Averaging and Reversing Laytime

A Fixed Laytime Charterparty may allocate a single block of Laytime for both loading and discharging, or it may divide the allowance into distinct periods for each operation. A combined allowance is particularly familiar in tanker chartering, where loading and discharge often proceed under a single overall time regime. In dry bulk and general bulk trades, by contrast, the charterparty frequently sets separate loading and discharging rates because the speed of the two operations may differ materially according to cargo type, shore gear, grabs, pumps, labour availability, berth capacity, and local port practice.

Where the charterparty fixes separate rates, the calculation should normally be prepared separately for loading and separately for discharge, even where the numerical rate happens to be identical. If the charterparty also provides for both Demurrage and Despatch, the result of the loading calculation may produce one financial consequence at the end of loading, while the discharge calculation may produce a second result after completion of discharge. The practical importance is obvious: a ship may save time at the loading port but lose more time at the discharging port, or the reverse may occur.

From the late nineteenth century, charterparties began to include wording designed to prevent a rigid separation between the two operations from producing commercially harsh results. Clauses appeared allowing the time saved in one operation to be applied against excess time used in the other. The historical language was not always precise, and early forms sometimes used the expression “average” in a manner that modern laytime practice would now identify more closely with reversibility.

“Charterers to be at liberty to average the days for loading and discharging in order to avoid Demurrage.”

The old wording therefore needs careful treatment. In its historical setting, the expression could be read as permitting the charterer to treat the loading and discharge allowances as a combined pool. In modern usage, however, a distinction is drawn between averaging and reversing. The distinction is not merely linguistic. It can alter the amount of Demurrage or Despatch payable and may also affect when the charterer must elect how the time allowance is to be applied.

 

 

Modern Meaning of Averaging and Reversing Laytime

The modern approach treats “averaging” and “reversing” as separate concepts. Averaging normally requires the loading and discharge calculations to be made independently, after which time saved in one operation is set off against time exceeded in the other. Reversing, by contrast, gives the charterer an option to combine the loading and discharging allowances into one aggregate allowance. Once that option is exercised, the calculation resembles a total Laytime provision covering both operations.

The practical difference may be substantial. Averaging preserves the character of the two separate calculations before the balance is struck. Reversing creates a single pooled allowance for the voyage. It is also important to remember that reversibility concerns the relationship between loading and discharging allowances. It does not normally permit time to be shifted between multiple loading ports or between multiple discharging ports unless the charterparty clearly provides for that result.

The modern definitions commonly used in laytime practice therefore serve a useful commercial function. They reduce the risk that parties will argue later about whether the charterer merely has a right of set-off between loading and discharge, or a wider right to treat all allowed time as one combined fund. Even so, older charter forms and amended fixtures can still generate uncertainty, particularly where the printed form has been altered by rider clauses or recap wording.

 

 

Illustrative Laytime Calculation

The difference between the two concepts can be seen from a simple example. Assume that the charterparty allows two weather working days for loading and four weather working days for discharging. Assume also that the Demurrage rate is US$18,000 per day and the Despatch rate is US$9,000 per day. If loading saves one day but discharge uses four days beyond the permitted discharge allowance, the result depends on whether the charterparty provides for averaging, reversibility, or neither.

Basis of calculation	Loading result	Discharge result	Financial result
Averaged Laytime	One day saved	Four days exceeded	Net three days Demurrage at US$18,000 per day = US$54,000
Reversible Laytime	Loading and discharging allowances pooled	Total allowance of six days applied across the voyage	Two days Demurrage at US$18,000 per day = US$36,000
No averaging or reversing	One day Despatch payable	Four days Demurrage payable	US$9,000 Despatch set against US$72,000 Demurrage, producing US$63,000 net exposure

 

 

This example illustrates why the precise wording of the charterparty must be checked before any final calculation is issued. A single expression in the Laytime clause may shift the financial outcome by thousands of dollars. In larger bulk trades and tanker fixtures, where Demurrage rates may be far higher and delays may run for many days, the difference between the two methods can become commercially significant.

 

 

Cases on Averaging Laytime

The early authorities on averaging reflect the transition from older commercial wording to the more disciplined modern distinction. In Molière Steamship Co Ltd v. Naylor, Benzon & Co, the court considered a clause giving the charterer liberty to average loading and discharging days. Kennedy J treated the provision as permitting the charterer to add the two allowances together and apply the time used against the aggregate. On modern terminology, that approach is closer to reversibility than averaging. The decision is therefore useful historically, but it must be handled with caution when applying present-day drafting.

The reasoning in Molière Steamship Co Ltd v. Naylor, Benzon & Co rested partly on evidence of how the provision was understood in practice. Because the wording was capable of more than one interpretation, the court was prepared to consider how commercial parties had applied it. Later courts regarded that result as unusual. In Alma Shipping Co SA v. V M Salgaoncar e Irmaos Ltda, Devlin J treated the earlier decision as anomalous and did not regard it as a straightforward construction of the clause in the sense now required by modern analysis.

Oakville Steamship Co Ltd v. Holmes raised another important point: whether the charterer could change position after already taking Despatch at the loading port. Loading was completed quickly, discharge was slow, and the charterer later wished to rely on the averaging provision. Bigham J held that, by requesting and obtaining Despatch Money (DM) at Cartagena and having it endorsed as an advance of freight, the charterer had elected not to average. It was too late to reverse that election after discharge. The case remains important because it shows that rights relating to averaging may be affected by election, payment, and conduct.

The modern foundation of averaging was laid more clearly in Watson Brothers Shipping Co Ltd v. Mysore Manganese Co Ltd. The charterparty covered iron ore from Marmagoa to England and contained a clause providing that days were to be averaged over all voyages performed during the charter. Although only one voyage ultimately took place, the court had to decide whether the charterer could add the discharge allowance to the loading allowance. Hamilton J rejected that argument. The judge treated the loading and discharging allowances as separate. Demurrage incurred at the load port could be reduced by time saved at discharge, but the allowances were not simply merged into one pool.

That approach gives averaging its modern meaning. The loading calculation is first carried out on its own terms. The discharge calculation is then examined separately. Only after the two results are known is a balance struck. Time saved at one end may reduce excess time at the other, but the charterer does not obtain an unrestricted right to combine the two periods unless the wording clearly provides for reversibility or an equivalent aggregated allowance.

Alma Shipping Co SA v. V M Salgaoncar e Irmaos Ltda confirmed this distinction. The charterparty, on the C(ore) 7 form, concerned iron ore from Mormugao to Rotterdam. Loading took more than three weeks, while discharge was completed in just over a day. The parties proposed different calculation methods. The shipowners’ approach would have produced a small Demurrage liability. The charterers’ approach, based on full aggregation, would have produced Despatch. Devlin J preferred the method that treated loading and discharging separately and then struck a balance between time saved and time exceeded.

Devlin J also recognised that, if the matter were entirely new, there might be an argument for treating “averaging”, “adding”, and “reversible” clauses as aiming at broadly similar commercial results. However, the authorities had already drawn a line between a clause using the language of averaging and a clause using wording that clearly adds or reverses the allowed periods. That distinction remains central to careful Laytime analysis.

 

Cases on Reversing Laytime

The leading early authority on reversibility is Love and Stewart Ltd v. Rowtor Steamship Co Ltd, a House of Lords decision arising from a charter for pit props. The cargo was to be loaded and discharged at a stated daily rate, with the days “reversible”. The effect was that time saved at the loading port increased the time available for discharge. The House of Lords treated the expression as enabling the receiver to use at discharge the time not consumed in loading. In commercial terms, reversibility allowed the charterer to move unused time from one end of the voyage to the other.

