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
| Measurement | How to take it | Why it matters |
|---|---|---|
| Height | Floor to highest point, with feet or castors attached | Decides stacking and whether it stands upright in the unit |
| Width | Widest point including arms and handles | Compared against the door opening |
| Depth | Front to back at the deepest point | Decides how far it eats into a narrow unit |
| Diagonal depth | Top back corner to bottom front corner, in a straight line | The real constraint when tilting a sofa through a door |
Record all four for anything you would be upset to leave behind.
Where each measurement is taken
The diagonal is marked in amber because it is the one that gets skipped. Height, width and depth describe the piece; the diagonal describes whether the piece can be moved.
Worked example: a three-cushion sofa
Say the tape gives 84 in wide, 38 in deep and 34 in tall.
- Bounding box. 84 × 38 × 34 = 108,528 cubic inches, ÷ 1,728 = 62.8 cu ft.
- Published packed value. 50 cu ft. The box overstates a sofa, because the space above the arms takes other things.
- Diagonal depth. √(38² + 34²) = √2,600 = 51 in.
- The verdict. A 4–5 ft wide roll-up door is 48 to 60 in of opening. At 51 in diagonal this sofa will not pass the narrow end of that range, and at 84 in wide it cannot be turned inside a 5 ft unit at all.
Two numbers, one decision: the volume said a /storage-unit-sizes/5x10/ might do, and the tape said it cannot. The tape wins.
The items that decide the unit width
These are the pieces the size model refuses to place in a five-foot-wide unit whatever the volume arithmetic says, because they cannot be turned once inside:
| Item | Packed volume | Typical weight |
|---|---|---|
| King bed set | 75 cu ft | 300 lb |
| Upright piano | 70 cu ft | 500 lb |
| Sofa bed / sleeper sofa | 60 cu ft | 350 lb |
| Riding mower | 60 cu ft | 450 lb |
| Sofa, 3-cushion | 50 cu ft | 250 lb |
| Armoire / wardrobe | 45 cu ft | 220 lb |
| China cabinet / hutch | 40 cu ft | 190 lb |
| Sectional piece | 30 cu ft | 150 lb |
| Treadmill | 30 cu ft | 220 lb |
| Dining table | 30 cu ft | 130 lb |
| Kayak / paddleboard | 25 cu ft | 55 lb |
| Workbench | 25 cu ft | 120 lb |
| Patio table | 20 cu ft | 70 lb |
Values are the published packed volumes from the 95-item dataset. If your list contains any of these, filter the size chart to units at least 10 ft wide before comparing capacity.
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
Related questions
What is diagonal depth and why does it matter?
Once measured, convert your own measurements converts your dimensions to cubic feet and storage unit sizes 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.