Wooden Crating for Project Equipment: Structure, ISPM 15 and Packing Process

Wooden crating for project equipment uses load-bearing timber skids, frames and walls and, when needed, vacuum-sealed aluminium foil bags to spread loads, absorb impacts and limit corrosion from moisture and salt air throughout the journey. All natural wood packaging thicker than 6 mm used in international trade must be treated and marked under ISPM 15.

Unlike general cargo that only needs a standard pallet, project cargo such as transformers, CNC lines, turbines or pressure vessels weighs from a few tonnes to hundreds of tonnes, and its centre of gravity is often off-centre. If the base skids are designed with the wrong point loads, the crate can break when lifted at the port; if the wood packaging lacks a valid ISPM 15 mark, the importing country's quarantine authority may require re-treatment, destruction of the wood or re-export of the shipment. This article covers how to choose a crate structure, ISPM 15 requirements and the packing and bracing process for project equipment, from the perspective of H-Cargo.

Wooden crates and cases for project equipment must withstand lifting, protect the equipment and meet ISPM 15 before shipment.

Table of contents:

I. When should project equipment use a wooden skid, an open crate or an enclosed vacuum-sealed case?

II. What is ISPM 15, and how is the IPPC mark on project cargo crates regulated?

III. What are the steps to crate and brace oversized and overweight equipment?

IV. 3 common mistakes when crating project cargo

V. Frequently asked questions (FAQ) about wooden crating for project equipment

VI. Conclusion

I. When should project equipment use a wooden skid, an open crate or an enclosed vacuum-sealed case?

Choosing between a load-bearing Wooden Skid, an Open Crate or an Enclosed Case depends directly on the equipment's sensitivity to salt air, the unit weight and the transport mode.

When planning packing for break bulk vessels, Flat Rack or Open Top containers, you can refer to the export packing guidelines of HPE (Germany), the ASTM D6039 crate standard and the IMO/ILO/UNECE CTU Code (MSC.1/Circ.1497). Protection is usually divided into 3 levels:

• 1. Heavy-duty Wooden Skid / Saddle Base: Only the timber base frame is reinforced, or saddles are cut to fit the equipment body, without surrounding walls. This suits self-supporting, weather-resistant components such as steel tanks, boilers, pipes and heavy steel structures; the main purpose is to spread point loads onto the Flat Rack floor or ship hold and keep the cargo from rolling or sliding.

• 2. Open Wooden Crate: A load-bearing base, a frame and spaced timber slats around the sides, with gaps depending on the design. Suitable for heavy mechanical machinery, dies, valve assemblies and equipment with anti-rust coating that is not very sensitive to moisture but needs a protective frame against knocks during handling.

• 3. Fully Enclosed Case + Vacuum Foil Bag: An internal load-bearing timber frame, closed walls of water-resistant plywood or laminated timber, and inside a vacuum-sealed composite aluminium foil bag with desiccant packs (silica gel, clay desiccant). This option should be prioritized for CNC machines, control cabinets, turbine rotors and electronic equipment on long voyages, especially when stowed on deck or on open Flat Racks and Open Tops.

  
  

Table 1: Selection matrix for wooden skids, crates and cases for project equipment

Technical criteria	Wooden Skid / Saddle	Open Crate	Enclosed Case + Vacuum
Main structure	Longitudinal/transverse timber beams and shaped saddles at the base; machine body exposed.	Load-bearing base + diagonal bracing frame and spaced slat walls on 4 sides.	Load-bearing base + closed walls + vacuum aluminium foil bag & desiccant.
Suitable equipment	Industrial tanks, steel beams, boilers, self-supporting heavy components.	Rough mechanical machinery, moulds, pipeline valve assemblies, metal spare parts.	CNC machines, electrical cabinets, optical equipment, transformers, precision motors.
Salt air protection	Low (add heat-shrink film if the equipment is sensitive to corrosion and goes by sea).	Medium (protects against mechanical impact; needs an internal waterproof cover).	Highest of the 3 options (protection time depends on film quality, amount of desiccant and storage conditions).
Ease of customs inspection	Very fast (labels and serial numbers visible from outside).	Fast (visible through the gaps between slats without removing walls).	Slower; add an inspection window to avoid removing walls or cutting the vacuum bag.

The table is indicative; the specific solution should be based on the equipment's drawings, weight, centre of gravity and the manufacturer's packing recommendations.

Choose a skid, open crate or enclosed case depending on how sensitive the equipment is to moisture and salt air, and on the transport mode.

II. What is ISPM 15, and how is the IPPC mark on project cargo crates regulated?

ISPM 15 (International Standard for Phytosanitary Measures No. 15) is the international phytosanitary standard for wood packaging material in international trade, issued by the International Plant Protection Convention (IPPC – FAO). It applies to natural wood thicker than 6 mm, to limit the spread of pests and insects across borders.

