There are relatively few cases on the subject of what warnings professionals need to give to their clients when advising/acting for them. In a case that came before Akenhead J in the TCC this March, the following guidance was given. Clearly much will depend upon the expert evidence and any contracts in such cases, but it is still worth bearing in mind this summary on a common yet surprisingly misunderstood area:
“(a) Where the professionals (engineers in this case) are contractually retained, the Court must initially determine what the scope of the contractual duties and services were. It is in the context of what the professional person is contractually engaged to do that the scope of the duty to warn and the circumstances in which it may in practice arise should be determined.
(b) It will, almost invariably, be incumbent upon the professional to exercise reasonable care and skill. That duty must be looked at in the context of what the professional person is engaged to do. The duty to warn is no more than an aspect of the duty of a professional to act with the skill and care of a reasonably competent person in that profession.
(c) Whether, when and to what extent the duty will arise will depend on all the circumstances.
(d) The duty to warn will often arise when there is an obvious and significant danger either to life and limb or to property. It can arise however when a careful professional ought to have known of such danger, having regard to all the facts and circumstances.
(e) In considering a case where it is alleged that the careful professional ought to have known of danger, the Court will be unlikely to find liability merely because at the time that the professional sees what is happening there was only a possibility in future of some danger (see Aurum); any duty to warn may well not be engaged if all there is a possibility that the contractor in question may in future not do the works properly.”
Paragraph 47 of Goldswain & Anor v Beltec Ltd (t/a BCS Consulting) & Anor  EWHC 556 TCC