In a claim brought by a developer for the defective design of a tower block where no physical damage had occurred, the designer owed the developer a duty of care notwithstanding that the developer had sold the individual flats before the design defect was discovered. The cause of action for economic loss accrued at the time of practical completion, when the defective structural design had been irrevocably incorporated into the buildings. There was nothing to prevent the developer from bringing a further claim against the designer under the Civil Liability (Contribution) Act 1978 s.1(1), even though no claims had been brought against the developer by the purchasers of the flats. The ruling has made it easier for developers of residential buildings that have incurred costs in remediating unsafe dwellings to recover such costs from those that carried out the defective works. Confirms that the extended limitation periods introduced by the Building Safety Act 2022 have retrospective effect, and apply even to claims that are already the subject of live proceedings.