In Vietnam, quarantine of wood packaging material is governed by the Law on Plant Protection and Quarantine 2013 (Law No. 41/2013/QH13) and Circular 33/2014/TT-BNNPTNT (amended and supplemented by Circular 15/2021/TT-BNNPTNT) issued by the Ministry of Agriculture and Rural Development, now the Ministry of Agriculture and Environment. Major markets such as the US, EU, Australia, Japan and China all apply ISPM 15, and each country may have additional requirements. Three core rules shippers need to know:

1. Debarking before treatment: Natural wood used for crates, cases or dunnage must be debarked. ISPM 15 only allows small pieces of bark to remain: less than 3 cm wide (regardless of length), or wider than 3 cm but with each piece under 50 cm² in area.

2. Treatment by an ISPM 15-approved method: For heat treatment (HT), the wood core must reach at least 56°C continuously for at least 30 minutes; the dielectric heating variant (DH) requires 60°C for 1 minute throughout the wood cross-section. HT is the most widely accepted method. For Methyl Bromide (MB) fumigation, wood is fumigated in a sealed chamber for at least 24 hours at the prescribed dosage; the IPPC encourages limiting MB because of its impact on the ozone layer, so check the importing country's requirements before choosing.

3. Correct IPPC marking: The mark consists of the IPPC symbol (wheat ear logo) and the following elements: 2-letter ISO country code (VN) – licensed treatment provider code – treatment method code (HT, DH or MB). The mark must be legible, permanent and placed in a visible position, preferably on at least 2 opposite sides of the crate, and must not be red or orange, as these colours are used for dangerous goods labels.

4. 
   

   

   The ISPM 15 mark should be applied on at least 2 opposite sides; centre of gravity and sling position symbols help ensure correct lifting.

   
   

Table 2: ISPM 15 treatment requirements by type of wood material

Type of packing material for project equipment	Is ISPM 15 treatment & marking mandatory?	Recommended treatment method	Legal & customs notes
Solid natural wood (Solid Wood > 6mm) for base skids, load-bearing frames, crate walls	Mandatory	Usually HT (wood core 56°C / 30 minutes); also check the importing country's specific requirements.	The IPPC mark on the crate is the main basis for quarantine checks; a heat treatment or fumigation certificate is often also required by the buyer or importing country.
Loose timber dunnage and wedges on Flat Racks and in ship holds	Mandatory	HT or MB as required by the importing country.	Dunnage also falls under ISPM 15 and must be treated and carry the IPPC mark.
Industrial plywood, particle board (OSB, MDF) for enclosed case walls	Exempt (if made entirely of processed wood such as plywood, OSB, MDF)	Not needed if the entire crate contains no natural wood members.	Heavy project cargo cases usually have natural wood base skids, so those skids must still be treated and ISPM 15 marked.

III. What are the steps to crate and brace oversized and overweight equipment?

A crating process for project equipment usually has 5 steps, from structural load calculation at the factory to lifting and lashing on the transport unit.

When H-Cargo handles turnkey out-of-gauge cargo transport (OOG), the Project Team advises on crate specifications and coordinates with ISPM 15-certified packing contractors to control the following stages:

1. Step 1 - Survey and crate structure design: Measure the actual dimensions (length x width x height), determine the centre of gravity (CoG) and calculate the cross-section of the base skids (longitudinal & transverse skids) to resist bending during lifting without deflecting the equipment base. Input data should come from the manufacturer's drawings and lifting instructions.

2. Step 2 - Build the load-bearing base and fix the machine feet: Fit hardwood base beams treated to ISPM 15, bolt the equipment feet through the load-bearing beams and fit stoppers in 4 directions (blocking & bracing).

3. Step 3 - Vacuum foil wrapping and moisture protection: Wrap the equipment in a composite aluminium barrier foil bag, pad sharp corners, calculate desiccant quantity per DIN 55474 or an equivalent method, then evacuate the air and heat-seal the bag edges.

4. Step 4 - Build walls, apply the ISPM 15 mark and paint handling symbols: Erect posts, X-shaped diagonal bracing, fit plywood or timber walls and reinforce corners with steel brackets. The outside of the case needs the ISPM 15 mark (preferably on at least 2 opposite sides), the Centre of Gravity symbol and Sling here positions per ISO 780.

5. Step 5 - Lift and lash on the transport unit: Use a spreader bar to lift the crate onto the container or trailer, then lash it according to the lashing and securing standards for project cargo in line with the CTU Code.

   

   Real project equipment crates, from ISPM 15-treated wooden skids to enclosed cases on bearers and oversized crates awaiting lifting at the factory.

Field example: load-bearing wooden skids for two steel tanks on a 40' Flat Rack

In one shipment handled by the H-Cargo Project Team, two large steel tanks were placed on timber, lashed on a 40' Flat Rack container and then loaded onto a low-bed truck at the workshop. For this type of cargo, the packing goal is to support the tank body in the right positions and keep the tanks from rolling or sliding, rather than enclosing them completely.

