Stowage Factor and Cargo Reference for Dry Bulk Chartering
A practical reference to indicative stowage factors for grain, oilseed meals, fertilizers, coal, ores, cement, salt and other dry bulk cargoes, including an example of when a shipment is deadweight-limited and when it is cubic-limited.
4 min read
By Konstantin Kalnyi, Founder and CEO of Kiev Shipping Ltd
Stowage factor is the volume that one tonne of cargo occupies in the hold, including the space lost between pieces, bags or particles. It is written in cubic metres per tonne (m³/mt) or cubic feet per tonne (ft³/mt) and it is one of the first things a broker asks for, right after the cargo name and quantity.
The values shown are indicative only and must not replace the shipper’s declared cargo information, applicable IMSBC Code requirements, laboratory certificates or vessel-specific calculations.
Actual stowage factors may vary depending on cargo grade, moisture content, origin, compaction, handling method and other shipment-specific conditions.
The reason is practical: it decides whether a fixture is limited by deadweight or by cubic capacity, and therefore which vessel is worth offering at all.
Deadweight or cubic: what actually limits the intake
Every vessel has two separate limits — how much weight she can carry and how much volume her holds hold. Which limit applies depends entirely on the cargo.
Take a geared vessel of about 12,500 dwt with roughly 16,000 m³ (565,000 ft³) of grain capacity, and assume about 500 mt of bunkers, stores and constants:
- Wheat, SF 1.30 — 16,000 ÷ 1.30 ≈ 12,300 mt. Weight and volume run out together: the vessel loads close to full on both.
- Barley, SF 1.55 — 16,000 ÷ 1.55 ≈ 10,300 mt. The holds fill before the marks are reached: about 1,700 mt of deadweight stays unused.
- Potash, SF 0.90 — the holds would take about 17,800 mt, but the vessel can only carry 12,000 mt. She loads down to her marks with the holds roughly two thirds full.
The same cargo quantity therefore needs a different vessel depending on the commodity. This is why an enquiry with the stowage factor stated is checked against the market far faster than one without.
The cargoes we charter, and what they stow at
The table below follows the list of dry bulk cargoes we handle, in the order it appears on our dry bulk cargo page. Figures for the solid bulk cargoes come from the IMSBC Code: each cargo has its own schedule there stating a bulk density and a stowage factor, and that is the reference both the master and the charterer will quote. Grain is not in the IMSBC Code — it is carried under the International Grain Code, and its stowage factor follows from the test weight of the parcel.
The ranges are wide on purpose. A schedule covers every grade of that commodity, so the figure for one specific parcel sits inside a much narrower band — and is confirmed by the shipper before fixing.
| Cargo | m³/mt | ft³/mt | Source and notes |
|---|---|---|---|
| Wheat | 1.25 – 1.35 | 44 – 48 | From test weight, 74 – 80 kg/hl; grain is carried under the Grain Code |
| Corn | 1.30 – 1.45 | 46 – 51 | From test weight; moisture on arrival often disputed |
| Barley | 1.45 – 1.60 | 51 – 56 | From test weight; light grain, frequently cubic-limited |
| Soybeans | 1.28 – 1.40 | 45 – 49 | From test weight; ventilation on long voyages |
| Sunflower meal | 1.39 – 2.09 | 49 – 74 | IMSBC schedule for seed cakes; pellets stow heavier than loose meal |
| Rapeseed meal | 1.39 – 2.09 | 49 – 74 | Same schedule; self-heating risk, ventilation regime agreed in advance |
| Fertilizers | by type | by type | Each type has its own IMSBC schedule — urea, NPK and potash are listed separately below |
| Urea | 1.17 – 1.56 | 41 – 55 | IMSBC schedule; hygroscopic, clean and dry holds |
| NPK | 0.83 – 1.11 | 29 – 39 | IMSBC schedules for ammonium nitrate based fertilizer, non-hazardous and UN 2071; varies with formulation |
| Potash | 0.77 – 1.03 | 27 – 36 | IMSBC schedule; hygroscopic |
| Coal | 0.79 – 1.53 | 28 – 54 | IMSBC schedule; range spans lignite to anthracite, self-heating and methane risks |
| Ores and minerals | 0.29 – 0.80 | 10 – 28 | IMSBC schedule for iron ore; other ores have their own schedules and stow heavier or lighter |
| Cement | 0.67 – 1.00 | 24 – 35 | IMSBC schedule; aerated cement stows far lighter than settled |
| Clinker | 0.61 – 0.84 | 22 – 30 | IMSBC schedule; abrasive, grab discharge usual |
| Gypsum | 0.67 – 0.78 | 24 – 28 | IMSBC schedule; moisture affects weight and flow |
| Salt | 0.81 – 1.12 | 29 – 40 | IMSBC schedule; corrosive to steel, hold protection often agreed |
| Scrap | by type | by type | IMSBC gives "various" — HMS 1 & 2 is normally worked at about 1.4 – 2.2, shredded at 1.2 – 1.5; agreed per parcel |
| Other bulk and dry bulk commodities | by type | by type | Each cargo has its own IMSBC schedule with a stowage factor |
Two entries need a word of explanation. Grain is calculated rather than looked up: test weight is the mass of one hectolitre, and dividing one by the test weight in tonnes per cubic metre gives the stowage factor before broken stowage — wheat at 78 kg/hl gives about 1.28 m³/mt. Scrap has an IMSBC schedule that states "various" for size, density and stowage factor, and that is the honest answer: in the trade HMS 1 & 2 is normally worked at roughly 1.4 – 2.2 m³/mt, shredded scrap stows heavier at about 1.2 – 1.5, and bundles and briquettes heavier still. For scrap the factor is agreed for the specific parcel rather than read off a table.
Bagged, big-bag and breakbulk cargo
For packaged cargo the commodity figure is only the starting point. Bags, pallets and cases leave space that cannot be filled — broken stowage — and the effective factor grows accordingly:
- cargo in 50 kg bags — typically 5 – 10 % above the bulk figure;
- cargo in big bags of 1 – 1.5 mt — typically 10 – 15 % above;
- palletised and cased cargo — 15 – 25 % above, depending on pallet size and hold shape;
- machinery and project units — calculated per unit from dimensions, not from a stowage factor at all.
Hold shape matters here as much as the cargo: a box-shaped hold with wide hatches loses far less space than a hold with sloping tank tops.
What to send with an enquiry
A freight indication is checked against the market faster when the enquiry states:
- cargo name and grade;
- quantity and any tolerance;
- stowage factor, or moisture and grade so it can be estimated;
- packing — in bulk, bags, big bags, palletised;
- loading and discharging ports;
- cargo ready date or laycan;
- loading and discharging terms and rates.
The figures on this page are a working reference for a first check of vessel suitability, not a guarantee of intake. The final quantity depends on the nominated vessel, her hold configuration, the cargo as presented at the loading port and the agreed terms of the voyage.
