It’s trite law that an entitlement to compensation flows where someone’s negligence has caused you damage. But sometimes things aren’t quite as simple as they seem. You always have to find out exactly what loss was caused by the negligence and compensate only for that. If you drive your car backwards into a brick wall and cause a lot of damage, the cyclist that comes along later and breaks the last remaining light on the back of the car is not going to be liable for the totality of the damage to your vehicle. That’s probably all pretty clear but sometimes it’s a bit less straightforward.

In BPN & NPS v Canham [2021] the court was asked to rule on a professional negligence claim. It was common ground between the parties that the designs for the foundations for two separate terraced blocks had been negligently drawn and that the foundations were inadequate. The defendants argued that the costs of remedial work to the foundations were limited and that the works could have been completed satisfactorily. Indeed repair work to one of the blocks had begun before a decision had been taken that both should be demolished as the structures were anyway of very poor quality. The claimants sought 3.7 million for the cost of the demolition and rebuilding and some other consequential losses.

The defendants argued that they were liable only for the costs of remediation of their negligence. The courts had to look at the issue of causation and decide the extent of the defendant’s liability.

It transpired that revised drawings produced by the defendants with a better specification had not been given to the original builders, that the blocks had been constructed with a number of other defects unrelated to the original defective drawings and that generally the buildings were so poor that they would have had to be demolished even had the defendants not made an error.

In the circumstances the judge found that the need to demolish the building had not flown from the negligence, causation had not been made out and that damages should be the cost of the required repairs to the foundations only – amounting to £2,000. Quite a reduction on the original claim and a salutary lesson to remember causation!!