Verren v. Anglo-Dutch Brick Co (1927) Ltd also concerned reversible working days, this time in the context of a small coaster carrying bricks from Belgium to the River Thames. The Court of Appeal emphasised that reversibility applies within the voyage covered by the charter. It does not automatically allow time saved under one charter to be transferred freely to another unless the relevant chartering documents expressly provide for that result. Scrutton LJ’s comments are often remembered for their criticism of the word “reversible”, but the practical meaning was accepted: days may be used for either loading or discharging.

Z Steamship Co Ltd v. Amtorg, New York considered the relationship between reversibility and Despatch. Goddard J accepted that the charterer could say, once loading was completed, that days had been saved. The difficulty lay in whether saved time could be paid for as Despatch and still used again at the discharge port. Later authority doubted any approach that would allow the same saved time to operate twice. The better modern view is that payment of Despatch at the loading port exhausts the financial consequences of the time saved; it should not then be reused to reduce discharge Demurrage or increase discharge Despatch.

The Vancouver strike cases provided a practical framework for applying Reversible Laytime. Where loading and discharging time are reversible, the first step is to identify the number of days of the quality specified by the charterparty that are allowed for each operation. Those days form a pool. If fewer days than allowed are used at loading, the unused balance is carried forward to discharge. If loading exceeds the loading allowance, the excess is drawn from the discharge allowance. The final discharge calculation then determines whether Demurrage or Despatch is due.

This approach is especially important where the charterparty measures Laytime in weather working days or similar qualified days. What is carried forward is not simply clock time but a number of days of the contractual quality. If a half weather working day is saved at a load port where the working day is eight hours, it must be translated appropriately when applied at a discharge port where the working day may be twenty-four hours. The same logic applies to interruptions caused by weather, holidays, or other excepted periods.

The Atlantic Sun dealt with whether a reversing clause operates automatically or gives the charterer an option. Mocatta J concluded that, on the wording before the court, the charterers did have an option. The relevant charterparty contained a clause for Despatch at each end and a separate provision stating that Laytime allowed for loading and discharging was to be reversible. The judge considered that the word “reversible” conferred a choice upon the charterer, supported by the structure of the Despatch and Demurrage clause. The case is a reminder that the presence of reversibility does not always mean the same thing in every charterparty; the surrounding wording remains critical.

 

Clauses Similar to Averaging and Reversing Laytime

Not every charterparty uses the labels “average” or “reversible”. Some clauses state the intended result more directly, for example by providing that days not consumed in loading may be added to the discharge time, while extra time consumed in loading may be deducted from the discharge time. In Rederi Aktiebolaget Transatlantic v. La Compagnie Française des Phosphates de L’Océanie, the Court of Appeal considered such a clause in a charter for phosphate cargo carried from Makatea to Sweden.

The issue was whether extra time used at the loading port should be measured as running Demurrage days or as weather working days, because Laytime itself was expressed in weather working days of twenty-four consecutive hours. The Court of Appeal held that like must be compared with like. If weather working days are the contractual currency, the number carried forward or deducted must also be weather working days. A saved or exceeded day cannot be converted into a different quality of day unless the charterparty clearly requires it.

This principle is commercially sensible. A shipowner and charterer agree a particular type of Laytime because that type reflects the operational assumptions of the trade. If the clause allows time to move from one operation to another, the transferred time must retain the same contractual character. Otherwise the calculation may distort the bargain by allowing a party to gain the benefit of days that would never have counted in the first place.

 

 

Multiple Charters and Part Cargoes

Modern shipping operations frequently involve more than one charter or contract of carriage applying to the same ship during the same voyage. This is particularly common in parcel tanker trades, but it also occurs in dry cargo operations where a ship carries several part cargoes for different charterers or receivers. A charterparty may expressly state that the cargo is only a part cargo and that the shipowner has liberty to complete the ship with other cargoes. Such wording is often described as a liberty to complete clause.

An early example is the Centrocon completion clause, which permits owners to complete the ship with other merchandise from port or ports to port or ports, provided that the additional cargo does not hinder the loading or discharging of the charterer’s cargo. Modern parcel tanker forms are more detailed. They may deal expressly with segregation, commingling, loading and discharge rotation, and the shipowner’s right to carry other cargoes for other charterers, whether or not the additional cargoes are on the same route.

The reason these clauses matter is that Laytime and Demurrage are normally contractual obligations owed under each separate charter. When several cargoes are carried at once, the same physical delay may affect more than one contract. The question then becomes whether each charter is to be applied independently, whether the charters are to be read together, or whether the wording requires a shared calculation of time and Demurrage.

 

Are Concurrent Charters to Be Read Together?

Occasionally, the same ship may be under two charterparties between the same parties at the same time. The fact that the parties and ship are the same does not automatically mean the two charters merge into one contract. The decisive question is whether the documents, read objectively, show that the parties intended the charters to operate together or separately. The cases show that cross-references, amendments, identical commercial terms, and the sequence of negotiation may all be relevant.

In Sarma Navigation SA v. Sidermar SpA (The Sea Pioneer), the owners first fixed the ship for a part cargo of steel bars. The right to load a completion cargo was initially excluded. Three days later, the same parties concluded a second charter for steel coils to be loaded at another port and discharged at another discharge port, although both parcels were ultimately discharged at the same port. Because the second charter referred to the first and the first charter was amended to allow further cargo, the Court of Appeal held that the two charters should be read together. Laytime was therefore calculated on a consecutive or cumulative basis rather than producing overlapping Demurrage claims for the same discharge period.

The result was different in Transamerican Steamship Corporation v. Tradax Export SA (The Oriental Envoy). There, the two contracts were made before the particular ship had even been nominated, and it was not within the contemplation of the parties at the time of either fixture that the same ship would necessarily perform both. The Demurrage rates were different and the Laytime provisions were not the same. Parker J held that there was no basis for reading the two charters together. Each charter retained its separate contractual identity.

The Mexico I raised a related but slightly different issue. The question was not simply whether one contract or two existed, but whether the later agreement displaced the original Laytime machinery and substituted a composite arrangement for both cargoes. The Court of Appeal held that it did not. Although the two contracts contained substantially similar provisions, they were not knitted together by express cross-references or amendments in the way seen in The Sea Pioneer. The parties might have avoided the dispute by drafting a unified Laytime scheme, but the court could not create one for them after the event.

These authorities show that the answer is one of construction. A court or tribunal will look for clear contractual indications that the parties intended one combined regime. Without such indications, the safer starting point is that each charter stands on its own, even where the same ship and the same commercial adventure are involved.

 

Commencement and Running of Laytime Under Multiple Charters

In a multiple charter situation, the ordinary rules governing Notice of Readiness (NOR), arrived ship status, readiness, and commencement of Laytime continue to apply to each charter. If both charters are port charters and both cargoes are to be discharged at the same port, the ship may be able to tender Notice of Readiness (NOR) under both charters upon arrival within the port. However, at a discharge port, this will normally require that the cargo under each charter is freely accessible.

Overstowage is the main complication. If one cargo is stowed beneath another cargo, the ship cannot usually be treated as ready to discharge the over-stowed cargo until access has been obtained. In Government of Ceylon v. Société Franco-Tunisienne d’Armement-Tunis (The Massalia (No 2)), part of a flour cargo was over-stowed by general cargo carried under a separate contract. Diplock J held that Laytime for the flour cargo did not begin until all of the flour was accessible. The principle is straightforward: the ship must be ready for the particular cargo operation required by the charterparty.

