Guides · 9 min read

How to measure a wall for a desk that is not there yet

The desk on the card is 48 inches wide, and the wall is 50. Whether that is a fit depends on the trim, the outlet, the chair and the door, and none of them is in the photograph. Here is the order to measure in, and the two inches that catch most returns.

The desk on the card is 48 inches wide. The wall, by eye, is about 50. That gap of two inches is where most desk returns live, and it is not because the card lied: it is because a wall is never 50 inches of usable wall. It has trim at one end, an outlet at knee height, a door that swings into it and a chair that has to get out from under the desk without hitting the bed. None of that is in the photograph, and all of it is in your room. Below is the order to measure in, with a tape, before you press anything.

Measure the wall from trim to trim, then subtract

Stand at one end of the wall and run the tape to the other, from the face of the door trim or the corner to the face of the next trim or corner, at the height the desk top will sit, about 30 inches off the floor. Write that number down. Now subtract. A baseboard heater takes its length plus six inches of air. A radiator takes its width plus the pipes. A window that opens inward takes the swing of the sash. An outlet that the desk will cover is fine, but an outlet the desk will half-cover is a plug you can never remove, so count its faceplate as an inch of wall. What is left is the wall you have.

From that figure take two more inches. One is for the chair: a five-caster base rolls out at an angle, and a desk that ends flush with the door trim gives the chair a corner to catch on. The other is for the cable. Every desk on our shelves has a cable coming down behind it, most have a grommet, and a top that touches the wall on both ends leaves the plug nowhere to go but the middle. A 48-inch desk therefore wants a clear 50, and a 63-inch desk wants 65. If the wall you have is 49, the 47-inch desk with drawers and a hook is the one to read next, not the 48.

Depth is the number the alcove forgets

An alcove is measured twice: its width, which everyone measures, and its depth, which nobody does until the desk is in it. Our small computer desks are 15.7 to 19.7 inches deep, and the electric standing desks 24. A 20-inch-deep desk in a 22-inch alcove leaves two inches behind it for the cable and nothing in front of it for a chair, because the alcove walls are where the chair arms hit. In an alcove, the desk should be shallower than the recess by the cable and the chair should stand outside the recess entirely; a chair that lives inside an alcove is a chair you cannot swivel.

Depth also decides where the monitor goes, and OSHA has a number for that: the screen should be straight in front of you and at least 20 inches from your eyes. On a 15.7-inch-deep desk the monitor at the back edge is closer than that, and the fix is a monitor arm that reaches back past the edge, or a deeper desk. On the 24-inch-deep standing desks the screen sits at the back edge and the keyboard in front, which is the layout OSHA draws.

Height is not on the wall, it is on your elbow

The desks on our shelves stand 29 to 30.6 inches at the top, which is the height the industry settled on a century ago for a person of average height sitting on a chair with no adjustment. OSHA's rule is better: your forearms should be roughly parallel to the floor when your hands are on the keyboard, with your elbows bent between 90 and 120 degrees. Sit on the chair you will use, let your arms hang, bend the elbows to a right angle, and measure from the floor to the underside of the forearm. That is your desk height. If it is 27, a 30-inch desk will lift your shoulders all day, and a chair that raises you is the cheaper fix than a lower desk.

If it is 40 while standing, that is the argument for the electric desks, which run from 28.7 to 46.5 inches at the touch of a button and hold the two heights you set in memory. OSHA's longer sentence about posture is the one that decides between a fixed desk and a rising one: working in the same posture for a long time is not healthy however good the posture, and the cure is to change position, stand and walk. A desk that rises makes that a button rather than a decision.

The door, the stairs and the carton

A desk arrives in a carton longer than its top and heavier than the desk, because the steel frame is in there too. A 63-inch desk arrives in a box around 66 inches long, and a 67-inch L-shaped gaming desk arrives in two. Measure the narrowest thing between the front door and the room: the door itself, the turn at the top of the stairs, the width of the hallway at the radiator. A 66-inch carton turns a 36-inch-wide staircase landing on its end, upright, and only if the ceiling above the landing is higher than 66 inches. Where we state the carton on the page, read it against that turn; where it does not, allow the top plus three inches.

The door also swings. A desk placed on the wall a door opens against is a desk the door hits, and the chair rolled back from it is what the door hits first. Open the door fully and mark where its edge stops on the floor; the desk and the chair both belong on the far side of that mark.

A corner is two walls, and both need measuring

An L-shaped desk turns one problem into two. Measure from the corner outward along each wall, at desk height, to the first thing that stops you: a window frame, a closet door, a radiator. The long arm of our L-shaped desks runs 39 to 67 inches and the return 29 to 47, and each is printed on the card, so the question is whether the long arm fits the longer wall and the return fits the shorter one with two inches to spare on each. The return is the number people forget, because it is the arm that is not in the photograph from the front, and it is the one that ends up against the closet door.

Most of our L-shaped desks are reversible, which means the return goes on the left or the right at assembly and you decide by which wall is shorter. The ones with a fixed drawer unit are one-handed, and the card says which hand. Draw the corner on paper with both measurements before you read the cards; a sketch takes a minute and shows the closet-door problem before the carton does.

What to do with the two inches

Once the desk is in, the two inches you left are for the cable and the chair, and they are also where a power strip lives. OSHA's other desk rule is about the space under the top: it is for your legs, not for the computer tower or a box of paper, and a desk with a CPU shelf puts the tower where your knees go unless the shelf hangs outside the leg space. The 50-inch reversible desk puts its shelf at the far end of the long arm for that reason. Keep the floor under the desk empty, keep the strip on the wall behind it, and the desk that fit the wall on paper will fit the wall in the room.

The desk on the card is 48 inches wide, and the wall is 50. Whether that is a fit depends on the trim, the outlet, the chair and the door, and none of them is in the photograph.

The measuring order, once more

• Wall from trim to trim at 30 inches off the floor, then subtract the heater, the radiator, the window swing and any outlet the desk half-covers.
• Two inches off for the chair and the cable: a 48-inch desk wants a clear 50.
• Alcove depth against the desk depth on the card, with the chair standing outside the recess.
• Floor to the underside of your forearm, sitting and standing, against the desk height or the electric range.
• The narrowest door, landing and hallway against the carton, or the top plus three inches.
• For a corner, both walls from the angle outward against the long arm and the return, with two inches spare on each.