Prepared by: Outdoor Materials Hub Technical Content Team · Technical review: 29 July 2026
Heavy outdoor materials create two connected records: a physical packing system that protects and identifies the goods, and a transport data set that carriers, terminals, customs representatives and receiving teams can use. A quotation is not ready for international shipment merely because it shows a product net weight.
This guide explains how ISPM 15, the SOLAS verified gross mass requirement and a traceable packing list fit together for stone, cast products, fencing and long decking profiles. Destination-country rules, carrier instructions, the sales contract and the final packing plan still control the actual shipment.
Three records, three different purposes
| Record | Primary purpose | Key limitation |
|---|---|---|
| Packing specification | Defines protection, unitisation, handling and package identification | Must be designed for the actual product and route |
| Packing list | States what is inside each package and its final dimensions/weights | Generic catalogue values are not final shipment evidence |
| VGM record | Provides the verified gross mass of a packed container before vessel loading | It is a container safety requirement, not a substitute for item-level packing data |
ISPM 15: identify the wood before claiming compliance
The International Plant Protection Convention publishes ISPM 15 for wood packaging material made from raw wood in international trade. The standard covers items such as crates, boxes, packing cases, dunnage and pallets that can carry pest risk. Its public text also lists exemptions for certain low-risk materials, including wood 6 mm or less and processed wood products such as plywood, particle board, oriented strand board and veneer made using glue, heat or pressure.
Do not mark a packing drawing “ISPM 15” simply because the crate supplier says the wood was heated. Confirm:
- which components are raw solid wood and which are processed wood;
- whether the destination applies ISPM 15 and any additional national requirements;
- that regulated wood is treated and marked by an authorised entity;
- that marks remain legible and are not obscured by later packing;
- how repaired or replacement wood will be controlled.
Importer and national plant-protection requirements should be checked before dispatch. A website guide cannot determine whether a particular package will be accepted at a particular border.
SOLAS VGM: the container mass must be verified
The International Maritime Organization explains that SOLAS regulation VI/2 requires the gross mass of a packed container to be verified. The shipper named on the transport document is responsible for providing the VGM, and the VGM is a condition for loading a packed container onto a ship to which the rule applies.
The IMO identifies two methods:
- Method 1: weigh the packed container.
- Method 2: weigh all packages and cargo items, including pallets, dunnage and securing material, then add the container tare mass using a certified method approved by the competent authority where packing was completed.
The responsible shipper and logistics provider should confirm the accepted method, equipment, national tolerance, signature and submission deadline. A supplier’s preliminary packing estimate is not the VGM.
Design package IDs before production is packed
Give every package a unique ID and use that ID on the packing drawing, physical mark, packing list and receiving record. For mixed stone sizes or multiple product families, add item references and quantities to each package rather than listing only total order quantities.
| Package-level field | Recommended content |
|---|---|
| Package ID | Unique crate, pallet, bundle or carton number |
| Contents | Product code, description, size/finish and quantity |
| Dimensions | Final external length × width × height with units |
| Mass | Net goods mass and gross packed mass with units |
| Volume | External packed volume, normally calculated from final dimensions |
| Handling | Fork entry, lifting point, centre-of-gravity or stacking restriction where required |
| Traceability | Order/item/batch references and inspection status |
Use calculations as controls, not as invented facts
For a rectangular package, the basic control calculation is:
Packed volume (m³) = external length (m) × width (m) × height (m).
Total packed volume is the sum of the final package volumes. Package gross mass is the goods plus all packaging, protection and securing assigned to that package. Container Method 2 calculations also include the relevant pallets, dunnage, securing materials and container tare mass under the approved procedure.
These equations help find data-entry errors; they do not authorise estimated values to replace weighing. When final values are unavailable, the commercial record should say “pending final packing” rather than showing an invented zero or a false level of precision.
Match protection to the material failure mode
- Finished stone: separate finished faces, protect edges, control movement and avoid point loading.
- Long WPC profiles: support the length, control bundle distortion and prevent incompatible strapping pressure.
- Cast covers and drainage parts: restrain dense components and protect machined or coated contact surfaces.
- Fencing and pointed metalwork: cap sharp ends, prevent abrasion and define safe lifting.
- Mixed shipments: prevent heavy dense items from transferring load into fragile finishes.
The supplier should issue the proposed packing method for review, then update it after production dimensions and quantity are confirmed.
Separate preliminary freight data from final shipping data
| Status | Permitted use | Label |
|---|---|---|
| Planning estimate | Route and budget comparison | Estimated; subject to final specification and packing |
| Supplier packing proposal | Package and handling review | Proposed; not final packing list |
| Final packing list | Booking, documents and receiving | Final order/package data |
| VGM | Container loading compliance | Verified under accepted method |
The factory, origin point, port, route and container plan may change with the approved product mix. Outdoor Materials Hub does not assume a fixed origin port; these items are confirmed per quotation.
Pre-dispatch technical file
- Approved product and quantity schedule.
- Package design and material specification.
- ISPM 15 control record where regulated wood is used.
- Final package-by-package packing list.
- Package photographs showing IDs and condition.
- Container loading plan and securing record where required.
- VGM record and submission confirmation for applicable sea containers.
- Destination, access, unloading and receiving instructions.
Common export-packing failures
- Product net mass is reused as package gross mass.
- Crate dimensions omit external battens or protection.
- Solid-wood dunnage is added after an ISPM 15 review.
- Package IDs on photographs do not match the packing list.
- A preliminary container estimate is presented as VGM.
- The route is quoted before the actual factory and packed cargo are confirmed.
Read how to prepare a freight quotation, review shipping and delivery planning, or return to the Outdoor Materials Technical Library.
Technical references and limits
- IPPC adopted standards, including ISPM 15
- IPPC ISPM 15 implementation resources
- IMO guidance on verified gross mass of packed containers
Method: this article maps public IPPC and IMO requirements to a buyer-side packing data workflow. It does not certify packaging, determine customs treatment or replace carrier, competent-authority or destination-country instructions.