Redwing Construction Ltd v Charles Wishart [2010] EWHC 3366 (TCC)

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 (1) Where a previous adjudicator has decided an issue outside his jurisdiction, it does not preclude a subsequent adjudicator deciding upon the same point at a later date. (2) Where an adjudicator in a contractual adjudication makes an obvious mistake which is merely clerical or arithmetical in nature then he may be able to make use of an implied term that permits him to correct the mistake provided that he does so within a reasonable time of handing down his decision.

Technology and Construction Court, Mr Justice Akenhead


Redwing Construction Limited (“Redwing”) was employed as a contractor by Mr Wishart to refurbish a domestic property in London, under the standard JCT Prime Cost Building Contract form (2006 Revision 1 with amendments) which provided for adjudication.  Under the contract, Redwing were entitled to be paid (1) the Prime Cost, (2) the Contract Fee and (3) and direct loss and/or expense ascertained under the terms of the contract.  The Contract Particulars identified the Contract Fee as £3,500 per week.  The “Estimate Prime Cost” was £723k including £98k for the Contract Fee.  Possession of the site was to be 14th July 2008 and the Date for Completion was 12th December 2008, subject to the usual extension of time provisions.  Variations were ordered, and a short extension of time was awarded.  However, Practical Completion was not achieved until approximately 7 months after the Date for Completion as extended. 

Redwing had submitted applications for extensions of time, which were disputed.  Redwing referred the dispute to an adjudicator (the “first adjudicator”).  Redwing argued that they were entitled to a further extension of time and payment of the weekly Contract Fee throughout the period of the extension.  Mr Wishart argued that the Contract Fee was fixed at £77k, and covered the original contract period of 22 weeks only; any additional amount would be recovered by way of a loss and expense claim, which had not been referred to the adjudicator.  The first adjudicator asked the parties to make submissions with regards to whether the contract allowed for the Contract Fee rate of £3,500 to be adjusted in line with the increased Prime Cost.  Mr Wishart alleged that this issue fell outside the first adjudicator’s jurisdiction, having not been raised by either party.  Redwing did not respond.  In this decision, the first adjudicator extended the Date for Completion by around 3 months and awarded Redwing the Contract Fee at the rate of £3,500 up to that date.  In reaching this decision he held that there was an implied term that the weekly Contract Fee would be payable throughout the period of any extension of time granted.  Importantly, his decision also said that the parties had not intended that the Contract Fee rate should be adjusted in line with increases in the Prime Cost as well as being paid during any period of extension of time.  On receipt of the decision, Redwing wrote to the first adjudicator alleging that this latter finding was not part of the reference to the first adjudicator and therefore should not have been decided upon.   

A further dispute arose following the assessment of the Final Account and was referred to a second adjudicator (the “second adjudicator”).  The dispute included the issue of whether the Contract Fee could be increased in line with the increase in the Prime Cost.  Mr Wishart argued that this point had been decided by the first adjudicator’s decision; Redwing argued that the first adjudicator had not had the authority to make such a decision.  The second adjudicator found in favour of Redwing and applying a mathematical formula, increased the weekly rate to £3,858 per week to reflect a corresponding increase in the Prime Cost.  Subsequently, Redwing pointed out that in calculating the increase in the Contract Fee the second adjudicator had used as the basis of his calculation of the increase in the Prime Cost the “Estimated Prime Cost”, which had included the original Contract Fee.  Redwing suggested that this was an “arithmetical error” which could be amended under the slip rule.  Mr Wishart argued that “Estimated Prime Cost” was the figure stated in the Contract and that this was not something that could be amended under the slip rule.  Despite further exchanges of correspondence, the second adjudicator agreed with Redwing and issued an amended decision two days after issuing his original decision.  This resulted in a greater amount being due by Mr Wishart to Redwing.  Mr Wishart declined to pay any adjustment of the Contract Fee.  Redwing subsequently issued proceedings for the enforcement of the outstanding sum.


The Court addressed the following issues:

  • Whether the dispute decided in the second adjudication had been effectively decided in the first adjudication.
  • Whether the second adjudicator’s correction or amendment to his decision went beyond the proper application of the slip rule.


The Court held:

  • The dispute referred to the first adjudicator did not include the issue as to whether Redwing was entitled to an adjustment of the Contract Fee rate.  Nothing in the submissions of the parties gave the adjudicator jurisdiction over such an issue. 
  • The first adjudicator’s decision that the parties had not intended that the Contract Fee should be adjusted in line with increases in Prime Cost was in any event not a necessary part of his decision.  In effect the disputed paragraph in the first adjudicator’s decision would be classed as if it was an obiter statement made by a judge in court i.e. it did not form part of the rationale of his decision.
  • The second adjudicator did therefore have jurisdiction to rule on this issue and his decision on the point was enforceable.
  • The second adjudicator was not having second thoughts about his decision, nor was he correcting his reasoning, when he issued his revised decision.  In fact, he was merely applying the slip rule, an implied term allowing him to correct a patent error within a reasonable time.  The error was a very obvious arithmetical error.
  • The revision of the second adjudicator’s decision, within 2 days of the original decision, was made within a reasonable time allowing for exchanges of views about the possible revision, and therefore the revision was enforceable.

This summary was provided by CMS Cameron McKenna LLP.

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