Where both cargoes are accessible, Laytime under both charters may run concurrently after valid Notice of Readiness (NOR) and the relevant waiting period. If both cargoes are discharged at the same berth, time may continue to run under each charter until the cargo carried under that charter has been discharged. If cargo operations for one charterer must be suspended so that cargo under another charter can be worked, the suspended time will not normally count against the charterer whose cargo is not being handled, unless the charterparty expressly allocates the risk differently.

If one or both charters are berth charters, time under that charter will not usually begin until the ship is at the specified berth or a berth within the contractual description and, in the case of discharge, the relevant cargo is accessible. Some clauses, however, alter this result by making time lost waiting for berth count as Laytime or by deeming the ship ready despite being out of berth. Such clauses must be read carefully in a multiple cargo context.

 

Time Lost Waiting for Berth

Clause 4 of the GENCON form is a familiar example of a provision stating that time lost waiting for berth counts as Laytime. The clause is particularly important when congestion prevents the ship from reaching a berth where cargo operations can take place. The clause can operate before a valid Notice of Readiness (NOR) could otherwise be given, because its commercial purpose is to allocate to the charterer the risk of berth congestion.

The harder question is whether the clause applies where the cargo under the charter is over-stowed by other cargo. If the ship cannot yet discharge the relevant cargo because another cargo blocks access, can time nevertheless be said to be lost waiting for that berth? The cases do not all speak with one voice, and the answer may depend heavily on whether the ship was truly waiting for the berth required for that cargo or whether the operative cause of delay was the need to remove other cargo first.

In The Massalia, the ship had a part cargo of flour, some of which was over-stowed by general cargo. On arrival at Colombo, congestion required the ship to wait at anchorage before a berth became available. Diplock J held that, although Laytime for the flour cargo could not begin until all flour was accessible, the shipowners could still rely on the time lost clause for the period spent waiting for berth. Time counted from arrival, stopped when the ship shifted to berth, and then resumed once the flour became accessible.

Agios Stylianos produced a different result. The ship was carrying vehicles and cement under separate charters, with the cement wholly over-stowed by the vehicles. The ship waited fourteen days at Lagos before berthing. The owners recovered Demurrage from the vehicle charterers for the waiting time but failed in a similar claim against the cement charterers. Donaldson J distinguished The Massalia and held that the ship had not been waiting for the cement berth during the period when the vehicles still had to be discharged. In that analysis, the cement charterers’ obligation to nominate or use a berth arose only after the cement became accessible.

The Tropwave indicated a more generous approach to the shipowner, suggesting that, where all charterparties were in the same form, owners might at least prima facie claim Demurrage in respect of all cargoes even though one cargo was over-stowed. London arbitration decisions have also tended to focus on causation. If the ship would have had to wait the same period for the relevant berth even if the cargo had been accessible, congestion may be treated as the operative cause and the time lost clause may apply. If the delay was really caused by over-stowage and the need to discharge other cargo first, the claim is much weaker.

The most coherent approach is therefore causal. The decision-maker should ask what actually prevented the cargo operation. Was the ship delayed by congestion at the berth where the relevant cargo was to be discharged, or by the fact that the cargo was inaccessible? If congestion was the real cause, the time lost clause is more likely to bite. If the cargo could not have been discharged even with an available berth, the argument for counting the waiting time is much less persuasive.

This uncertainty matters commercially because it is often impossible at the time of fixing to predict exactly how part cargoes will be stowed, which berth will become available first, or whether all cargoes will be discharged at one berth or several. Parties who want a definite allocation of risk should therefore draft expressly. They may state, for example, whether time lost waiting for berth counts even when the relevant cargo is over-stowed, or whether such time counts only after the cargo becomes physically accessible.

 

Cargo Operations While Waiting for Another Berth

Another recurring issue is whether time continues to run against one charterer while the ship is waiting for that charterer’s berth but is simultaneously loading or discharging cargo for another charterer. Before The Stolt Spur, it was generally accepted that, where one berth was unavailable, time could continue to run against the charterer whose berth was unavailable while the ship worked other cargo, unless the charterer could show that the ship’s other activity actually prevented the charterer from using the ship.

The Stolt Spur introduced a more restrictive analysis. The ship arrived at the discharge port and tendered Notice of Readiness (NOR) for a cargo occupying only a few of more than forty cargo tanks. The berth required by the charterers was occupied and remained unavailable for more than two weeks. During that period, the ship discharged one cargo and loaded another for different charterers. The tribunal held that Laytime and Demurrage did not run during the periods when the ship was occupied with those other operations, and Andrew Smith J upheld that conclusion.

The decision rested on the view that the shipowner must have the ship ready and available for the charterer’s cargo operations in order to claim Demurrage. If the ship is unavailable because the shipowner is using the ship to perform other contracts, that unavailability may itself be treated as preventing cargo operations. The conclusion remains controversial because earlier authorities suggested that time should only stop where the charterer is actually impeded from using the ship. The practical lesson is that owners who operate in parcel or multiple-charter trades should not assume that time will always continue to run while the ship performs other cargo operations.

 

Demurrage Under Multiple Charters

Where a ship is employed under multiple charters, each charter may contain its own Demurrage Rate. If the contractual conditions for Demurrage are satisfied under more than one charter, the shipowner may in principle claim under each charter. Charterers have often argued that such claims amount to double recovery or a windfall, but English law has generally treated the matter as one of contract. If the parties agreed separate Demurrage regimes for separate cargoes, the court will not easily rewrite those bargains.

In The Tropwave, Parker J rejected the argument that overlapping Demurrage necessarily produced double damages. Demurrage is often described as liquidated damages for detention, but there is no absolute external measure that fixes what the owner’s loss must be in every case. A shipowner carrying three part cargoes might agree a lower Demurrage rate under each charter than would have been agreed for a full cargo. Conversely, the total of the rates may reflect the commercial value of the entire employment. The mere existence of overlapping claims does not invalidate the agreed provisions.

The Oriental Envoy developed the same point. Where the nominated carrying ship is not known at the time of fixing, the Demurrage rate may be set by reference to the cargo rather than the size of the ship. If the owner later nominates a larger ship and carries additional cargo, the aggregate Demurrage may still represent a legitimate contractual allocation of delay risk. Parker J also described Demurrage as a simple contractual obligation: if the charterer fails to complete within the stipulated Laytime, the agreed sum becomes payable according to the charterparty terms.

London Arbitration 26/89 similarly accepted that full Demurrage could be claimed for each parcel unless the parties had agreed a single calculation. The Mexico I recognised that multiple Demurrage under parallel contracts has long been known to the law, although a court or tribunal might in an appropriate case prevent true double recovery for exactly the same loss if the contractual structure allowed such an approach. The starting point remains freedom of contract: separate charters produce separate rights unless the parties have linked them.

 

Carriage of Edible Vegetable Oils

The edible vegetable oil trade presents a particularly sophisticated example of multiple cargo operations. Parcel tankers may carry dozens of different parcels under separate charterparties or booking arrangements. Cargoes may be loaded or discharged from shore tanks, barges, feeder ships, road tankers, or rail tank cars. Ports such as Rotterdam, Hamburg, and major Southeast Asian loading centres often handle complex sequences of commingled and segregated parcels. The operational reality is therefore very different from a conventional single-cargo voyage.

