Duty to Review Design

There is case law which suggests an architect or engineer has an ongoing duty to review their design.

The architect is under a continuing duty to check that his design will work in practice and to correct any errors which may emerge.  It savours of the ridiculous for the architect to be able to say: ‘True, my design was faulty but of course, I saw to it that the contractors followed it faithfully’ and to be enabled on that ground to succeed in the action.[1] 

There is authority that duration of the duty continues beyond practical completion until the works are truly complete.[2]

The extent of this duty is not set out in a statute but comes from precedent drawn from a number of decided cases.  There is some debate as to whether this duty arises as a matter of course or due to a specific event during a project. 

Archie, having designed a wall in 1990 which would not adequately resist driving rain, goes onto site in 1992 when the builder starts to construct the wall.  The building is completed in 1995 and is subject to driving rain, which causes leaks in 1997.

When he goes on site, Archie sees his design being built and has an opportunity to recognise and correct his error but does not do so.  This failure to correct his earlier error is a negligent action, in respect of which a claim for damages could be brought. 

If it is seen as a renewal of his earlier error, it may be argued that the limitation period for a claim for the design error runs from 1992 not 1990.  If it is a new and distinct error, there may be some difficulty in sustaining a worthwhile claim against him.  Arguably, the new error cannot cause a loss, the loss already having been caused by the earlier negligence in design.  The amount claimable for damages is based on the loss caused.  Logically, the second error, however reprehensible, is not the cause of the loss for the negligent design and causes no additional loss because, at the time the second error was made, all of the loss was already an inevitable consequence of the earlier error and, if that earlier error had not been made, the second error could not exist.

Correcting a design error, apart from the additional work done by the designer, may not result in any loss if done early enough.  A correctly designed wall may not cost more to build than an incorrectly designed one.  Therefore, finding and correcting the error before the wall is built to an incorrect design may occasion no loss.  Once construction is commenced, the cost of correcting the error is likely to increase as work progresses and to reach a maximum once the building is finished and occupied.  If it is accepted that there is a continuing duty to review, delay in finding the error can be said to increase the loss.

The above example deals with the assumption that there is a deemed duty to review design, i.e. that this duty exists regardless of events and despite the silence of the designers’ terms of appointment on this subject.  It is as if the designers of buildings had some overriding duty to review their designs every day until construction was finished.


[1]  L.J. Sachs in Brickfield Properties v Newton (1971) 1 WLR 862, p. 873.

[2]  Judge Bowsher Q.C. in University Court of Glasgow v Whitfield (1988) 42 Build LR 66.