Professional Indemnity Insurance: Who Needs It and When

‍‌‌‌​​​​​​‌‌‌​‌‌​‌‌‌‌​​‌​‌‌‌​‌​‌‍SiteKiln gives you plain-English information, not personal insurance, financial or legal advice. If you need advice specific to your situation, talk to a qualified insurance broker or solicitor.

6.3.1 The short version

Professional indemnity (PI) insurance covers you when a client says your advice, design or professional judgement has cost them money and they want you to pay for it. It picks up legal costs and compensation for financial loss arising from errors, omissions or professional negligence, even if the work finished years ago.

You do not need PI just because you do manual work. You need it when you move into design, specification, layout advice or signing things off -- or when a contract or professional body says you must have it. On most pure "labour-only, built exactly to the engineer's drawing" jobs you can live without PI; on design & build, structural advice and higher-end work it becomes critical.

6.3.2 Why it matters

A bad design decision can be far more expensive than a bad day on the tools. Getting a beam size wrong, mis-speccing a waterproofing detail or giving poor drainage advice can easily lead to tens or hundreds of thousands in remedial costs and loss of use claims. Clients will come after whoever signed off or "took responsibility", which is often the main contractor or builder, not just the consultant in the background.

PI turns that from a "sell your house" problem into a managed insurance claim. For some professions -- architects, consulting engineers and similar -- it is effectively a licence-to-trade requirement set by regulators and professional bodies. For builders and trades, having PI in the right situations stops one design-related dispute from wiping out years of profit.

6.3.3 What professional indemnity actually covers

At its core, PI covers financial loss caused by your professional services -- advice, design, calculations, specifications, surveys or sign-offs.

Typical construction-type scenarios include:

• You recommend a steel size for a knock-through and it fails building control, requiring redesign and strengthening.
• You set out falls and drainage for a patio or basement, and poor falls lead to flooding and damage.
• You coordinate drawings from a subcontracted designer, they make an error, and the client sues you as the named contractor.

A standard PI policy normally covers:

• Claims for negligence, error, omission or breach of professional duty.
• Legal defence costs, expert reports and court costs.
• Settlements or awards of damages for the financial loss element of the claim.

It usually does not cover:

• Purely physical damage to site works -- that's contract works/all-risks.
• Injury to people -- that's employers' liability or public liability.
• Deliberate wrongdoing, fines or penalties.

PI is almost always written on a "claims made" basis -- it responds when the claim is made against you, not when you did the work, which is why continuity and run-off cover matter.

6.3.4 Who actually needs PI in construction

You should be seriously looking at PI if you:

• Provide or amend drawings or designs (even just mark-ups on architect or engineer drawings).
• Offer anything that looks like professional advice -- structural, layout, waterproofing, drainage or fire strategy suggestions.
• Take on design & build or contractor-designed portions under JCT/NEC where you carry design responsibility.
• Engage your own designers or engineers but remain contractually liable for their work.
• Act as principal designer or lead consultant on a project.

Groups where PI is often mandatory or strongly expected:

• Architects -- ARB and RIBA expect "adequate and appropriate" PI, with guidance suggesting a minimum £250k per claim and run-off cover.
• Consulting engineers, surveyors and many design professionals -- covered by their own professional body codes and client standards.
• Design-and-build contractors -- JCT and other contracts now routinely require PI where the contractor has design obligations.

If you genuinely provide no design or advice -- you build exactly to others' drawings, with no tweaks, value-engineering or spec substitutions -- PI may be unnecessary. But as soon as you start "helping" with design decisions, you are in the firing line.

6.3.5 When contracts and professional rules force it

You often first meet PI as a contract condition rather than something you choose.

Common places it appears:

• JCT and NEC contracts that include contractor-designed portions or full design & build -- they specify that you maintain PI at a set limit for a number of years after completion.
• Consultant appointments, collateral warranties and framework agreements, especially with public-sector and institutional clients.
• Professional body membership rules -- for example ARB's Code of Conduct, which expects architects to keep "adequate and appropriate" PI, including run-off cover.

