negotiating territory in the small hours.
- Early alarms stay on one side: The pocket springs respond locally rather than as one slab, so a partner leaving hours before you gets up without dragging you awake.
- Extra length for taller sleepers: The UK king is 10cm longer than the UK double at 200cm, a genuine relief if either of you is approaching six foot.
- Natural fillings across a wider surface: Cashmere, wool, silk and cotton regulate temperature for both sleepers, useful when one of you runs hot and the other doesn't.
- Fits most master bedrooms: We suggest allowing at least 2.7m x 2.9m, which most UK master bedrooms can manage without the squeeze a super king demands.
This size suits you if...
You share the bed every night and a double has started to feel cramped, especially if one of you gets up much earlier than the other. It also suits couples where one partner is tall, since the 200cm length removes that dangling-feet problem. And if a dog has quietly claimed a share of the mattress, the extra width absorbs that too.
Consider another size if...
Your bedroom is under our suggested 2.7m x 2.9m minimum, or you sleep alone. We'd recommend the UK double instead, which needs at least 2.6m x 2.8m and keeps the same length and construction.
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Is the Harrison Spinks Byron UK king big enough for two people?
Comfortably, for most couples. At 150 x 200cm, that's 75cm each for two people sharing, and the 13,060 springs keep each sleeper's movement on their own side. If one of you sprawls, or a pet shares the bed most nights, the UK super king adds another 30cm of width.
Is the Byron in a UK king long enough for someone over 6ft?
Yes, and length is often the overlooked reason to size up. The UK king is 10cm longer than the UK double at 200cm, which means someone around or above six foot can stretch out fully. The UK super king is the same length, so going bigger again only buys width, never extra length.
What room size do I need for a UK king Byron?
We suggest at least 2.7m x 2.9m, with more feeling noticeably better once wardrobes and bedside tables are in. New build master bedrooms can be tighter than they look on the plan, so measure with furniture in place. If the room falls short, the UK double needs at least 2.6m x 2.8m.
Is the Byron hard to flip in a king size?
It takes some effort. Harrison Spinks doesn't publish a weight for this size, but a 29cm deep, 150cm wide mattress with dense natural fillings is a two-person job. Since the Byron flips seasonally between its winter and summer sides rather than monthly, plan for two flips a year with help on hand.
Where can I compare prices for the Byron in a UK king?
Use the live table on this page. The prices shown here are updated as retailers change them, so it's a more reliable picture than any figure written into the text. This is a luxury mattress at every size, so comparing before you commit is sensible even if the retailer list is short.