The Limitation Act 1980 sets the ordinary time limits within which a professional negligence claim can be brought. Section 2 gives a claimant six years from the date the cause of action accrues to bring a claim in tort; section 14A extends that period to three years from the date on which the claimant first had knowledge of the relevant facts; and section 14B imposes a 15-year long-stop from the negligent act or omission itself. For most professional indemnity claims against architects and other design professionals, this framework has for decades defined the outer edge of the run-off risk that a practice needed to insure against.
The Building Safety Act 2022, and in particular section 135, has rewritten that boundary for one important category of work.
Section 1 of the Defective Premises Act 1972 imposes a duty on those taking on work in connection with the provision of a dwelling to ensure the work is done in a workmanlike or professional manner, with proper materials, so that the dwelling is fit for habitation when completed. Before June 2022, a claim under section 1 of the DPA had to be brought within six years of the date the dwelling was completed. In practice this meant that any DPA exposure on a residential design was effectively closed off six years after practical completion.
Section 135 of the Building Safety Act 2022 amended the Limitation Act 1980 in respect of DPA section 1 claims. Two distinct regimes now apply:
The DPA applies to dwellings. Purely commercial buildings do not fall within section 1, although mixed-use schemes with a residential element will. The extended limitation regime therefore bites hardest on architects, engineers, and design-and-build contractors whose portfolios contain residential blocks, mixed-use developments, and higher-risk buildings.
Because the retrospective provision took effect on 28 June 2022, work completed from 28 June 1992 onwards potentially falls within its scope. A design that was completed in 2010, and that under the pre-BSA regime would have been out of DPA limitation by 2016, is now potentially claimable until 2040. That is a 24-year expansion of the tail on a single project.
In URS Corporation Ltd v BDW Trading Ltd [2023] EWCA Civ 772 the Court of Appeal considered how the transitional provisions of the Building Safety Act operate. The court confirmed that the retrospective extension in section 135(1) applies to accrued causes of action that would otherwise have been time-barred, and that this reaches into positions the parties may have previously treated as settled. The judgment reinforced that the extended window is not a narrow drafting curiosity but a substantive reopening of long-tail exposure.
Worked example: an architectural practice designed a residential block completed in 2005. The partners retired in 2020 and, on the advice they took at the time, purchased a six-year run-off policy expiring in 2026. Under section 135(1) of the Building Safety Act 2022, a DPA section 1 claim in respect of the 2005 design is now time-barred only in 2035 — 30 years from completion. The six-year run-off ends in 2026, nine years before the limitation window closes. The practice is exposed for nearly a decade on a project it can no longer service, without the professional indemnity policy in place to respond.
The six-year run-off that was, for many years, the industry default is now materially inadequate for practices whose historic work includes residential dwellings, and particularly higher-risk buildings within the meaning of the Building Safety Act. Design professionals looking to close a practice, retire, or restructure need to consider extended run-off periods, alternative funding vehicles, or the position their successor practice can offer. Practices still trading need to keep the DPA exposure in mind when reviewing limits of indemnity at renewal, and when reading the wording of insuring clauses and exclusions relating to fire safety, cladding, and higher-risk buildings.
Apex Insurance Brokers arranges professional indemnity cover for architects, engineers, and design-and-build contractors, and can review the interaction between a firm's historic residential portfolio and its current or run-off PI arrangements. Related guides on this site include the architects' PI guide, the engineers' PI guide, and the design-and-build contractors' PI guide. Related wiki entries include Building Safety Act 2022: architect PI implications and Limitation Act 1980 section 14A and professional negligence.
Apex Insurance Brokers Limited is authorised and regulated by the Financial Conduct Authority. Firm reference number 724952. This entry is general information, not advice on any particular policy.