What Size Bed Fits Your Bedroom?
The rule we use in the studio: bed width, plus 60–70cm of walking space on each open side. A double (135cm) is comfortable on a wall run of about 2.6m; a king (150cm) wants about 2.8m; a super king (180cm) about 3.1m. Everything else on this page follows from that arithmetic.
Keep this page open while you measure. It holds the wall-run arithmetic for every UK size, the legal minimum bedroom sizes for new homes, and the four-minute test that settles the question for good — worth sending to whoever shares the room before either of you decides.
The wall-run cheat sheet
| Bed | Mattress | Wall run, comfortable both sides | Workable, one side to the wall |
|---|---|---|---|
| Single (3ft) | 90 × 190cm | ~2.1m | ~1.5m |
| Small double (4ft) | 120 × 190cm | ~2.4m | ~1.8m |
| Double (4ft 6in) | 135 × 190cm | ~2.6m | ~2.0m |
| King (5ft) | 150 × 200cm | ~2.8m | ~2.2m |
| Super king (6ft) | 180 × 200cm | ~3.1m | ~2.4m |
Measure the wall the headboard will sit against, not the room's longest side. Remember the frame: most bed frames add roughly 5–15cm over the mattress dimensions, more where the headboard is deep or strutted — a wall-mounted headboard recovers 8–12cm of that floor depth. Emperor beds (200cm wide) exist too; at that width the room is designed around the bed, which is commission territory.
The legal minimums, for reference
For new-build homes, the government's Nationally Described Space Standard sets the legal floor: a double bedroom must be at least 11.5 m² and the main double bedroom at least 2.75m wide (other doubles at least 2.55m); a single bedroom must be at least 7.5 m² and at least 2.15m wide. Older housing stock is not bound by this — which is exactly why so many older British bedrooms need a small double, or a bed built to the room rather than to the standard.
And the direction of travel makes the arithmetic matter more, not less: LABC Warranty's study of 10,000 British houses ("Are Britain's Houses Getting Smaller?", 2019) found the average new-build main bedroom fell from 15.34 m² in the 1930s to 13.37 m² in the 2010s — about 13% smaller. The bedrooms shrank; the wall-run sums above are how you win the space back.
The four-minute tape test
Mark the bed's width on the floor with masking tape — 135cm, then 150cm if you are deciding between two sizes. Stand in the taped rectangle. Open the wardrobe. Walk the route to the door. Four minutes, and it settles the question more reliably than any guide, including this one.
When the room refuses the standard
Loft rooms, sloping ceilings, chimney breasts, doors that open the wrong way, landings a standard frame will not turn on — these are not reasons to accept a smaller bed. They are the brief for a made-to-measure one: custom widths, bespoke heights, and frames designed around the room. Tell us about the room, including the awkward part.