Expert fees on ten-year construction liability and decennial insurance claims

Two kinds of client, two kinds of mandate

On ten-year claims the expert may act for the building owner, who claims under a decennial or latent defects policy, or for a contractor or designer facing a recovery action after the insurer has paid. Owners more often accept success-based fees; contractors and their liability insurers usually pay defence experts by the hour.

In both cases the work includes reviewing the policy and the period of cover, the original design and technical inspection reports, investigating the structure, establishing when damage first appeared, defining and costing a lasting repair, attending joint expert meetings and negotiating the settlement or contribution.

Indicative percentage bands for owner claims

The table below sets out an indicative order of magnitude observed on the market for owner-side experts on structural claims, not an official scale. It is shown in euros because decennial regimes are mainly found in civil-law countries and Ireland uses the euro; advisers in the UK, US, Canada and Australia tend to apply comparable bands in local currency, with significant variation.

In France, where decennial insurance originated, policyholder experts refer to a published professional scale running from 9 percent up to 25,000 euros, then 8, 7, 6, 4.5, 3.5 and 2.5 percent across higher bands, and 1 to 1.75 percent above two million euros. It is a professional reference, not a legal tariff, and other markets have no direct equivalent.

Indicative amounts, to be checked with each expert.

Calculation bases and billing methods

Because long-tail claims can take years, the fee basis should be fixed precisely at the start.

• Percentage of the total indemnity, including the value of repairs carried out directly by the insurer if the engagement says so.
• Percentage of the improvement obtained over the insurer's initial offer or proposed repair scheme.
• Hourly or daily rates for structural, geotechnical and building pathology specialists, typically higher for expert witness work.
• Stage fees: a fixed price for the initial diagnostic opinion, then a separate agreement for the claim itself.
• Retainers on very long files, credited against final fees.

Taxes, minimum fees and investigation spending

Check whether quotes include VAT or local equivalents, and whether a minimum fee applies. Long-tail cases often require monitoring for months, geotechnical boreholes, laboratory testing of concrete or steel, and translation of documents on international projects. These disbursements can be substantial and should be estimated and capped where possible.

Factors that push the price up or down

The single biggest driver is uncertainty about cause. Where the insurer accepts that a foundation or structural defect exists and the debate is only about repair cost, the file is shorter and a lower rate is justified. Where the insurer argues that maintenance failures, later alterations or nearby works are responsible, the expert must commission more investigation and produce a reasoned technical rebuttal.

Other factors include the number of units or occupants affected, the age of the building and the quality of surviving records, the need for rehousing calculations, whether a technical inspection firm's reports support or contradict the owner, and whether the project lies abroad, which adds travel, translation and familiarity with local procedures. Proximity to the end of the cover or limitation period also adds pressure, because work must be compressed into a shorter window.

Is any of this paid by the insurance?

Decennial and latent defects policies generally cover the cost of repairing qualifying structural damage, and many include associated professional fees for design and supervision of the remedial works. Some also pay for investigation needed to establish the cause once a claim is accepted. Fees for an owner's adviser who disputes the insurer's position are usually not covered, unless a specific extension applies.

For contractors, a professional or general liability policy may fund defence experts as part of defence costs, subject to the insurer's consent and its own panel arrangements. Always ask before appointing an expert whether the cost will be treated as covered.

Cost examples from small to major structural claims

Small: localised settlement in a single house needing €30,000 of foundation works. An owner-side expert charging a minimum fee or about 10 percent would cost roughly €3,000, with monitoring billed separately. If the insurer accepts the claim quickly, a fixed diagnostic fee may be all that is needed.

Medium: water penetration through a defective roof structure across an office building, with remedial works of €450,000. At an indicative 5 to 7 percent, the fee would be around €22,500 to €31,500, plus perhaps €8,000 to €15,000 in investigation costs.

Large: foundation failure on a residential tower abroad requiring €8 million of works and rehousing. Percentage rates commonly fall to 1.5 to 2.5 percent, giving €120,000 to €200,000, and the contractor's defence experts on the recovery side may bill comparable sums on an hourly basis.

Comparing proposals and avoiding pitfalls

Structural cases demand specialist knowledge, and on international projects familiarity with the local decennial regime and language. Compare proposals on equal terms rather than on the headline rate.

• Request evidence of past structural or decennial claims and the qualifications of the engineers involved.
• Check independence from the insurer, the technical inspection firm and the original contractor.
• Ensure the engagement explains fees if the claim is time-barred, declined or resolved by repair rather than payment.
• Agree regular cost reporting for files likely to last more than a year.
• Distrust any adviser promising certainty about cause or settlement before investigations are complete.

On ten-year liability claims, splitting the diagnostic stage from the claim mandate and capping investigation costs keeps fees proportionate. With these safeguards, independent expertise is usually a sound investment against a structural loss.