How to measure furniture for storage

Measure each large item's height, width and depth, plus its diagonal depth — the distance from the top back corner to the bottom front corner, which is what determines whether it fits through a doorway when tilted. Then measure the storage unit's door opening, which is always narrower than the unit itself.

  • 4 measurements per item
  • Diagonal depth is the one people miss
  • Door opening ≠ unit width

The four measurements that matter

MeasurementHow to take itWhy it matters
HeightFloor to highest point, with feet or castors attachedDecides stacking and whether it stands upright in the unit
WidthWidest point including arms and handlesCompared against the door opening
DepthFront to back at the deepest pointDecides how far it eats into a narrow unit
Diagonal depthTop back corner to bottom front corner, in a straight lineThe real constraint when tilting a sofa through a door

Record all four for anything you would be upset to leave behind.

Measuring the unit, not just the furniture

Advertised unit dimensions are nominal. A "10x10" measured inside the walls is frequently 9 ft 6 in by 9 ft 8 in, and the roll-up door is narrower again — typically 8 ft on a 10 ft unit and 4 to 5 ft on a 5 ft unit.

Before you sign, ask for or measure: the door opening width, the door opening height, the interior ceiling height, and the corridor width if the unit is interior. That last one ends more moves than the unit size does — a long sofa that fits the unit may not turn the corner to reach it.

Items that catch people out

  • Sofas over 7 ft. Will not turn inside a 5 ft wide unit in any orientation.
  • King mattresses. 76 in wide; they go in on edge or not at all.
  • Refrigerators. Measure with the doors on. Removing them buys about 3 inches and a lot of trouble.
  • Dining tables. Take the legs off. It recovers 15–20% of the volume and makes them stackable.
  • Treadmills. Fold and measure folded, but check the folded height against the door.
  • Armoires and tall bookcases. Height plus ceiling clearance in the corridor, not just in the unit.

Turn the measurements into a size

What is diagonal depth and why does it matter?

Once measured, measure your furniture in cubic feet converts your dimensions to cubic feet and every standard unit size shows which unit clears the total. Diagonal depth is the straight-line distance from the top back corner of a sofa to the bottom front corner. When you tilt furniture to get it through a doorway, that diagonal — not the depth — is what has to clear the opening.

How wide is a storage unit door?

Typically 8 ft on a 10 ft wide unit and 4 to 5 ft on a 5 ft wide unit. Always narrower than the unit, and worth confirming at the specific facility.

Should I disassemble furniture for storage?

Yes for bed frames and tables — it recovers 15–20% of their volume and makes them stack. Bag and label the hardware, and tape it to the underside of the piece it belongs to.