Measure the narrowest point on the route before you measure the room. Almost every failed furniture delivery is stopped by a doorway, a stair turn or a lift door rather than by the floor area, and a secondhand piece that will not fit is yours to keep and yours to pay for twice.
The order matters. Route first, room second, and the furniture last, because a tape measure is cheaper than a courier. Work through the front door, the hall, any turn, the stairs and the final doorway, and write down the narrowest figure at each point rather than the widest. For a sense of scale, the ADA Standards require accessible doorways to give a clear width of at least 32 inches, so a public doorway sets a rough floor; houses can be tighter.
The four measurements that decide a delivery
What to measure, and why the obvious figure is the wrong one
| Where | What to measure | Common mistake |
|---|---|---|
| Interior doorway | The clear opening with the door open, not the frame | Using the frame width, which is 2 inches wider than the gap you will pass through |
| Stairwell | Clear width, then the diagonal of the tightest turn | Measuring only the width, when the turn at the top or bottom is the binding constraint |
| Lift | The cab interior as well as the door | Assuming the door width is the limit when the cab depth stops a long piece |
| Room | Wall to wall, then door swing and radiator depth | Ignoring the 8 inches a radiator and its pipework take off the wall |
The diagonal is the number people forget
A rectangular piece can be tipped, so the opening it must pass through is judged against the cross-section it presents rather than its length. That is why a deep armchair is harder to get through a doorway than a long low sofa: the armchair presents a large square face, and the sofa presents a thin one. If the opening diagonal is smaller than the depth and height of the piece together, it will not go through at any angle.
- 1
Measure the narrowest doorway on the route
Open the door to ninety degrees and measure from the edge of the door leaf to the opposite jamb. Do the same at the building entrance and at any internal door.
- 2
Measure the stairwell at the turn
Then measure the diagonal across the tightest corner, and the headroom above it. A piece longer than the stairwell diagonal has to come through a window, which changes the price.
- 3
Measure the elevator and book the freight one
Cab interior and door opening both. A building with a freight elevator is a different delivery from one without, and the booking usually has to be made in advance.
- 4
Mark the footprint on the floor
Painter tape does this in five minutes with no drawing. It shows if you will still be able to open the doors and reach the windows.
Then measure the room properly
- Walkway first, furniture second — A main path needs about 36 inches and a secondary path about 24. Mark those two lanes with tape before you place anything, then see what is left.
- Note the fixed objects — Radiators and their pipes, window sills, floor vents, socket positions, the door swing arc and any cupboard doors that open outwards. Each one takes real space off a wall.
- Check the ceiling, not just the floor — A tall bookcase needs clearance to be tipped upright, and pendant lights and ceiling roses decide whether it can be. Measure the height at the wall, not in the middle of the room.
- Measure the thing you are replacing — The old piece that fits is a free answer. If a sofa of a given depth worked in the room for years, the replacement should not be more than a few inches deeper.
Six tools that pay for themselves on one delivery
Together they cost less than a single failed sofa delivery. Prices are shown only where we confirmed them on the brand or retailer page in Oct 2026.
Start hereKomelon
Self-Lock Tape Measure, 25 ft
A 25 foot blade covers a whole room, and the lock means the measurement does not collapse while you write it down.
Check price
Bosch
GLM 50-27 CG Laser Measure
For anything above head height or behind a sofa the laser is quicker and more accurate than a blade, and it stores a running total for a whole room.
Check price
Stanley
Stud Finder 150
Relevant to the shelving question rather than the doorway one, and the tool most often borrowed and never returned. Buy one if you plan to hang anything heavy.
Check price
SuperSliders
Reusable Furniture Sliders, 8 pack
Useful on the day: sliding a heavy piece across a floorboard is far safer than dragging it, and the sliders prevent the scrape that costs you a deposit.
Check price
General Tools
Door Pin Punch Set
The single cheapest way to gain width on a tight delivery. Take the door off, move the sofa, put the door back, and nobody will ever know.
Check price3M
Painter's Tape, 1.88 inch
Cheaper than a floor plan app and more honest, because it shows the space a thing actually takes up including the bit you cannot see. Never leaves a mark on a sealed floor.
Check priceWhat getting it wrong costs
A return delivery on a new sofa can cost a few hundred dollars, and on a secondhand piece there is no return at all: you have bought it, you have paid for the failed delivery and you are paying again to have it taken away. A long piece that will not turn on a staircase usually has to come through a window, which means hiring a hoisting crew, at real cost.
