Melinda Parisotti - A contractor has a duty to point out errors and dangers in a client's design or instructions. But just how far does that duty go?
You are enjoying a splendid evening at a formal social event when suddenly you are faced with an unfortunate dilemma. You notice that a charming gentleman standing next to you, who has clearly got ready in a hurry, has shaving foam in his ear. Do you discreetly advise him of the problem? Or do you just slope off quietly and hope someone else has the courage to point it out? I suspect that sloping off would be the more attractive option to the vast majority of us because most of us are miserable cowards at heart.

But can the same "blind eye" approach be adopted by the contractor on a building site? If the contractor notices that the design or other instructions contain an error, does it have a duty to draw that to the attention of the client? Or can it opt for the easy life by staying quiet? Plant Construction Plc vs Clive Adams provides some of the answers. Here, the subcontractor was found liable for failing to warn the main contractor that the instructions for the subcontract works posed a serious threat of personal injury.

This case confirmed the growing trend over the past 15 years or so to find that a contractor (or subcontractor) does, indeed, have a duty to warn of defects in the design that pose a danger. However, the court deliberately left open some important issues on the subject.

First, the court did not identify just how far the duty goes. If the contractor's warning is ignored, must it go so far as to resign from the job? The court also declined to determine whether the liability to warn still exists if there is no actual threat to the person, but the threat, instead, is to property. There is very little guidance elsewhere on this point, so it seems destined to remain unresolved until someone with plenty of courage and even more money takes the issue to court at a future date.

Their Lordships left a third issue unresolved: whether the subcontractor would still have been liable if it did not have knowledge of the problem, but in the circumstances should have been aware of it.

A contractor has, in the past, been found liable in such circumstances (Lindenberg vs Canning), but it seems that this "knowledge" in the objective sense is not readily found by the courts. In the Aurum case discussed by Tony Bingham (pages 48-49), it was determined that the contractor must at least be aware of all the surrounding circumstances from which the danger might be inferred. Certainly, it seems the contractor is not expected to carry out an extensive examination of the design to look for any hidden errors.

A clear duty to warn of defects that any contractor should spot could save time, money and litigation

So the law is a rather murky shade of grey on the question of a contractor's duty to warn of errors about which it should have known, but is not proven to have known. But surely a contractor should have such a duty? For a start, it is usually extremely difficult to prove actual knowledge, even where it exists. The fact that any reasonable contractor would have been alerted to the problem in the circumstances should surely be sufficient. Otherwise, the law is effectively punishing the astute and responsible contractor that correctly interprets the signs and asks the right questions to identify the problem.

Meanwhile, the idiot who allows it all to pass over his head would be saved by his own stupidity, and the uncooperative contractor would be saved by its reluctance to help out. That cannot make sense.

Besides, in the new construction climate of co-operation, partnering, working for the common good, and general bonhomie all round, contractors should be encouraged to ask questions. They should be willing to become involved by drawing attention to potential difficulties, rather than adopting a blinkered view on the grounds that it is simply not their problem. A clear duty to warn of defects that any reasonable contractor should have spotted (including, for that matter, those that only pose a threat to property rather than people) could result in huge savings in time, money and litigation for those involved. And the price for the contractor? Comparatively very little inconvenience or embarrassment in the vast majority of cases.

Hopefully, at the next opportunity, the courts will find accordingly in the interests of construction as a whole.