The Tanker Voyage Charter Party known as Vegoilvoy is widely used in this trade, although other forms may also be encountered. Vegoilvoy contains provisions addressing Notice of Readiness (NOR), commencement of Laytime, allowed running hours, Demurrage, concurrent cargo operations, and the allocation of time among multiple shipments. These clauses are intended to reflect the parcel tanker business, but their drafting has generated disputes because the commercial situations are highly variable.

 

Nomination of Loading and Discharging Berths

In many conventional voyage charters, the charterer nominates the berth or at least controls the berth selection within the contractual range. In vegetable oil parcel trades, the position is often different. The shipowner may choose the berth or terminal rotation, while shippers and receivers are invited to bring or take cargo at the berth selected for the ship. This reflects the owner’s need to coordinate many parcels, tanks, and terminals efficiently across the voyage.

The result is that charterers may have limited direct control over where the ship berths, yet still contribute to time lost before the ship reaches the berth. In practice, the time between commencement of Laytime and connection of the first cargo hose may be apportioned across all cargoes loaded or discharged at the relevant terminal. This allocation reflects the shared benefit and burden of using the ship as a parcel carrier rather than a dedicated full-cargo ship.

 

Commencement of Laytime and Waiting Time Under Vegoilvoy

Clause 4 of Vegoilvoy provides a detailed scheme for Notice of Readiness (NOR) and commencement of Laytime. Once the ship has arrived at the loading or discharge port and is ready, Notice of Readiness (NOR) may be tendered by the master or agent. The ship may be treated as ready whether she is in berth or out of berth, whether arrival is inside or outside business hours, and whether ballast water or slops remain in tanks, subject to the terms of the clause.

Laytime commonly begins after the expiry of six running hours from tender of Notice of Readiness (NOR), whether the ship is in berth or out of berth, or immediately on arrival in berth if that occurs first. The clause also excludes delay in reaching the berth if the delay is caused by the fault of the ship or owner. Another part of the clause provides that Laytime begins when the ship arrives at the loading or discharge port whether or not a berth is available, provided Notice of Readiness (NOR) is tendered as required.

This wording is designed to prevent berth congestion from leaving the shipowner uncompensated, while still preserving the requirement that Notice of Readiness (NOR) be properly tendered. It also reflects the fact that parcel tanker trades may involve a queue of cargo interests sharing the same ship. Waiting time is often allocated among cargoes, not because each charterer controls the berth, but because each charterer participates in the commercial use of the ship at that terminal.

 

Laytime and Demurrage in Vegetable Oil Parcel Trades

Vegoilvoy clauses dealing with Laytime and Demurrage distinguish between ordinary operations and situations involving commingled or separate shipments loaded or discharged concurrently at the same installation. Clause 5(a) provides a running-hour allowance for loading, discharging, and used Laytime. Delays caused by breakdown or inability of the ship’s facilities to load or discharge within the allowed time do not count. Night restrictions imposed by the owner may also stop time, while night restrictions imposed by the charterer, shipper, consignee, or port authority usually count as used Laytime.

Clause 5(b) deals with commingled or separate shipments loaded or discharged concurrently at the same installation. It provides that the Laytime allowed to each shipper is the gross number of hours allowed for any of the commingled or separate shipments, and it creates a conclusive presumption that loading or discharging of all such shipments commenced simultaneously. Clause 11 then sets out the Demurrage consequences, including apportionment among shipments in proportion to their share of the total, unless the delay is caused by a specific charterer or shipper, in which case the whole Demurrage may be charged to that party.

These provisions have been considered in London and New York arbitrations. The key problem is the word “concurrent”. If it meant that every parcel must begin and end at exactly the same moment, the clause would rarely apply in real parcel tanker operations. Different parcels are often handled through different hoses, tanks, barges, or shore lines; they may overlap substantially without being perfectly simultaneous. A commercially sensible interpretation treats the clause as applying where the cargo operations are coordinated and overlapping, rather than wholly independent and consecutive.

The New York reasoning is particularly useful in explaining the commercial logic. Parcel tanker operations seldom begin simultaneously except by coincidence. The presumption of simultaneous commencement should therefore be understood as a calculation device. If the parcels could have begun together, and no ship or shore restriction requires a different approach, Laytime is first calculated as though they did begin together. If Demurrage results, it is then allocated according to the apportionment clause. Where a party creates a restriction that forces consecutive handling, liability may fall on the party responsible for that restriction.

From these authorities and the wording of the Vegoilvoy clauses, several practical conclusions follow. Clauses 5(a) and 11(a) should be read together, and clauses 5(b) and 11(b) should also be read together. The first pair applies most naturally to full cargoes and ordinary separate calculations. The second pair applies where commingled or separate parcels are worked concurrently at the same installation. In part cargo cases, the facts determine which pair governs the calculation.

If clauses 5(a) and 11(a) apply, the quantity of cargo carried for the particular charterer determines the Laytime allowed. Waiting time between the effective Notice of Readiness (NOR) and connection of the first loading or discharge hoses is commonly apportioned among the relevant charterers according to their cargo proportions at that installation. Once the ship is alongside, delay in connecting hoses for one charterer while other cargoes are being worked may not count against that charterer if the delay is caused by the terminal’s inability to handle all parcels at once.

If cargo operations on a particular charterer’s cargo are suspended because the ship chooses to work another charterer’s cargo, time will normally not count against the charterer whose operations have stopped. If the interruption arises from a port authority restriction affecting the charterer’s own cargo operation, time is more likely to continue. The essential question is whose cargo or whose operational restriction caused the delay. Only a complete cessation of operations on the particular charterer’s cargo will usually stop time as against that charterer.

Under clauses 5(a) and 11(a), Laytime or Demurrage ends when the hoses relating to the particular charterer’s cargo are disconnected. Under clauses 5(b) and 11(b), the relevant endpoint is the final disconnection of hoses for the last parcel at the installation, because the calculation treats the concurrent operation as a shared event. If clauses 5(b) and 11(b) apply, the benchmark shipment is the shipment that produces the greatest Laytime allowance after quantity and loading or discharge rate are considered. The time used is then compared with that benchmark allowance, and any Demurrage is apportioned among the cargoes in the agreed ratio.

The party asserting that the concurrent operation rules apply should be prepared to prove the facts supporting that assertion. Evidence may include terminal records, hose connection and disconnection times, tank plans, cargo sequence, pumping logs, barge or shore tank availability, and communications showing whether the operations could have been performed concurrently. Without such evidence, a tribunal may default to ordinary separate calculations under clauses 5(a) and 11(a).

 

Squeegeeing and Sweeping

Vegetable oil cargoes raise special cleaning and recovery issues. Crude palm oil may be solid at ambient temperatures, leaving residues that must be scraped or swept from the ship’s tanks. Refined palm oils are generally liquid at ambient temperatures but may still require mopping or squeegeeing to recover remaining cargo and clean the tanks. These operations are commercially important because vegetable oils can be valuable and even small residues may represent significant cargo value.

Clause 7(e) of Vegoilvoy provides that squeegeeing is to be paid by the shipowner and that the time used is not to count as used Laytime. Although the clause refers expressly to squeegeeing rather than sweeping, the same commercial reasoning applies to both. Both operations are directed toward recovering residue and preparing the tanks, and both are closely connected with the physical characteristics of the cargo. Unless the charterparty clearly draws a distinction, sweeping and squeegeeing should normally be treated alike for Laytime purposes.

 

Transhipment in Vegetable Oil Trades

Transhipment is another common feature of the vegetable oil trade. A mother ship may load parcels in Malaysia, Indonesia, or other producing regions for carriage toward Europe. At recognised transhipment ports such as Rotterdam, Hamburg, or Mediterranean hubs, individual parcels may be transferred into smaller daughter ships for final delivery to the ultimate discharge port. This structure allows owners and traders to combine long-haul economies of scale with flexible distribution to smaller ports.

