Mirror Placement Feng Shui: What the Reflection Shows

Every rule about mirrors comes out of a single mechanism. A mirror returns an image of whatever faces it, and an ordinary silvered mirror returns somewhere around 85 to 95 per cent of the visible light that reaches it, less whatever the glass and the frame absorb. It is not a light source and it does not add depth. A mirror facing a blank wall shows a blank wall.

That collapses the whole topic into two questions you can answer standing in the room. What is the mirror showing, and from where do you look at it? A mirror that shows a window, a garden or a room with depth is doing work. A mirror that shows a corridor, a doorway into a bathroom, or the foot of a bed is showing you something you will see again at the worst hour. Neither answer needs an inventory of cures.

This is the rule with the most folklore attached and the clearest physical basis. In a dark room the eye adapts over roughly 20 to 30 minutes, and a single bright patch resets most of that adaptation. A mirror at the foot of the bed sits in the one place where anything bright in the room — a street lamp through a gap in the curtains, a standby LED, a phone screen — gets folded back onto the bed at the mirror's angle.

The second effect is movement. A mirror facing the bed usually also faces the doorway, so anyone walking past the room registers at the edge of vision as motion in a place where nothing should be moving. Neither effect requires believing anything about energy, and both are testable in one evening: sit on the bed at the hour you sleep with the lights off, and look at the mirror. If there is a bright patch or a lit rectangle, you have found the problem, and the fix is to angle the mirror, cover it, or move the bed out of the reflected field — not to buy anything.

People hang a mirror opposite the front door for a good reason: it doubles the length of a narrow hall, which is exactly what a mirror does well. The cost is that you now meet your own arrival, and in low light a figure appearing in a doorway is startling even when it is you.

The other cost is at night. Stand in the doorway with the hall light off and look at the mirror. If it shows a bright rectangle — a window, a street lamp, a lit room behind you — that brightness lands in your eyes every time you come home after dark, and the adaptation you just spent the walk home building is gone. If the mirror instead shows the inside of the flat, the arrangement is doing what it was put there for and there is nothing to fix. When it does need changing, the order of preference is a side wall first, the same wall angled second, and a mirror inside a cabinet door third.

The first is light at the face. Shaving and makeup are close visual tasks, and the guidance for that kind of work sits roughly at 300 to 500 lux at the surface being looked at. It also has to come from the front. A single fitting directly overhead puts the eyes and the jaw in shadow, which is why a mirror with a light above it can be worse than the same mirror with two lights at the sides.

The second is moisture. A silvered mirror fails from the edges inward, because that is where moisture reaches the backing first, and a bathroom is the one room where the glass is wet on purpose. Running the extract fan during and after a shower does more for the mirror's life than any placement rule. If a mirror faces the bathroom door, the practical fix is a self-closing hinge on that door, so the interior is only on show for the seconds someone is using the room.

For standing use, the centre of the mirror wants to be around 150 cm above the floor, which puts most adults' head and shoulders in the glass without stooping. A full-length mirror needs glass up to roughly 170 to 180 cm and its bottom edge within about 20 cm of the floor, or you will be looking at your shoes and guessing about your hair.

Fixing is where this stops being a design question. Adhesive pads are rated for small, light mirrors on flat, sound surfaces. Anything over about a square metre, or anything mounted above 1.5 m, should be mechanically fixed into studs or masonry with fixings rated well above the mirror's weight, because the failure mode is a sheet of glass arriving at head height. Two rules that are not symbolic at all: nothing heavy above a bed, and nothing glass directly above a hob or a radiator, where heat cycling works on the adhesive and the backing.

Round, square, arched and octagonal are furniture conventions of the last century and a half, not classical prescriptions; the octagon belongs to the bagua mirror, which is an outdoor object with its own neighbour problem. Choosing a shape to match the room is a reasonable thing to do and needs no justification.

The one old rule that survives inspection is that a mirror should be whole. A crack or a patch of desilvering distorts the image, and a dark streak at the edge is where the reflective layer has gone, which spreads. That is a reason to replace the glass, not a reason to read the streak as anything.

Sort the placement by what the mirror is supposed to be showing, then check the failure mode that goes with it. Every row below can be checked in under a minute, and none of them requires knowing which way the room faces.

Before drilling, cover the mirror or change its angle for two weeks and write down the one thing you wanted to improve: glare, a startle, privacy, or a route you keep bumping into. Check that single thing at the end. If nothing changed, the mirror was never the problem and you can stop.

Two exceptions skip the trial. A cracked, loose or unusually heavy mirror is a physical problem and gets fixed first, whatever it is reflecting. And a mirror that has been doing a job well — doubling a dark hall, lighting a dressing corner — should be left alone even if a rule somewhere says otherwise; the rule and the room disagreeing is the room's business.