A contractual clause requiring variations to be in writing and signed by both parties operates as an obligation to co-operate in recording the variation, not as a precondition to the builder's entitlement to payment for variation work actually performed. A mere reference by an arbitrator to evidence in the reasons does not incorporate that evidence into the award for the purpose of identifying manifest error on the face of the award.
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2 of the 16 citing cases carry a classified treatment. How each court treated it is available to signed-in members.