The usual commercial practice is that the time spent transhipping the cargo does not count against discharge Laytime. However, the discharge Laytime and Demurrage calculation may still be based on the events at the ultimate discharge port. The question is whether the mother ship charterparty’s Laytime and Demurrage provisions continue to govern discharge from the daughter ship after transhipment.

The Christos provides the leading illustration. The owners agreed to carry palm oil from Belawan to Tuapse, with an option to tranship the cargo on a single ship to the discharge port. The cargo was ultimately discharged at Novorossisk from a daughter ship after transhipment at Piraeus. The charterers argued that the Demurrage provisions applied only to the named mother ship and fell away once transhipment occurred. Mance J rejected that analysis. The discharge Laytime and Demurrage provisions in the mother ship charter continued to apply between the parties in relation to discharge from the daughter ship.

That result is commercially practical. A transhipment option would lose much of its utility if the agreed Laytime and Demurrage machinery disappeared as soon as the cargo moved to a daughter ship. Unless the charterparty clearly provides otherwise, the better view is that the agreed discharge regime follows the cargo to the ultimate discharge operation contemplated by the charter. The identity of the physical ship used for final delivery does not, by itself, eliminate the contractual allocation of time and delay risk.

Practical Drafting and Laytime Calculation Lessons

The authorities on averaging, reversing, multiple charters, and parcel tanker operations all point to the same practical conclusion: Laytime disputes are often created by small differences in wording. A clause that says “average” should not automatically be treated as a clause that says “reversible”. A clause that allows unused loading time to be added to discharge time must be applied using days of the same contractual quality. A clause that links multiple cargoes must state clearly whether the calculation is shared, separate, concurrent, or cumulative.

For shipowners, the main risk is assuming that a ship carrying several part cargoes can always generate several simultaneous Demurrage claims. That may be correct if the charters are independent, but it may be displaced by cross-references, combined Laytime wording, concurrent operation clauses, or evidence that the ship was unavailable for a particular charterer’s cargo operations. Owners should preserve detailed records showing when each cargo was accessible, when each berth was available, when hoses were connected and disconnected, and why any interruption occurred.

For charterers, the main risk is assuming that part cargo status protects them from waiting time or overlapping Demurrage. If the charterparty makes time lost waiting for berth count, or if the charterer agrees to a parcel tanker form with shared waiting time provisions, the charterer may be liable for a portion of delay even without direct control over berth selection. Charterers should therefore review the entire Laytime scheme before fixing, not just the headline rate and Demurrage figure.

For brokers and operators, the safest course is to use precise recap wording. If Laytime is to be averaged, say so and specify the method. If Laytime is to be reversible, state whether the charterer has an option and when that option must be exercised. If multiple part cargoes are contemplated, specify whether Laytime and Demurrage are calculated separately per charter, shared by cargo quantity, or governed by a benchmark shipment. If over-stowage may occur, state whether time lost waiting for berth counts before the relevant cargo becomes accessible.

In technical maritime work, the calculation should always follow the contract. Commercial fairness may explain why a clause was drafted, but it cannot replace the wording chosen by the parties. The strongest Laytime analysis therefore combines close reading of the charterparty, accurate operational chronology, and disciplined application of the legal authorities. Where those elements are present, even complex multiple-charter and parcel tanker disputes can be reduced to a clear and defensible calculation.

 

Detailed Professional Commentary on the Laytime Framework

The legal and commercial discussion of Averaging, Reversing, multiple charters, and vegetable oil parcel trades should not be treated as a collection of isolated rules. Each topic is part of the wider structure of voyage charter risk allocation. Voyage chartering is built around the idea that the shipowner provides the ship for a particular maritime adventure, while the charterer bears the contractual responsibility for cargo operations within the agreed time. Laytime provisions define the period of permitted delay. Demurrage then applies when that permitted period is exceeded. Despatch, where agreed, rewards the charterer for finishing earlier than the allowed time.

Because Laytime is a contractual allowance rather than a general measure of fairness, small differences in wording can alter the result. A clause allowing time to be averaged does not necessarily produce the same calculation as a clause making time reversible. A clause referring to “time lost waiting for berth” may operate before Laytime would otherwise commence. A clause dealing with part cargoes may produce separate calculations for each cargo or a shared calculation across cargoes. These distinctions are technical, but they are not artificial. They determine who pays for real commercial delay.

In practice, Laytime disputes often arise because the parties agree a fixture quickly and assume that standard expressions will work in the same way in every trade. That assumption is unsafe. The meaning of the same expression may differ according to the printed form, the rider clauses, the recap wording, the type of cargo, the number of ports, the berth arrangements, and the surrounding commercial structure. A careful operator therefore reads the Laytime clause together with the Notice of Readiness (NOR) clause, berth clause, exceptions, strike provisions, completion clause, and any special wording dealing with part cargoes or concurrent cargo operations.

 

Why Separate Loading and Discharging Allowances Matter

Separate loading and discharging allowances are common where the practical operation at one end of the voyage is expected to differ from the other. A cargo may be loaded by shore conveyor and discharged by grabs. A cargo may be loaded from a terminal with high loading capacity and discharged at a smaller port with limited labour. A tanker cargo may be pumped ashore under one regime and loaded under another. The charterparty therefore often reflects two different operational assumptions. Combining those assumptions without clear wording may distort the bargain.

If the loading allowance is exhausted but discharge later saves time, an averaging clause may permit a credit. If discharge is delayed but loading saved time, the same clause may reduce the discharge Demurrage. However, the clause does not usually erase the historical fact that one operation exceeded its own allowance. It merely permits the saved time from the other operation to be brought into account. This is why averaging must begin with two separate calculations. The balance is struck only after each operation has first been measured on its own contractual basis.

Reversibility works differently because it converts separate allowances into a combined resource. The charterer may treat unused loading time as additional discharge time or, depending on the facts, draw on discharge time to absorb an excess at loading. The commercial effect is more flexible. It may also be more favourable to the charterer, especially where delays are concentrated at one end of the voyage. For that reason, shipowners and charterers should not assume that a clause using the word “average” is enough to create a fully reversible allowance.

 

Election, Payment, and the Timing of the Charterer’s Choice

A recurring practical issue is when the charterer must decide whether to rely on averaging or reversing. Some clauses expressly state when the election must be made, but many do not. Where the charterer receives Despatch at the loading port, the payment may be treated as an election not to preserve the saved time for later use. This was the commercial logic in Oakville Steamship Co Ltd v. Holmes. Once the charterer has taken the financial benefit of saved time, it is difficult to argue that the same saved time should later be used to reduce discharge Demurrage.

The same principle applies even more strongly where the parties have settled the loading account and recorded the settlement on the bill of lading or freight account. A settlement made at one stage of the voyage may have consequences for later Laytime rights. Operators should therefore avoid premature agreement on Despatch if there is any possibility that the saved time will be needed against discharge delay. If the charterer wants to preserve the point, the settlement should be expressly made without prejudice to the final voyage Laytime calculation.

For shipowners, the issue is equally important. If the owner pays Despatch at the loading port without reservation, the owner may later face an argument that the payment resolved all consequences of the saved loading time. If the charterparty permits reversible Laytime and the owner expects the final account to be settled only after discharge, the owner should avoid partial settlements that create ambiguity. The best practice is to state in the fixture or in the operational correspondence whether Despatch and Demurrage will be settled at each end or only upon completion of discharge.