Instead of building a fully enclosed case (costly in materials and increasing the out-of-gauge dimensions), the suitable solution for this cargo was a load-bearing wooden skid with shaped saddles (saddle skid) made of ISPM 15-treated timber:

• Timber bearers were arranged to transfer the load onto the load-bearing beams of the 40' Flat Rack floor, combined with timber saddles cut to the curve of the tank bottom to prevent rolling.

• The tank and skid assembly was lashed to the Flat Rack floor, then the whole unit was placed on a low-bed trailer for transport from the workshop to the port.

Related articles:
- Destuffing over-height containers at port
- Industrial boiler transport

IV. 3 common mistakes when crating project cargo

• Mistake 1 - Using additional dunnage not treated to ISPM 15: The crate built at the workshop is fully marked, but during lashing at the port a few untreated pieces of scrap wood are used to wedge the crate feet on the Flat Rack. Dunnage also falls under ISPM 15, so even a small amount of non-compliant wood can cause the shipment to be held for treatment, destruction of the wood or re-export.

• Mistake 2 - Missing sling position marks and no top reinforcement: For heavy wooden cases, if port workers place slings away from the load-bearing beams or gather the slings while the top of the case has no compression struts, the slings can crush the roof and walls and damage the equipment inside. Clear sling marks together with a spreader bar help limit this risk.

• Mistake 3 - Crates taller than necessary: Base skids and roofs built a few dozen centimetres too high can push the total height (cargo plus vehicle) over the road limit, forcing the shipper to change the transport plan or pay extra for destuffing over-height containers at the port yard.

  
  

V. Frequently asked questions (FAQ) about wooden crating for project equipment

Below are answers to the 3 questions shippers ask most often about wooden crating and ISPM 15.

1. Does a crate made entirely of plywood have to be fumigated and ISPM 15 marked?

No, if the entire crate structure (including feet, braces and walls) is made of processed wood such as plywood, OSB or MDF. ISPM 15 exempts these materials because they are produced with glue, heat and pressure. However, for heavy project equipment, the load-bearing base skids and frame usually use solid natural wood; in that case the natural wood parts must still be treated and ISPM 15 marked.

2. Does the ISPM 15 mark on project equipment crates expire?

ISPM 15 does not set an expiry for the IPPC mark; a properly treated and marked crate can be reused as long as it has not been repaired or remanufactured. When repaired (replacing or adding wooden pieces), the replacement wood must be treated and marked; if this cannot be met, the whole crate must be re-treated, re-marked and the old marks removed. Remanufactured crates (most components replaced) must be fully re-treated and re-marked.

3. How long does designing, crating and ISPM 15 treatment take for a project machinery shipment?

It depends on dimensions, number of crates, whether the wood is pre-treated, and kiln or fumigation chamber schedules; for a typical shipment, it is usually a few working days from drawing approval. Heat treatment needs enough time for the wood core to reach 56°C for 30 minutes (actual kiln time is longer, depending on wood thickness), MB fumigation needs at least 24 hours, not counting foil wrapping, wall building and documentation. Shippers should include packing in the plan as soon as the vessel schedule is confirmed so it does not run up against the closing time.

VI. Conclusion

Crating project equipment is a structural and quarantine problem at the same time: the crate must withstand lifting, protect the equipment from moisture and salt air, and the wood must comply with ISPM 15. The most cost-effective approach is usually to design packing together with the handling, lashing and transport plan from the start, so that overall dimensions fit the vessel, container and trailer, limiting lost slot charges and destuffing fees at the port. Three things to do before crating:

• Choose the right packing level (skid, crate or case) based on equipment sensitivity, weight and transport mode.

• Use treated natural wood carrying the IPPC mark for every component, including extra dunnage at the port.

• Mark the centre of gravity and sling positions per ISO 780 and control crate height so it does not exceed road limits.

Send equipment drawings, dimensions and weight so the H-Cargo Project team can advise on crate specifications, coordinate with an ISPM 15-certified packer and propose a suitable transport plan.

Author: Navy Ngo - Project team

Contact us for a free consultation:

H-Cargo International Logistics

• 113-115 Ung Van Khiem St., Ward Thanh My Tay, Ho Chi Minh City

• Tel: +84 888 909 186

• Email: project@hcargovn.com

• Web: www.hcargovn.com

Sources cited: ISPM 15 standard of the International Plant Protection Convention (IPPC – FAO); Law on Plant Protection and Quarantine 2013 (Law No. 41/2013/QH13); Circular 33/2014/TT-BNNPTNT and Circular 15/2021/TT-BNNPTNT; IMO/ILO/UNECE CTU Code (MSC.1/Circ.1497); ISO 780 on packaging symbols; ASTM D6039; DIN 55474; the article on out-of-gauge cargo transport on hcargovn.com. Accessed 29/10/2026. For reference only, not a quotation. Check that regulations are in force at the time of application.

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