What a threshold really is
A threshold is less a wall than an agreement. In a Japanese house the genkan, a step down by the door, tells you where outdoor shoes stop. A shoji screen lets light through while saying that this part of the room is private. Eileen Gray's E1027 villa of 1929 used screens and built-in furniture to divide living space without closing it. Le Corbusier's Cabanon, a single room of 3.66 metres square, was zoned by its cupboards and its bed alcove.
The lesson for a studio is to give each zone one clear cue, and only one. A rug and a screen and a change of paint and a lamp, all in the same corner, say the same thing four times. One well-chosen cue lets the eye relax.
Five cues, one at a time
A rug as a floor plan
A rug is a drawn rectangle: sofa legs on its edge, a coffee table at its centre, and the sitting room exists.
Note: choose a size so that at least the front legs of every seat rest on it; 160 by 230 cm suits many studios.Open shelving as a half-wall
A cube bookcase with an open back, set at right angles to the wall, divides bed from living area while letting light pass.
Note: anchor it to the floor or wall, and keep heavy objects on the lowest shelves.A ceiling-track curtain
A linen curtain on a track that you draw at night and ignore by day. It is the closest thing to a door that a studio can have.
Note: a lined or double-layer curtain also dampens sound; hang it a few centimetres off the floor.A painted rectangle
A single deeper shade, painted behind the bed or the desk as a panel, marks a zone without building anything.
Note: check your tenancy first, and use removable wallpaper panels if painting is not allowed.A pool of light
A lamp low in a corner tells the room where evening happens. See the lighting chapter for the practical details.
Note: warm bulbs, 2700 to 3000 K, suit sleeping and sitting areas.
Furniture that faces away
A sofa with its back to the bed is the oldest divider of all. Add a narrow console behind it and you have a place for keys, a lamp and a plate of fruit, and a boundary the eye respects. A desk that faces the wall, rather than the room, ends the working day visually: you turn your chair and you are no longer at work.
One cue per zone, and then let the room breathe.
A plan to try this weekend
Draw the room on paper at roughly 1:20, marking the door, window, radiator and sockets. Name three zones: sleep, sit, work, and add cooking and eating only if they are not already obvious. Place one cue per zone, live with it for a week, and note what annoys you. Then adjust. The best layouts are found by walking through them, not by looking at them.
A last note on proportion: keep the main walking route at least 75 cm wide, and keep it unbroken from door to window. A zone that blocks the route is not a zone but a hurdle.