Sea container types: dimensions, capacities and the FCL/LCL decision

Sea containers are built to ISO 668, which is why the same box fits every crane, chassis and vessel cell in the world. External dimensions are standardised; internal dimensions and maximum payload vary somewhat with the manufacturer, the age of the unit and the shipping line. The values below are industry averages intended for planning; for critical loads, request the line's own equipment specification.

For exports from Turkey the most common equipment is the 20'DC and the 40'HC. Choosing the right container means weighing volume, weight, palletisation and the road weight limits in the destination country together.

Standard and special container types

DC (dry container) is for general dry cargo. HC (high cube) is approx. 30 cm taller than a standard box and is preferred for bulky but light cargo. Reefer (refrigerated) containers can typically be set between approx. −25 °C and +25 °C; their internal volume is smaller because of the cooling unit and the T-floor. Open tops take tall machinery loaded by crane from above; flat racks carry project cargo that exceeds container dimensions; tank containers carry bulk liquids and gases.

FCL or LCL?

FCL (Full Container Load) means the whole container is allocated to one shipper and freight is a flat rate per box. LCL (Less than Container Load) means a consolidator combines cargo from several shippers in one container and charges on volume (m³) or weight (tonnes), whichever is greater (W/M).

• Volume: as a rule of thumb, above roughly 13–15 m³ a 20'DC FCL starts to cost less than LCL. The break-even point depends on the trade lane and on the origin and destination handling charges applied to LCL.
• Transit time: LCL usually adds several days for consolidation at the origin CFS and deconsolidation at destination.
• Damage and security: an FCL box is sealed by the shipper; LCL cargo is handled several times and travels alongside other shippers' goods.
• Flexibility: LCL suits small, regular lots and lower inventory; FCL suits bulk and heavy shipments.

CBM calculation and real-world capacity

CBM (cubic metre) is length × width × height of a package in metres. Total volume is the sum of each package type's volume multiplied by its quantity. Example: 12 pallets of 120 × 80 × 150 cm: 1.2 × 0.8 × 1.5 = 1.44 m³; 12 × 1.44 = 17.28 m³.

In LCL this shipment is compared with its gross weight in tonnes (say 6 t) and charged on 17.28 W/M. In FCL the nominal volume can mislead: a 33 m³ 20'DC takes only 10–11 Euro pallets (120 × 80 cm) or 9–10 standard pallets (120 × 100 cm) in a single layer; a 40'DC/HC takes roughly 23–25 Euro pallets or 20–21 standard pallets. Weight must be checked separately: a 20'DC is rated for approx. 28 t, but road weight limits in many countries (approx. 40–44 t for tractor, chassis and container combined) keep the practical payload around 20–24 t.

Compare total cost, not just ocean freight: with LCL, origin and destination CFS charges, documentation fees and local delivery are added per m³ and can overtake FCL at medium volumes.

Common pitfalls

Limit Trans settles equipment choice, VGM submission and free-time terms at quotation stage, with the aim of avoiding unexpected demurrage and detention at destination.

• VGM (SOLAS): since 2016 the Verified Gross Mass of every packed container must be submitted to the line before loading. VGM is obtained either by weighing the packed container (Method 1) or by adding cargo, packing and tare (Method 2); in Turkey Method 2 requires authorisation. A container without VGM is not loaded.
• Free time, demurrage and detention: the line grants a number of free days at the port and in the shipper's or consignee's hands. Exceeding the free days at the terminal triggers demurrage; keeping the box outside the port (for stuffing or unpacking) beyond free time triggers detention. Daily rates escalate in tiers.
• Container inspection: before stuffing, check floor, walls, door seals, odour and light ingress (holes). Damage not recorded on the Equipment Interchange Receipt (EIR) at pick-up may be charged to the shipper.
• Cargo securing: use chocks, airbags and lashing to prevent shifting, and distribute weight evenly along the box. The IMO/ILO/UNECE CTU Code is the international reference.
• Seal and document consistency: the seal number must match on the bill of lading, the export declaration and the VGM submission.