To say otherwise would be ‘contrary to principle and wrong’, in the view of the English Court of Appeal. The argument was made in Keay v Morris Homes (West Midlands) Ltd,  EWCA Civ 900, where the plaintiffs claimed damages for alleged breach of an oral agreement for prompt completion of building works following a sale of land. Morris Homes argued that it had never made such an oral agreement and that, even if it had, the agreement was void because it failed to comply with the Law of Property Act (Miscellaneous Provisions) Act 1989. The statute requires contracts involving the sale of land to be incorporated in a signed document; the works obligation was supplementary (not collateral) to the land-transfer agreement, and was thus void for not having been part of the land transfer. The plaintiffs countered with the argument that the practical completion of the land elements of the contract caused the void, non-land elements to become enforceable.
The Court of Appeal found this a ‘surprising’ argument, and a misapplication of some admittedly difficult earlier case law. The omission of the supplementary works obligation from the main contract rendered it a nullity or at most a proposed contractual term that had never been incorporated into a valid contract. It was in any event unenforceable.
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