NOTE Nº 0636 · REV B

Contract vs Negligence: Building Claims Compared

When to sue a builder in contract and when in negligence: the pure economic loss rule, claims against surveyors and engineers, and how the routes combine.

By The Renovation Notes Team · 4 min read · Published 29 August 2026 · updated within the last month · Sources checked 30 September 2026

A high-rise building with scaffolding for construction and repair work under a clear sky.

In short

Against your own builder, contract is almost always the claim: negligence generally can't recover the cost of fixing defective work itself (pure economic loss) unless the defect damages other property or people. Negligence earns its place against professionals, surveyors, engineers, architects, where advice causes loss, and in the late-discovery zone where the Latent Damage Act keeps claims alive after contract time has run.

“I’ll sue them for negligence” is the phrase every angry homeowner reaches for, and in building cases it’s usually the wrong tool pointed at the right target. English law splits building claims between two tracks with different rules, different clocks and different defendants. Choosing correctly is half the battle; here’s the map.

Contract: the default against your builder

Where you hired them, the claim is for breach of contract, the express terms plus everything the Consumer Rights Act implies: reasonable care and skill, price, time.¹ Contract recovers the full expectation: the cost of putting the work right, plus consequential losses. Six years from the breach, procedural route via the normal escalation.² Simple, complete, and why every guide in this series pushes the paperwork: the contract is the claim.

Negligence: powerful, but allergic to defects

Negligence (a duty of care, breached, causing loss) has a rule that surprises everyone: in construction, the courts treat the cost of repairing the defective work itself as “pure economic loss”, and pure economic loss is generally not recoverable in negligence from a builder.³ The defective extension is, legally, just a bad bargain; bad bargains are contract’s business (this is the Murphy v Brentwood line of authority, in one sentence).³

What negligence does reach:

Damage to other property and injury to people, the badly-fixed tank that ruins the (separate) original house contents; the collapsing wall that hurts someone. Fully claimable in negligence, including by people with no contract at all, the visiting relative, the neighbour.
Professional advice, below.
Statutory routes sit outside both tracks: the Defective Premises Act recovers repair costs for habitability-level defects without any contract, which is precisely why it matters.⁴

Where negligence earns its keep: the professionals

Surveyors, engineers, architects and valuers give advice and design, and negligent advice causing financial loss is the classic professional negligence claim (the main exception to the economic loss rule: a professional who assumes responsibility for advice or design owes a duty of care against financial loss).³ The survey that missed the subsidence; the engineer’s beam that was undersized; the architect’s detail that couldn’t keep water out. You’ll often have a contract with these professionals too (claim in both, in the alternative), and negligence extends to some non-clients who foreseeably relied.³ Architects are expected by their regulator to hold professional indemnity insurance and RICS-regulated firms must hold it; that cover is what makes a judgment collectable, so ask any professional you instruct to confirm theirs.⁵⁶ The standard is the competent professional of that discipline, proven by an expert of the same discipline.

The late-discovery zone

The second reason negligence exists in your toolkit: time. Contract dies six years from the work; negligence runs from damage, and the Latent Damage Act adds three years from discovery with a 15-year longstop.⁷⁸ Defects surfacing in years 7–15 are routinely pleaded in negligence against the professionals in the chain (design and advice claims fit the rule) even though the identical complaint against the builder would fail the economic-loss test. It’s untidy, it’s the law, and it’s why “who can I still sue?” late in the day needs a solicitor’s hour rather than a guess.

Choosing in practice

Your own recent builder, defective work → contract. Someone else’s builder, serious defects → DPA. A professional’s bad advice or design → professional negligence (plus contract if they were yours). Physical damage beyond the works, or injury → negligence against whoever caused it. Old defects → limitation analysis first, everything else second. Plead in the alternative where routes overlap, the law lets you, and the construction law pillar shows the whole board.

This guide is general information for homeowners in England and Wales, not legal advice.

References (8)

Figures in this note were checked against the sources below on 30 September 2026. Superscript numbers in the text point to them. Every source the site cites, by topic.

1technicalvery strongThe National Archives (legislation.gov.uk), guidance.RN-AWCFS4The services chapter of the Consumer Rights Act 2015. Sections 49, 51 and 52 imply terms that a trader uses reasonable care and skill, charges a reasonable price where none is fixed, and performs within a reasonable time.
2technicalvery strongThe National Archives (legislation.gov.uk), legislation.RN-L5C0B9Section 5 of the Limitation Act 1980: an action founded on simple contract cannot be brought more than six years after the cause of action accrued. This is the six-year limit on suing a builder over a contract that was not executed as a deed, and it runs from the breach, not from when the defect was discovered. The single most important date in a dispute about defective work.
3technicalvery strongThe National Archives (Find Case Law), guidance.RN-QD0JG3Supreme Court judgment on a negligent structural design claim. Paragraph 27 explains that the loss from a defective building needing repair is pure economic loss, and that in general no duty of care in negligence protects against it.
4technicalvery strongThe National Archives (legislation.gov.uk), legislation.RN-TD41J9Section 1(1) imposes a duty on anyone taking on work for or in connection with the provision of a dwelling, whether by erection, conversion or enlargement, owed both to the person to whose order the dwelling is provided and to every person who later acquires a legal or equitable interest in it, to see that the work is done in a workmanlike or professional manner, with proper materials, and so that the dwelling will be fit for habitation when completed. Section 1(2) treats a person working to another's instructions as discharging the duty to the extent the work follows them properly, except where they owed and failed in a duty to warn of defects in the instructions; section 1(3) says merely agreeing to a specified manner, materials or design is not giving instructions. Section 1(4) brings a business that arranges for another to do the work within the duty. Section 1(5) fixes the accrual of the cause of action at the date the dwelling was completed for Limitation Act 1980 purposes, with a fresh accrual for any later rectification work when that further work is finished. The duty runs to subsequent owners, which contract claims do not.
5technicalstrongRICS, guidance.RN-J5WELHRICS regulation page quoting the Rules of Conduct: RICS-regulated firms must carry professional indemnity insurance meeting RICS minimum terms, from a listed insurer.
6technicalstrongArchitects Registration Board, guidance.RN-GIF8CWThe Architects Registration Board's guidance on professional indemnity insurance. Sets out that a registered architect must hold adequate and appropriate cover for their liabilities, what the Board expects the policy to cover, and run-off cover after a practice closes. This is what to check before engaging an architect, and the reason an architect's fee carries an insurance cost a draughtsman's does not.
7technicalvery strongThe National Archives (legislation.gov.uk), legislation.RN-NT0BCVSection 14B of the Limitation Act 1980 is the absolute cut-off for negligence claims against a builder, designer or engineer where no personal injury is involved. Subsection (1): an action for damages for negligence, other than one to which section 11 or 11ZA applies, shall not be brought after the expiration of fifteen years from the date, or if more than one from the last of the dates, on which there occurred any act or omission alleged to constitute negligence and to which the damage is alleged to be attributable. The fifteen years runs from the negligent act itself, not from the date the homeowner discovered the problem, and it overrides the more generous three-year date-of-knowledge extension in section 14A. In practice a latent defect discovered sixteen years after the work was done is out of time in negligence however reasonable the delay in noticing it.
8technicalvery strongThe National Archives, guidance.RN-MHLPHLThe latent damage rule inserted by the Latent Damage Act 1986: a negligence claim for damage other than personal injury may be brought within six years of accrual or three years from the date of knowledge, whichever is later.