Container door dimensions

Shipping container door dimensions by type

Two boxes of the same type differ a little: on the six shipping lines’ sheets we compared, a 20 ft door is 2,340 to 2,350 mm wide and 2,274 to 2,292 mm high, a 40 ft high cube door 2,577 to 2,597 mm high, and a 40 ft high cube reefer door 2,471 to 2,569 mm high. Several lines give their figures as examples, not as a promise for each box. For a load with little room to spare, ask for the data sheet of the box you will get; a used box comes without one, so measure its door yourself, at the narrowest point between the frames and under the header. Flat racks have no doors.

What is the standard door size of a shipping container?

About 2,340 × 2,280 mm, or 234 × 228 cm, on a standard box, whatever its length; the width, 2,340 mm, is the same on every dry box, high cube included. Some guides give 2,286 × 2,261 mm instead: those are the smallest door openings the ISO standards allow on a box 8 ft 6 in high, not the size of a typical door.

Container door height: 20 ft, 40 ft and high cube

• 20 ft and 40 ft standard: 2,280 mm (7′ 6″), against 2,393 mm inside.
• 20 ft and 40 ft high cube: 2,585 mm (8′ 6″), against 2,698 mm inside: 305 mm more than a standard door.
• Reefer: 2,252 mm on a 20 ft and 2,557 mm on a 40 ft high cube, since the insulation takes room all round. Here the sheets give a lower inside height than the door, 2,180 and 2,450 mm, and the load must stay below the red line near the roof that lets the cold air return to the unit: the red line, not the door, sets the limit (reefer container).
• 45 ft: the same door as a 40 ft high cube, 2,340 × 2,585 mm: see the 45 ft container.

40 HC container door height

2,585 mm, or 8′ 6″, on the median of the data sheets, and 2,577 to 2,597 mm from one shipping line to another; the door is 2,340 mm wide. The box itself stands 2,896 mm (9′ 6″) high outside, against 2,591 mm for a standard one: 40 HC container dimensions gives the rest.

Why the door is lower than the inside

On a dry box, above the door runs the rear header, the steel beam that joins the two corner posts at the top of the door end, and it hangs below the roof: on the data sheets, the door is 113 mm lower than the inside height on a standard box and 113 mm lower on a high cube. A load that fits under the roof may not pass the door. Measure it on its pallet, add the height the forklift lifts it off the floor, and keep some room to spare. Forklifts built to work inside containers, sold as “container specification”, have a low mast and overhead guard; ask the seller of the forklift what height its mast needs.

What if the load does not pass the door?

• Taller than a standard door: a high cube adds 305 mm.
• Taller than any door, or loaded by crane: an open top container, whose door header swings aside and whose roof opens.
• Wider than the box: a flat rack, with no side walls.
• Long and loaded by forklift from the side: an open side container.

A car passes the door of a standard box with room to spare in width; can a car fit in a 20 ft container gives the details.

How a container door works

A container has two door leaves at one end. On a maker’s specification we read, each leaf hangs on four hinges and carries two locking bars: vertical steel rods that turn with a handle, with a cam at each end that turns into a keeper on the frame, at the top and the bottom. Rubber gaskets, of EPDM with a double lip, seal the leaves against the frame and against each other. Fully open, each leaf swings round about 270° to lie against the side wall.

The right-hand leaf opens first and closes last, since it overlaps the left one at the top: customs rules for sealed transport require that order. The customs seal goes through the cam at the foot of the inner locking bar of the right-hand door, and the handles take a padlock; some boxes also have a welded lock box that covers the padlock.

How do you open a container door?

1. Remove the padlock or the seal from the right-hand door.
2. Lift the two handles of that door out of their keepers and turn them to free the cams.
3. Pull the right-hand door open, then do the same with the left-hand one; swing both back against the sides if you need the full opening.

A door that is hard to open is often a sign of a box standing out of level, which twists the frame: set it on level supports, as site preparation and unloading explains.

Markings on the container doors

• Container number and size-type code: at the top right of the right-hand door, in the usual layout.
• Tare weight: painted on the door, usually with the maximum gross weight and the payload.
• CSC safety approval plate: usually on the left-hand door, though the convention only asks for a readily visible place.

Before you buy, check that the number on the door matches the one on the invoice, and read the CSC plate: how to inspect a used container says what it tells you.

Do 40 ft containers have doors on both ends?

A standard 40 ft container has doors at one end only. A double door, or tunnel, container has doors at both ends, so that goods go in at one end and out at the other; its doors are about 2,340 × 2,280 mm on a 40 ft. An open side container adds doors along one long side. Both are on container sizes.

How to fit a door in a shipping container

A door for people, cut into a side or end wall, turns the box into an office, a shop or a home, but it changes its structure:

• Do not cut the frame. Singapore’s Building and Construction Authority, in a 2023 circular on container structures, forbids notching or cutting the top and bottom rails, the corner fittings and the corner posts, and limits openings to half the length of a wall, framed in steel: about 2.9 m in the side of a 20 ft box. Ask the fabricator for a welded steel frame round the opening.
• The CSC plate stops being valid. Under the International Convention for Safe Containers, a box modified in its structure loses its approval until it is recertified, after new tests if required; India’s classification society also asks for recertification. The box can still stand on the ground as a room, but not travel as a shipping container.

A box with a door for people becomes a room, which your local body may need to approve: see permission to place a container, and the container office and container shop pages for such conversions.

Checking the doors of a used container

Open and close both leaves: they should swing freely all the way round and close without forcing. Check that each locking bar engages its keepers at the top and the bottom, that no hinge is broken or seized, and that the gaskets are whole and soft rather than torn or flattened. Then stand inside with the doors shut, in daylight: any light at the edges shows where the rain will come in.