Last edited 11 Jun 2017

Liability for building design


[edit] Introduction

Design is carried out by a range of construction professionals; the architect, structural engineer, services engineer, and more recently, specialist consultants (such as IT consultants), specialist contractors, subcontractors and suppliers. The design will be described in drawings, plans, specifications, building information models and by the selection of construction methods and materials.

Design liability determines the standard of care that must be applied by the designer. English law and statute (Section 13 of the Sales of Goods and Services Act 1982 as amended by the Sale and Supply of Goods Act 1994) provides that the designer must carry out the design services with reasonable skill and care. This is analogous to the duty of care in negligence. In the case of Bolam v Friern Hospital Management Committee, the court applied the following test:

'.....where you get a situation which involves the use of some special skill or competence....( a designer) need not possess the highest expert is sufficient to exercise the ordinary skill of an ordinary competent man exercising that particular art '

The Bolam case was concerned with medical negligence however it is clear from subsequent court decisions that the test applies to the design function in construction projects.

[edit] General considerations

Whilst design liability will always depend on the particular facts and circumstances of any situation the following commentary can be made in relation to the duty to design with reasonable skill and care:

  • An error of judgement or choosing an incorrect method of construction will not necessarily be a breach of the designers duty, particularly if there is conflicting professional opinion.
  • A designer cannot rely on the test of 'ordinary competency' to lower a higher duty arising from particular facts or knowledge.
  • A designer may be able to rely on the 'state of the art' defence, ie the standard of care depends on what was expected of the competent designer at the material date (the date of the design). Even pioneering designers have to be prudent. In Independent Broadcasting Authority v EMI Electronics Ltd and BICC Construction Ltd, the court held that even though the design and construction of a cylindrical communications mast was '...both at and beyond the frontiers of professional knowledge at that time it was still incumbent on (the designer) to exercise a very high degree of care'.
  • A specialist designer does not, as such, have a higher duty although a specialism may be relevant to the forensic analysis, ie should more care be expected from the specialist?
  • Designers should take reasonable steps to keep themselves up to date with new methods and materials.
  • The designer is not responsible for elements of the design delegated to other consultants, the contractor or specialist sub-contractors and suppliers, where these parties contract direct with the client. However the designer will be responsible where there is a delegation of the design function to the designer's own sub-consultant or sub-contractor.
  • When a faulty design is imposed on the designer by the client, the designer will not be liable if the designer has given sufficient warning to the client.
  • The client's approval of the design does not relieve the designer of design liability for structural failures although there may be a defence to issues of function, amenity, aesthetics and possibly, commercial objective.
  • The design obligation is a continuing duty up to practical completion.
  • The duty of reasonable skill and care in tort can run concurrently with contractual obligations.
  • The duty of reasonable skill and care can be restricted (subject to the Unfair Contract Terms Act 1997) or extended by contract agreement.
  • In the absence of a contract, a design liability may arise in tort by reason of a duty to warn. This duty arises when a reasonably competent contractor should have realised that a design or elements of the design were likely to be defective.

[edit] Design and Build Contractors

Subject to the express terms of the contract, there is an implied term that the design and construction will be fit for its purpose provided there is reliance by the client on design decisions taken by the contractor, for example, there is no reliance if the client insists on a particular construction method or material which subsequently fails.


  • Greaves & Co ( Contractors) Ltd v Baynham Meikle and Partners.
  • George Hawkins v Chrysler (UK) Ltd and Burn Associates.

[edit] Dwellings

Section 1 of the Defective Premises Act 1972 provides that a contractor building a residential dwelling or converting or enlarging an existing dwelling, has a statutory duty to ensure that the building work ' done in a workmanlike or, as the case may be, professional manner with proper materials and so that as regards the work the dwelling will be fit for habitation when completed'

The obligation is a statutory duty and exists without the need for a contract between the house owner and the contractor and for the benefit of future owners. However the duty will not apply if the dwelling is covered by the NHBC Scheme.

Claims must be made no later than 6 years after completion of the work or any remedial work carried out by the contractor to rectify defects in his original work.

[edit] Building Information Modelling (BIM)

As an interactive, collaborative, multi-partite, virtual design process, Building Information Modelling (BIM) creates a complex design liability scenario, often with subsidiary models feeding into a master coordinating model. For BIM, to be collaborative and fully effective, it needs to overarch the usual vertical bi-partite contractual structure of the design obligation (e.g. a specialist subcontractor design obligation will be set out in the subcontract with the main contractor who in turn sets out his responsibility with the client in the main contract).

Bypassing the certainty of this contractual structure could give rise to complex design liability issues, such as claims arising from the different duties of reasonable skill and care and fitness for purpose, software glicthes, breach of the duty to warn, conflicts over insurance cover, claims under the Contract ( Right of Third Parties ) Act 1999 or contribution disputes under the Civil Liability ( Contribution ) Act 1978.

The importance of BIM to the design process is huge, and so it is crucial that effective protocols are agreed for its use. Unfortunately, to date, none of the standard form contracts in the UK have dealt with this issue (although the new Joint Contracts Tribunal (JCT) Public Sector Supplement does include references to BIM protocols).

Until they do it is advisable to agree a BIM schedule or addendum setting out the legal status and management of the model or models which must then be incorporated into all contracts having a design element for the project.

The UK is short on BIM guidance, but helpful and adaptable examples can be found in the US:

In the ConcensusDocs 301 and the Architects Doc E202, both the contributors and the model element authors have a continuing duty to report design risks and failures.

[edit] Find out more

[edit] Related articles on Designing Buildings Wiki

[edit] External references

  • Keating Chambers: Professional negligence in the construction field.
  • NHBC.
  • Keating Chambers: Duties of Care in the Construction Field.
  • Greaves & Co ( Contractors) Ltd v Baynham Meikle and Partners.
  • George Hawkins v Chrysler (UK) Ltd and Burn Associates.


To start a discussion about this article, click 'Add a comment' above and add your thoughts to this discussion page.