 

The Role of Contractual Quality of Days

A Laytime day is not always an ordinary calendar day. It may be a weather working day, a working day, a running day, a day of twenty-four consecutive hours, or a day subject to Sundays, holidays, strikes, or other exceptions. When time is transferred, averaged, or reversed, the contractual quality of the day must be preserved. A saved weather working day cannot simply be treated as a running day unless the contract says so. This principle is fundamental because the parties have chosen the type of day as part of the price and risk allocation.

The issue becomes particularly important when loading and discharging ports have different working practices. A loading port may operate only during daylight or normal working hours, while a discharge port may work continuously. If the charterparty speaks in weather working days, the calculation must translate the saved or exceeded portion into the corresponding contractual unit. It is not enough to compare clock hours mechanically. The question is how much of the agreed contractual allowance has been consumed or preserved.

Fractions of a day should be handled with equal care. If a half weather working day is saved at loading, it may translate into a different number of clock hours at discharge depending on the working regime. The calculation should record both the contractual fraction and the clock-time effect. This is particularly useful where the final Demurrage or Despatch amount is calculated in running days after Laytime has expired or would have expired.

 

Averaging and Reversing in Operational Documentation

A reliable Laytime calculation depends on the Statement of Facts, port logs, Notice of Readiness (NOR), berth records, weather stoppage records, hose connection and disconnection times, cargo completion times, and correspondence between agents, masters, terminals, charterers, and shipowners. Where averaging or reversing is involved, the calculation should make clear which periods belong to loading and which belong to discharge. The account should then show how saved time or excess time has been transferred or offset.

A common error is to show only the final net result without explaining the method. This may conceal whether the calculation was performed as averaging or reversing. In a dispute, the absence of method can be as damaging as an arithmetic mistake. A professional Laytime statement should therefore include a short note identifying the contractual basis: “Separate calculations prepared and time saved at loading set off against excess discharge time under averaging clause,” or “Loading and discharging allowances combined pursuant to reversible Laytime clause.”

Where there is no averaging or reversing provision, the calculation should resist the temptation to balance the two operations merely because the result appears fair. If loading produces Despatch and discharge produces Demurrage, the charterparty may require both results to stand. Conversely, if the parties intended a net voyage calculation, that intention should appear in the charterparty. The calculation must follow the bargain, not the calculator’s view of commercial symmetry.

 

A Closer Reading of the Averaging Authorities

The historical cases on averaging demonstrate how commercial usage and legal construction gradually separated. Molière Steamship Co Ltd v. Naylor, Benzon & Co is significant because it shows that the old market expression “average” was once used more loosely. The court accepted a construction that effectively pooled the loading and discharge allowances. Modern readers should not extract from that case a general rule that averaging means aggregation. The later authorities refined the language and made the present distinction sharper.

Watson Brothers Shipping Co Ltd v. Mysore Manganese Co Ltd is important because it asks what the word “average” means in the context of stipulated days for shipment and stipulated days for discharge. Hamilton J’s answer was that the right to Demurrage at the loading port must first be determined by the events at the loading port and the number of days allowed there. Subsequent discharge events may then reduce the amount payable, but they do not rewrite the loading calculation from the beginning.

Alma Shipping Co SA v. V M Salgaoncar e Irmaos Ltda confirmed the same discipline. The case is valuable because Devlin J examined alternative computation methods. The shipowners’ method, the charterers’ aggregation method, and the balancing method all had different commercial consequences. The court’s choice of the balancing method gives practical content to averaging: separate calculations are made, then the credit is applied. The decision also warns against treating “average”, “add”, and “reversible” as interchangeable terms.

 

A Closer Reading of the Reversibility Authorities

The cases on reversibility demonstrate the broader effect of pooling. In Love and Stewart Ltd v. Rowtor Steamship Co Ltd, the saved loading time enlarged the discharge time. The calculation did not merely produce a credit after the event; it changed the time available for discharge. That is the essence of reversibility. It allows the charterer to move the unused portion of one allowance into the other operation.

Verren v. Anglo-Dutch Brick Co (1927) Ltd confirms that reversibility should not be extended beyond its commercial setting. The fact that the parties used reversible days for a voyage did not mean that days could be interchanged across a series of voyages or charters without clear wording. This matters today in contracts of affreightment, consecutive voyages, and multi-parcel programs. If the parties intend cross-voyage credits, the charterparty should state the mechanism expressly.

The Atlantic Sun adds another important dimension: the charterer may have an option, depending on the wording. The word “reversible” may not automatically reverse the time unless the charterer elects to use it. This matters where reversing would produce a better result for the charterer in some cases but not in others. A well-drafted clause should specify whether reversibility is automatic, optional, and, if optional, when and how the option must be exercised.

 

Multiple Charters: Commercial Structure and Legal Identity

Multiple charter arrangements are commercially attractive because they allow the shipowner to optimise space and route economics. A ship may have capacity for more cargo than a single charterer requires. By carrying completion cargoes, the owner can improve earnings, reduce ballast legs, and serve several cargo interests on one voyage. Charterers may also benefit by securing transport for smaller parcels that would not justify fixing an entire ship.

However, the legal structure must match the operational structure. If each charter is independent, each charterer may have separate Laytime and Demurrage obligations. If the charters are linked, a shared calculation may apply. If the cargoes are worked concurrently, a special apportionment provision may govern. If the cargoes are worked consecutively because of stowage or terminal limitations, time may stop for one charterer while another charterer’s cargo is handled. The commercial efficiency of part cargo carriage therefore brings legal complexity.

The distinction between reading charters separately and reading them together is especially important when the same parties are involved. The Sea Pioneer shows that express cross-references and amendments can tie two charters together. The Oriental Envoy shows that similarity of commercial setting is not enough. The Mexico I shows that even substantially identical provisions may not create a composite Laytime regime unless the contracts are clearly connected. The safest drafting approach is to state expressly whether the charters are independent or to be read as one arrangement for Laytime purposes.

 

Over-stowage and Cargo Accessibility

Over-stowage creates one of the most difficult problems in multiple cargo voyages. A ship may be physically at the port and capable of discharging some cargo, but not yet capable of discharging the cargo under the particular charter. Readiness is cargo-specific. The ship must be ready to perform the operation required by the charterer. If the cargo is buried beneath other cargo, the ship is not ready for that charterer’s discharge, even though the ship is ready and working for another cargo interest.

The Massalia (No 2) captures this point clearly. The ship could discharge accessible flour and general cargo, but not all of the flour cargo. Laytime for the flour cargo did not begin until the flour was fully accessible. The same principle applies in modern dry bulk, breakbulk, project cargo, and parcel cargo operations. A Notice of Readiness (NOR) tendered for an inaccessible cargo may be ineffective unless the charterparty contains a clause deeming readiness or otherwise transferring the risk.

The practical consequence is that stowage planning can affect Laytime rights. If a shipowner agrees to carry completion cargo and over-stows one charterer’s cargo, the Shipowner may delay the commencement of Laytime for that charterer. If the charterparty permits overstowage or contains a liberty to complete, the owner may still need to show that the arrangement did not hinder loading or discharge of the charterer’s cargo beyond what the contract allowed. Cargo accessibility should therefore be recorded in the stowage plan, mate’s receipts, and discharge sequence.

 

Time Lost Waiting for Berth: Causation as the Organising Principle

The time lost waiting for berth cases are difficult because they sit at the intersection of berth congestion, cargo readiness, and multiple-charter operations. A time lost clause is designed to protect the shipowner from berth congestion. It is not necessarily designed to protect the owner from the consequences of stowing another cargo above the charterer’s cargo. The key question is therefore causal: what caused the lost time?

