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Buildability: design and responsibility

Buildability can be defined as the extent to which the design of a building facilitates the ease of construction. It is whether the building design can become a reality.

However, there are many factors that can compromise a successful outcome to a project, including design over-sights and omissions.

Under a traditional procurement contract structure, the employer appoints each design consultant and contractor under separate and distinct contracts. Despite this structure, a review of current case law makes it clear that a contractor’s responsibility is not entirely removed in terms of the buildability of the design (including any omissions of crucial elements or deficiencies).

The case of Thorn v The Mayor and Commonalty of London (1876) 1 App Cas 120 states that there is no implied warranty from an employer that a project (in this case, a bridge over the Thames) could be built in accordance with the drawings and specifications produced on the employer’s behalf. In this case, the judge held that the contractor “ought to have informed himself of all particulars connected with the work and especially as to the practicability of executing every part of the work contained in the specification“.

In practice therefore, the contractor is obliged to expend time in reviewing the specifications and analysing the buildability of the project. This is a huge burden for a contractor to bear and one which they may not even have the capability or resources to undertake. Negotiation of terms allocating such risk between the parties at the outset of the project is therefore crucial.

There are some key actions and arguments that the parties may consider to mitigate and/or recover losses in terms of design buildability:

  1. negotiate an appropriate contractual risk matrix to establish which party is responsible for buildability design risk at the outset of the project. This will reduce the chance of disputes in future;
  2. consider novating the design consultants to ensure that the contractor has contractual recourse against the design consultants if they are found responsible for defective design. This also puts the employer in the optimum position where they do not carry responsibility for the design buildability risk;
  3. contractors can claim that the additional work required for overcoming the design buildability deficiency was executed outside the construction contract. While this may be an option for a contractor, a well-drafted contract can include bespoke terms to protect an employer from such claims;
  4. contractors may claim breach of the engineer’s duty of care owed to the contractor in relation to the design (as per Galliford Try Infrastructure Ltd. V. Mott MacDonald Ltd [2008] EWHC 1570). A sound contract structure and legal advice can ensure that the contractual links are in place to minimise loss and improve recovery for the relevant parties.

Commercially, the contractor should consider the implications of buildability design risk against its tender price and future defective design responsibility, and the likelihood of being successful in the tender. If the implications are too great, a contractor may opt out of tendering all together. Employers should bear this in mind when issuing contracts as part of a tender pack.

From an employer’s point of view, there is also benefit in increased early contractor involvement in a project at the design stage. This early collaboration can help optimise the construction design and minimise time and cost of construction.

If you would like advice in relation to your contractual obligations and how to minimise your contractual risk profile, please contact Priscilla Hall, Partner, or any member of Clarke Willmott’s construction team.