King size Murphy beds — The size where the mechanism stops being cheap
The Wooden Stars is a participant in the Amazon Services LLC Associates Program. We may earn a commission when you buy through links on our site, at no extra cost to you.
A king Murphy bed is the point where the category stops being a clever space-saving trick and becomes a piece of engineering. A US king mattress is 76 inches wide and 80 inches long, and it weighs roughly twice what a twin does. Every part of the bed has to answer for that.
That is why the king is the size where the price jumps, where the choice of models narrows sharply, and where getting the fixing wrong stops being a cosmetic problem.
A king Murphy bed needs a wall over 76 inches — more than six feet of uninterrupted run — and 80 inches of clear floor in front of it, permanently. Vertically mounted it stands about 80 inches tall closed, so it also needs real ceiling height. Expect to pay considerably more than a queen, because the lift mechanism is sized to mattress mass and a king mattress is the heaviest thing in the category. Choice is limited: far fewer models exist at this size, and California king is rarer still. Check the mattress thickness limit before you buy the mattress.
The three measurements, at king scale
The same three numbers govern every Murphy bed, but at king size two of them become genuinely hard to satisfy in an ordinary room.
- Wall width. 76 inches of mattress plus the cabinet sides — call it seven feet of wall with nothing in it. No light switch, no door swing, no radiator, no window reveal. In most rooms this is the number that kills the idea.
- Clear floor. 80 inches out from the wall, and it has to stay clear rather than be clearable. Same as a queen; the length does not grow with the width.
- Ceiling height. Roughly 80 inches closed on a vertical mount, plus swing clearance above that. A standard eight-foot ceiling is 96 inches, so this usually works — but a basement or a sloped attic ceiling will not.
Why it costs so much more
The price gap between a queen and a king Murphy bed is wider than the gap between a full and a queen, and it is not the manufacturer being opportunistic. Three real costs stack up.
The lift mechanism
Gas pistons and torsion springs are rated to a weight range. A king mattress plus a king platform is at or beyond the top of the range used on smaller beds, so the mechanism is a different, heavier part — often two pistons per side rather than one. This is the single biggest line item.
The cabinet structure
A 76-inch-wide cabinet spans further between its sides than any other size, so the top and the platform both need more material or more reinforcement to avoid sagging. Thin panel that is adequate on a twin is not adequate here.
The volume of production
Fewer people buy king wall beds, so there are fewer models, fewer factories making them, and less price competition. The cheap end of the market that exists at twin and queen size mostly does not exist here.
| Size | Mattress | Wall needed | Clear floor |
|---|---|---|---|
| Full | 54 × 75 in | Over 54 in | 75 in |
| Queen | 60 × 80 in | Over 60 in | 80 in |
| King | 76 × 80 in | Over 76 in | 80 in |
| California king | 72 × 84 in | Over 72 in | 84 in |
Note the California king row. It is narrower than a standard king and four inches longer, which means it needs less wall and more floor. Cabinets are built around one mattress size, so a standard king cabinet will not take a Cal king mattress and vice versa. Very few Murphy beds are made for Cal king at all — if that is the mattress you own, check availability before you plan the room.
The fixing is not negotiable at this size
Every wall bed puts load into its anchors, because the mechanism turns the mattress into a lever. At king size that lever is carrying the most mass in the category, and the consequences of a bad fixing are correspondingly worse.
Studs, into the manufacturer’s specified points, with the manufacturer’s fixings. Drywall anchors are not an alternative at any size and are an outright hazard at this one. A 76-inch cabinet will cross four or five studs on standard 16-inch centres, and you want all of them, so a stud finder is the first tool for the job rather than an optional convenience.
If the wall is masonry, the fixings change entirely and you want the manufacturer’s guidance rather than a generic anchor. If the wall cannot take it, the honest answer at king size is that there is no freestanding equivalent — cabinet beds top out at queen.
The mattress limit, which bites harder here
Every cabinet states a maximum mattress thickness, because the mattress folds into the case with the bedding on it. King mattresses tend to be the thick, pillow-topped kind, so the clash between what people own and what the cabinet accepts is more common at this size than any other.
Buy the cabinet, read its number, then buy the mattress. There is no fix in the other direction except a new mattress, and a king mattress is an expensive mistake.
Vertical or side-mount at king size
A side-mount king is an unusual animal. Closed, it stands about 76 inches tall — barely lower than the 80 inches of a vertical king — and it runs 80 inches along the wall. You give up four inches of height and gain nothing worth having.
The reason is arithmetic: a king mattress is nearly square, so rotating it barely changes anything. Side-mounting pays off on a twin, where 75 × 38 becomes 38 × 75, and it is pointless on a king. The mechanism and its real uses are covered in side-mount Murphy beds.
What the cabinet is made of
On a king this is a structural question rather than a longevity one. The load points where the mechanism bolts into the case see the highest forces in the category, and a wide span invites sag in the top and the platform.
Solid timber and good plywood hold a screw and keep holding it. Particleboard enlarges its hole under repeated load and cannot be repaired well. Most cabinets use engineered panel somewhere, which is fine — what matters is whether the load points are reinforced and where the board sits. The listing vocabulary is decoded in what engineered wood actually is.
Is king the right size at all
Worth asking plainly, because the wall requirement is brutal. If the room is being converted between bedroom and something else, the extra 16 inches over a queen costs you 16 inches of wall that the room may need for a door, a desk or a wardrobe.
The queen is the sweet spot of the category: most models, best prices, 60 inches of wall. Go king only if two adults sleep in it regularly and the wall genuinely exists. If the room is tight, start from measuring the room before the bed instead.
Before you order
- Stud finder A 76-inch cabinet crosses four or five studs and you want all of them
- Tape measure Wall run first — it is the number that decides whether king is possible
- Spirit level A wide cabinet shows any error in plumb across its whole width
- Mattress retention strap A king mattress is the heaviest in the category; the strap earns its keep
What to buy
If the wall will not take 76 inches, price the queen before compromising elsewhere. The four sizes are set side by side in Murphy bed sizes, and the mechanics of the whole category are in how Murphy beds work.
Questions we get asked
Do they make king size Murphy beds?
Yes, but far fewer models than at queen size, and the cheap end of the market is thin. California king is rarer again.
How much wall does a king Murphy bed need?
Over 76 inches — about seven feet once the cabinet sides are counted — with no switch, door swing or radiator inside that run.
Why are king Murphy beds so expensive?
The lift mechanism is sized to mattress mass, the cabinet has to span 76 inches without sagging, and far fewer are made. All three push the same way.
Can a king Murphy bed be side-mounted?
Mechanically yes, but there is little point. A king is nearly square, so rotating it saves only about four inches of height while costing four inches of wall.
Will a California king mattress fit a king Murphy bed?
No. A Cal king is 72 × 84 inches against the standard king’s 76 × 80 — narrower and longer. Cabinets are built around one mattress size.
How much floor space does a king Murphy bed need when open?
Eighty inches out from the wall, the same as a queen. Length does not increase with width; only the wall requirement does.
