CA 3 November 1987. The plaintiffs were subcontractors to the defendants under a contract for construction of a road . The subcontract being in the standard form issued by the Federation of Civil Engineering Contractors for use in conjunction with the ICE Conditions of Contract CL15 . The plaintiffs works were delay ed and the defendant sought to set off a claim for damages flowing from a delay against an interim payment which would otherwise have been due. The plaintiff claimed that the defendant had failed to give the required contractual notice in time and that any claim for delay would therefore have to be brought separately from proceedings claiming the interim payment. It was held that the language of the clause in question was not clear enough to exclude the common law right of set off and that the defendant was entitled to pursue that cross claim as a defence in the action.