Contract clauses to watch:

• Required limit (for example "not less than £1,000,000 any one claim").
• Length of time you must maintain PI after completion (often 6, 12 or even 15 years).
• Any specific exclusions or sub-limits (for example fire safety, cladding, basements) the contract says must not appear in your policy.

If a contract demands PI and you sign without having it, you are in breach from day one and effectively self-insuring that risk.

6.3.6 Typical limits and run-off

There is no legal minimum PI limit. What is "enough" depends on your role, project size and contractual commitments.

Typical patterns:

• Small design input on domestic projects -- limits from £250k to £500k can be common.
• Architects and similar professions -- ARB guidance expects at least £250k per claim and more where exposure justifies it.
• Design-and-build contractors on larger jobs -- £1m, £2m, £5m or higher, often set directly by the contract.

Key thing with PI is continuity:

• You need continuous cover year-on-year; gaps can leave past work effectively uninsured.
• When you stop trading or change role, you usually need run-off cover for the limitation period on claims (6-12+ years, depending on contract form).

6.3.7 Common mistakes and false comfort

Things that regularly catch people out:

• Assuming the architect's or engineer's PI covers you. It usually doesn't if the client sues you as the main contractor or "lead".
• Dropping PI as soon as a project finishes, then getting a claim 3-5 years later -- the policy in force when the claim is made is the one that has to respond.
• Taking a cheap PI policy with broad exclusions on fire safety, basements, cladding or structural work that happen to be the risky parts of your jobs.

And on the other side:

• Paying for PI when you do pure labour-only work with no design, no advice and no sign-off obligations, just because a generic sales page scared you.

The test is simple: if a client could plausibly say "your advice or design cost me money", you should be thinking about PI.

6.3.8 Quick PI health check

You probably need to speak to a broker about PI if any of these are true:

• You change drawings, specify products, or give layout/structural advice as part of your normal work.
• You sign contracts (JCT/NEC or consultant appointments) that mention PI, a specific limit, or a number of years you must maintain cover.
• You are ARB-registered, RIBA, or part of another professional body that expects you to hold PI and run-off.
• You rely on "the architect's PI" or "the engineer's PI" without having seen their policy or checked it matches your contract obligations.

If you already have PI, you are in better shape if:

• Your limit matches your biggest realistic claim and your contract requirements.
• You have no gaps in cover going back at least as far as your oldest live project.
• You understand any big exclusions (for example fire safety, cladding, basements) and they do not quietly remove cover for the work you actually do.

6.3.9 What to do next

• If you provide any design, specification or professional advice as part of your work, speak to a broker about PI.
• Check the PI requirements in your current contracts (JCT, NEC or consultant appointments) and make sure your limit and duration match.
• If you already have PI, read the exclusions -- especially fire safety, cladding and basements -- to make sure they do not quietly remove cover for the work you actually do.
• Plan for run-off cover when you stop trading or change role -- PI is claims-made, so gaps leave past work uninsured.

6.3.10 Who to contact

• Your insurance broker -- to arrange or review PI cover and check exclusions (paid)
• FCA Financial Services Register -- fca.org.uk/firms/financial-services-register -- to check your insurer or broker is authorised (free)
• Financial Ombudsman Service -- 0800 023 4567, financial-ombudsman.org.uk -- if you have a complaint about your insurer (free)
• ABI (Association of British Insurers) -- abi.org.uk -- general insurance guidance (free)
• Citizens Advice -- citizensadvice.org.uk -- for general guidance on your rights (free)

6.3.11 Sources and legislation

• Consumer Insurance (Disclosure and Representations) Act 2012 -- disclosure duties when arranging insurance. legislation.gov.uk/ukpga/2012/6
• Third Parties (Rights against Insurers) Act 2010 -- third-party rights to claim against your insurer. legislation.gov.uk/ukpga/2010/10
• Employers' Liability (Compulsory Insurance) Act 1969 -- context for how PI sits alongside other required covers. legislation.gov.uk/ukpga/1969/57

6.3.12 Related guides on this site

• 6.1 Public liability insurance
• 6.5 Contract works / all risks insurance
• 6.10 Insurance for subcontractors
• 6.9 Making an insurance claim
• 7.10 Building regs vs planning permission
• 3.4 Design liability in construction

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