Harrison Spinks Byron Mattress
Mattress
Harrison Spinks Byron Mattress
Size
Firmness
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.
- The traditional couples' size: At 135 x 190cm, the UK double is the long standing standard for two sharing, which means it fits most UK bedrooms without dominating them.
- Room for bedside tables both sides: In a room of at least 2.6m x 2.8m, our suggested minimum, a UK double usually leaves space for a table each side of the bed.
- Firm support across a shared surface: Seven layers of micro and Cortec pocket springs respond to each sleeper separately, which means you feel little of your partner's movement even at 67.5cm each.
- Easier seasonal flipping than the larger sizes: The Byron needs turning between its winter and summer sides, and a UK double is a more manageable flip than the wider UK king or UK super king.
- Simpler delivery in older homes: A 135cm wide, 29cm deep mattress is easier to turn on the tight stairs of a terrace or a narrow new build landing than the larger sizes.
This size suits you if...
You share the bed every night and your bedroom sits around the typical UK size, comfortably fitting a 135 x 190cm mattress but not a UK king. It also suits a solo sleeper who wants generous space to spread out, or someone who shares with a dog or cat that claims a corner, and who wants the Byron's firm, natural feel in a room-friendly footprint.
Consider another size if...
You and your partner both want more personal space than 67.5cm each, and your room measures at least 2.7m x 2.9m. In that case we'd recommend the UK king instead, which is 15cm wider and 10cm longer.
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What are the dimensions of the Harrison Spinks Byron in a UK double?
The UK double measures 135 x 190cm, or 4ft 6in x 6ft 3in. Two people sharing get 67.5cm of width each. The mattress itself is 29cm deep across every size, so allow for that when buying fitted sheets, which need a deep-wall design to stay put.
How much space does each person get on a UK double Byron?
Two people sharing get 67.5cm of width each. That's the traditional couples' allowance in the UK, and the Byron's 13,060 pocket springs help it feel calmer than the number suggests, because each side responds to its own sleeper with very little movement crossing the middle.
Will the Byron in a UK double fit a smaller bedroom?
Usually, yes. We suggest a room of at least 2.6m x 2.8m for a UK double, which covers most UK bedrooms, including second bedrooms and first flats where a wardrobe and drawers also need floor space. Measure with walking room and door swing in mind, and check the space either side if you want bedside tables.
Is the UK double Byron difficult to flip?
The Byron has a wool-rich winter side and a cotton summer side, so it needs turning twice a year. At 135cm wide it's a two-person job given the depth and natural fillings, but noticeably easier to handle than the UK king or UK super king. If flipping any large mattress is a struggle for you, that's a fair reason to hesitate.
Should I buy the Byron in a UK double or size up to the UK king?
If your room measures at least 2.7m x 2.9m and you'd both value more space, the UK king is 15cm wider and 10cm longer, a real difference for restless sleepers or anyone sharing with a pet. In a typical UK bedroom, the UK double keeps space for furniture and is easier to deliver and flip. Compare the retailers listed on this page for both.