If the ship would have waited the same period for the relevant berth even if the cargo had been accessible, the argument for counting the time is strong. The delay is caused by congestion, which is the risk the clause addresses. If, however, the ship could not have used the relevant berth because the cargo was inaccessible and another cargo had to be discharged first, the delay is not truly time lost waiting for that charterer’s berth. The operative cause is the cargo arrangement.

This causal approach also helps reconcile the competing authorities. The Massalia can be understood as a case where congestion was treated as the real reason why the ship could not proceed to berth. Agios Stylianos can be understood as a case where the cement cargo was not yet in a position to use a berth because the vehicles had to be discharged first. London arbitration decisions have tended to apply a similar practical test, asking whether the relevant cargo would have been delayed by congestion in any event.

The Darrah supports the same reasoning by describing time lost waiting for berth as the period during which the ship would have been in berth and at the charterer’s disposition if congestion had not prevented access to the berth. The phrase “would have been” forces a counterfactual inquiry. One must ask what would have happened without the congestion. If the answer is that the cargo still could not have been discharged because it was over-stowed, the clause may not assist the owner for that period.

 

Concurrent Cargo Operations and Availability of the Ship

Where a ship is waiting for one charterer’s berth but uses the waiting period to work another cargo, a second causal issue arises. Is the ship still available to the first charterer? If the berth is not available in any event, the owner may argue that the other cargo operation causes no loss to the charterer. The charterer may respond that Laytime or Demurrage should not run because the ship was not actually at the charterer’s disposition during that period.

The Stolt Spur gives force to the charterer’s argument. If the ship is occupied loading or discharging another cargo, the ship may be unavailable for the charterer’s operation. The unavailability can itself be treated as a reason why cargo operations did not proceed. This reasoning places a heavier evidential burden on owners in parcel trades. Owners may need to show not only that the charterer’s berth was unavailable, but also that the other operations did not in fact deprive the charterer of any opportunity to work the cargo.

The practical answer is documentation. If the berth required by the charterer was occupied throughout the period when other cargo operations took place, that fact should be recorded. If the charterer could not have worked the cargo even if the ship had been idle, the owner’s position is stronger. If the berth became available while the ship was still working another cargo, the owner’s position is weaker. Timing evidence may decide the dispute.

 

Demurrage as Contractual Risk Allocation

The multiple Demurrage cases show that Demurrage should not be treated too simplistically as a single measure of physical detention of the whole ship. In part cargo trades, a Demurrage rate may reflect the cargo quantity, the freight, the expected duration of the operation, the market level, and the bargaining power of the parties. It may not correspond neatly to the daily earning capacity of the entire ship. This is why courts have been reluctant to treat overlapping Demurrage claims as automatically impermissible.

At the same time, the possibility of multiple Demurrage claims creates commercial sensitivity. A charterer carrying a small parcel may be surprised to face Demurrage while the ship is also earning freight or Demurrage under other contracts. The legal answer is that the charterer agreed to a contractual regime for its own cargo. The commercial answer is that charterers should negotiate apportionment clauses if they want shared liability rather than independent Demurrage exposure.

For shipowners, separate Demurrage rights should not encourage careless drafting. If the shipowner wants independent Demurrage under each charter, the charterparty should avoid wording that suggests a single shared calculation. If the owner agrees to concurrent operation clauses, benchmark shipment provisions, or proportional apportionment, those provisions may replace the ordinary right to claim the full rate from each charterer. The financial model of the fixture should match the legal wording.

 

Vegetable Oil Parcel Trades: Why the Rules Are Different

Vegetable oil parcel trades differ from ordinary bulk trades because the ship may carry many liquid parcels with different physical properties, tank compatibility requirements, heating requirements, cleaning requirements, and discharge destinations. Cargoes may be commingled if compatible and agreed, or segregated where quality or ownership requires separation. Some parcels may be discharged to shore tanks, while others are delivered into barges or smaller feeder ships. The ship’s operation is therefore a coordinated logistics exercise rather than a simple single-cargo discharge.

The Vegoilvoy form attempts to reflect this reality by deeming readiness in certain circumstances, allowing Laytime to begin out of berth, and providing apportionment mechanisms for concurrent shipments. These clauses recognise that no single charterer may control the whole operation, but each charterer benefits from the ship’s participation in the shared parcel program. The form therefore spreads certain waiting and Demurrage consequences across cargo interests.

The difficulty is that real operations do not always fit neatly into the categories of full cargo, commingled cargo, separate concurrent shipments, or consecutive shipments. A parcel may begin later because a shore tank is not ready. Another parcel may stop because barges are unavailable. A third parcel may be delayed by heating or quality inspection. The calculation must identify whether the delay belongs to the whole installation, a particular cargo, a particular ship facility, or a particular shore restriction.

Applying Clauses 5(a), 5(b), 11(a), and 11(b)

The first step in applying the Vegoilvoy Laytime and Demurrage provisions is to identify the operational pattern at the installation. If a single charterer’s cargo is loaded or discharged in an ordinary way, clauses 5(a) and 11(a) will usually apply. If several shipments are worked as a coordinated concurrent operation at the same installation, clauses 5(b) and 11(b) may apply. The distinction is factual and must be supported by records.

When clauses 5(a) and 11(a) apply, the calculation is made by reference to the particular charterer’s cargo quantity and the allowance specified in Part I. The calculation should include the waiting period from commencement of Laytime to the first hose connection according to the applicable custom or clause, but it should stop time when the charterer’s cargo is not being worked because the ship is voluntarily handling another charterer’s cargo. It should resume when work on the charterer’s cargo resumes.

When clauses 5(b) and 11(b) apply, the calculation moves from an individual cargo model to a shared operation model. The benchmark shipment is identified by comparing the Laytime allowance generated by each shipment. The benchmark is not necessarily the largest tonnage if discharge rates differ. It is the shipment that produces the longest contractual allowance. The total time used at the installation is then compared with that benchmark allowance, and the resulting Demurrage is apportioned among the shipments as the clause requires.

This method avoids both extremes. It prevents the owner from recovering full overlapping Demurrage from every charterer for a single coordinated operation, but it also prevents charterers from escaping liability merely because their own parcel was not the last to finish. The parties have agreed that the concurrent operation should be treated as a shared event. The calculation should honour that agreement.

 

Evidence Required in Parcel Tanker Laytime Disputes

A parcel tanker Laytime dispute is evidence-heavy. The calculation may require the charterparty, recap, tank plan, cargo manifest, load and discharge sequences, terminal pumping logs, shore tank readiness records, barge nomination records, hose connection and disconnection statements, heating logs, sampling and analysis records, weather records, and port authority restrictions. Without these documents, it may be impossible to determine whether a delay belongs to the ship, a charterer, the terminal, a receiver, or the shared operation.

The Statement of Facts (SOF) should therefore be more detailed than in a simple single-cargo voyage. It should identify each cargo parcel, the installation at which it was handled, the time its hoses were connected and disconnected, interruptions affecting that parcel, and whether other parcels were worked during the interruption. It should also record whether cargoes were capable of being handled concurrently or whether physical limitations forced a consecutive sequence.

When disputes arise, a tribunal will usually prefer contemporaneous operational records over later explanations. A later assertion that operations “could have been concurrent” may carry little weight if the terminal log shows that only one shore line was available. Similarly, a claim that delay was caused by the charterer may fail if the ship’s own heating or pumping system was not ready. Good records are not administrative formality; they are the foundation of the legal calculation.

