Dimensions and weight
internal dimensions
Internal dimensions are the length, width and height of the usable space inside a container. They are smaller than the outside size because of wall thickness, floor and roof structure. ISO 1496 is the authoritative document for internal container dimensions.
Why it matters
Inside size decides what fits. A carrier lists a dry 20-foot container at about 19 feet 4 inches long, 7 feet 8 inches wide and 7 feet 10 inches high inside. Builds vary a little, and the numbers are for reference. A common mistake is to plan from the outside size. Pallets, furniture and equipment need clearance on all sides. Another mistake is to forget the door opening, which is smaller than the interior. Measure the item against the interior and the door. Ask the provider for the actual dimensions of the unit you will get, and leave room for access, air flow and safe handling.
Read: Portable storage container sizes: What size do you need?
Definition source: one-line.com
Related terms
external dimensions
External dimensions are the length, width and height of a container measured on the outside. ISO 668 classifies series 1 freight containers by external dimensions. A standard 20-foot container is about 20 feet long, 8 feet wide and 8 feet 6 inches tall outside.
door opening
Door opening is the width and height of the clear opening when a container's doors are open. It is smaller than the container's inside width and height because of the door frame and header. Carrier specs list door opening separately from inside size.
standard container
A standard container is a regular-height dry container, usually 8 feet 6 inches tall outside, as opposed to a high cube. Carrier listings give dry 20-foot and 40-foot specifications at 8 feet 6 inches. Sellers use the word standard with some variation.
high cube container
A high cube container is a container that is taller than standard, usually 9 feet 6 inches tall outside, compared with 8 feet 6 inches for a standard unit. It is often written HC or HQ. The extra height adds inside room.
20 ft container
A 20 ft container is the standard short ISO shipping container. It is about 19 feet 10 1/2 inches long, 8 feet wide and 8 feet 6 inches tall on the outside. It is the most common size in portable storage and counts as one twenty-foot equivalent unit.
ISO 1496
ISO 1496 is a series of international standards for the specification and testing of series 1 freight containers. Part 1 covers general cargo containers for general purposes, including totally enclosed boxes and some vented or open top types. Other parts cover tank, thermal, dry bulk and platform containers.
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