How a Container House Order Is Loaded: Packing Plan, Weight Limits and Lashing

Freight is the second largest line in a container house order after the units themselves, and almost all of it is decided before the first panel is packed. A loading plan is the document that turns a quotation into a shipment: it tells the factory which items go in which container, tells the forwarder what the weight will be, and tells the buyer what they will be unpacking at destination.

What the plan has to decide

• Unit count per container. Knock-down flat pack ships as panels and corner posts, so volume rather than weight usually limits the count; assembled expandable and capsule units ship closed and are limited by footprint and payload.
• Weight per container. Stay inside the carrier's payload limit, not the container's nominal capacity. A 40HQ has a tare around 3.8 tonnes and a max gross around 30.48 tonnes, so the practical cargo ceiling is roughly 26 tonnes.
• Axle distribution. Load heavy items — steel frames, ballast, tools, spare panels — over and slightly ahead of the trailer axles. Road weighbridges in many countries check axle load, not just total mass.
• Mixed orders. Dormitory modules, an office unit and a sanitary block can share a container only if the packing sequence keeps each unit's parts together, labelled by unit number.

Packing sequence for flat pack modules

1. Floor cassettes first, laid flat and stacked as the base layer.
2. Wall panels on edge, in a rack, in the order they will be erected on site — wall 1 at the door end.
3. Roof cassettes on top, then corner posts and beams bundled and strapped.
4. Fit-out items — doors, windows, sanitary ware, electrical fittings — in labelled cartons inside the wall rack voids, not loose.

Mark every bundle with the unit number and the erection sequence. A container unloaded in the wrong order costs a day of site labour; a container unloaded in the right order costs nothing.

Lashing and dunnage

Documents that travel with the container

• Packing list per container, matching the invoice line by line
• Loading photos: empty container, half loaded, fully braced, door closed with seal number visible
• Verified Gross Mass (VGM) declaration — mandatory under SOLAS for every export container
• Container number and seal number recorded on the bill of lading

Where orders go wrong

The three recurring failures are predictable. First, volume is estimated from the unit footprint rather than from the packed panel stack, so the last two units do not fit and a second container is booked at spot rates. Second, the load is built tall at the door end, which loads the trailer rear axle beyond the legal limit. Third, the packing list is written after loading, from memory, and does not match the invoice — which is exactly the kind of mismatch that stops a letter of credit payment.

The fix is boring and cheap: a packing drawing per container, produced at the quotation stage, confirmed by the buyer, and checked against the loaded container before the doors close.