 

Squeegeeing, Sweeping, and Tank Cleaning as Laytime Issues

Squeegeeing and sweeping may appear minor compared with berth congestion or prolonged discharge delays, but in vegetable oil trades they can become financially important. Residue recovery can take hours. If the ship is on Demurrage, even a short period may have a significant cost. The charterparty must therefore define whether the time counts and who pays for the work.

The commercial reason for excluding squeegeeing time from used Laytime is that the operation is closely connected with the ship’s tanks and the owner’s obligation to deliver the cargo properly and prepare the tanks. The charterer receives the benefit of maximum cargo recovery, but the work is not necessarily part of ordinary discharge by the receiver. The clause therefore allocates both cost and time to the shipowner.

The same reasoning supports treating sweeping in the same manner where crude palm oil or similar cargo leaves semi-solid residues. The physical technique differs, but the commercial purpose is comparable. Unless the wording makes a deliberate distinction, a narrow reading that excludes sweeping may produce an artificial result inconsistent with the cargo’s characteristics.

 

Transhipment and Continuity of the Laytime Regime

Transhipment raises a different type of problem because the named mother ship may no longer be the ship physically performing final discharge. The charterer may argue that Demurrage provisions apply only to the named ship. The owner may argue that the charterparty contemplated transhipment and that the Laytime and Demurrage regime must therefore continue to apply to the ultimate discharge operation. The Christos supports the owner’s position where the charterparty gives a transhipment option and the final discharge is part of the contemplated carriage.

Commercially, this makes sense. If the owner has the contractual right to tranship, the charterparty must continue to provide machinery for final discharge. Otherwise the parties would be left with uncertainty or an implied duty of reasonable diligence instead of the agreed Laytime and Demurrage bargain. The better view is that the cargo’s arrival and discharge at the ultimate port remain governed by the charterparty unless the parties expressly agree a different regime after transhipment.

Operators should nevertheless draft transhipment clauses carefully. The clause should state whether Laytime at the ultimate discharge port is calculated by reference to the mother ship charter, whether time spent in transhipment counts, whether the daughter ship must tender Notice of Readiness (NOR), and whether Demurrage accrues at the same rate. Without such wording, the parties may have to rely on implication and authority, which increases dispute risk.

 

Practical Checklist for Laytime Calculators

A professional Laytime calculator handling these issues should first identify the form and all rider clauses. Standard printed wording may have been amended by recap terms, side letters, or special clauses. The calculator should then determine whether loading and discharge allowances are separate, averaged, reversible, or combined. If averaged or reversible, the calculation should expressly state which method is being used and why.

The next step is to confirm the quality of the allowed time. Weather working days, running days, working days, and holidays all require different treatment. The calculator should avoid mixing clock time and contractual time without explanation. If fractions of days are carried from one port to another, the basis for conversion should be shown.

In a multiple charter situation, the calculator should identify whether the charters are independent or linked. This requires checking cross-references, amendments, common addenda, identical or different Demurrage rates, and whether the same ship was contemplated when each fixture was made. If the documents are independent, separate calculations will usually be required. If the documents are linked, a cumulative or shared calculation may be necessary.

For over-stowed cargo, the calculator should identify when the relevant cargo became accessible. Notice of Readiness (NOR) may be invalid before that time unless the charterparty changes the ordinary rule. If a time lost waiting for berth clause is relied upon, the calculator should identify the operative cause of the delay and ask whether the ship would have been at the berth for the relevant cargo but for congestion.

For parcel tanker operations, the calculator should identify each installation and each parcel. The calculation should record whether cargoes were full, separate, commingled, concurrent, or consecutive. If concurrent operation clauses apply, the benchmark shipment should be identified and the Demurrage apportioned according to the clause. If ordinary clauses apply, time should be counted or stopped by reference to the particular charterer’s cargo operation.

 

Drafting Recommendations for Shipowners and Charterers

Shipowners should draft completion clauses that expressly preserve the right to carry other cargoes without losing Laytime and Demurrage rights, but the clause should also address whether other cargo operations can interrupt time under the charter. If the owner expects time to continue while other cargo is worked and the charterer’s berth is unavailable, the charterparty should say so clearly. Reliance on general law may be uncertain after The Stolt Spur.

Charterers should require clarity where their cargo may be over-stowed. A clause may state that Laytime does not commence until the cargo is accessible, that time lost waiting for berth does not count until accessibility is achieved, or that any delay caused by other cargo operations is excluded. If the charterer accepts a liberty to complete clause, the charterer should ensure that the liberty is limited by an obligation not to hinder the loading or discharge of the charterer’s cargo.

Both parties should address the settlement of Despatch and Demurrage. If the account is to be settled at each end, the charterparty should say whether payment at the loading port prevents saved time from being used at discharge. If the account is to be settled only after completion of discharge, the charterparty should prevent interim payments from being treated as final elections. Clear settlement language can avoid disputes after the ship has sailed.

Where Vegoilvoy or another parcel tanker form is used, the parties should consider whether the printed clauses fit the actual trade. If a fixture involves known consecutive operations, the parties may need to modify the concurrent shipment wording. If a terminal has limited lines or barges, the charterparty should allocate delay caused by those limitations. If transhipment is likely, the clause should state the Laytime consequences expressly.

 

Commercial Importance of Accurate Laytime Analysis

Laytime and Demurrage are not merely administrative matters. They affect freight economics, voyage profitability, charterer exposure, and claims strategy. A ship delayed for several days at a high Demurrage rate may turn a profitable fixture into a loss. A charterer exposed to unexpected overlapping Demurrage may face a cost not built into the cargo sale. Shipbrokers and Ship Operators therefore treat Laytime wording as a financial term, not simply a legal formality.

In volatile markets, the importance increases. When freight rates are high and ship availability is tight, Demurrage rates may also rise. Delays caused by congestion, strikes, weather, or terminal restrictions can become more expensive. In parcel trades, the number of parties involved multiplies the potential for disagreement. The same operational event may be viewed differently by the owner, charterer, shipper, receiver, terminal, and broker.

Accurate analysis also protects commercial relationships. A well-prepared calculation that explains the contractual basis, identifies the relevant facts, and applies the authorities transparently is more likely to be accepted or settled. A calculation that simply asserts a large Demurrage figure without method is more likely to be challenged. In this field, clarity can reduce both legal cost and operational friction.

 

Conclusion

Laytime Averaging, Laytime Reversing, multiple charters, time lost waiting for berth are all specialised parts of the same broader subject: the contractual control of time in voyage chartering. The shipowner’s right to be paid for delay and the charterer’s right to use the agreed Laytime depend on the exact words of the charterparty and the operational facts recorded during the voyage.

Laytime Averaging requires separate calculations followed by a set-off. Laytime Reversing allows the allowed time to be pooled, usually at the charterer’s option if the wording supports that interpretation. Multiple charters may be separate or linked, depending on the documents. Over-stowed cargo raises questions of readiness and accessibility. Time lost waiting for berth depends heavily on causation. Parcel tanker forms such as Vegoilvoy create specialised rules for shared operations, concurrent shipments, squeegeeing, sweeping, and transhipment.

The best protection against dispute is precise drafting supported by disciplined documentation. The charterparty should state the intended method, and the Statement of Facts (SOF) should record the events needed to apply it. Where that is done, even a complex voyage involving several cargoes, several charterers, different berths, and multiple Laytime regimes can be analysed with confidence. Where it is not done, the parties may find that a few words in a Laytime clause determine a substantial commercial claim.