Every building dispute reaches the same fork: your word against the builder’s about whether the work is actually defective. An independent expert is how you leave that fork with the argument settled, often without going anywhere near a courtroom.

What an expert report changes

The moment a chartered surveyor’s report lands, three things happen. The dispute acquires an objective version of the facts, measured, photographed, referenced to Building Regulations and trade standards. The remedial work acquires a number, priced line by line, which becomes the anchor for withholding, negotiation or claim. And the builder learns you’re serious and informed. Many disputes settle soon after a report is shared, because arguing with a homeowner is free but arguing with a chartered professional’s measurements isn’t.

Who to instruct

  • Building surveyor (MRICS/FRICS), the default for workmanship and defects disputes; ask specifically for a defects inspection report, not a homebuyer survey.
  • Structural engineer, where the argument is structural adequacy: beams, movement, foundations (see surveyor vs engineer).
  • Specialist trade experts, damp, roofing, electrics (an EICR from a qualified electrician is a ready-made expert document), gas (Gas Safe engineer’s report).

Choose someone genuinely independent, not your mate, not the firm quoting for the remedial work, with experience of dispute work. Directories run by RICS and the professional bodies list members by specialism.

What it costs, honestly

ReportTypical fee
Focused defects inspection (one issue)£300–£600
Whole-project defects report, costed£600–£1,200
Structural engineer’s written report£500–£2,0001
Full expert witness report (court-compliant)£1,500–£5,000+

A structural engineer’s written report typically costs £500–£2,000, and a simple inspection visit £175–£300.2 The first three tiers do most of the work in most disputes. The court-compliant tier only becomes necessary when litigation is genuinely running, don’t buy it first.

Briefing the expert well

Give a tight instruction letter: the property, the works, the contract and spec, the specific items in dispute, and the questions you want answered (“is the tiling installation in accordance with BS 5385 and the contract specification? If not, what remedial work is required and at what cost?”). Hand over the evidence file, photos, correspondence, quotes. What you must not do is coach the conclusion: a report that reads as bought advocacy is worthless at every later stage, and a good expert will tell you frankly when some of your complaints are within tolerance. That credibility is what you’re paying for, including the times it trims your own claim to what’s defensible.

Experts and the court

If the dispute reaches proceedings, expert evidence runs by different rules. You need the court’s permission to call an expert or rely on their report.3 The expert’s overriding duty is to the court, not to whoever pays.3 Outside the small claims track, the report must be verified by a statement of truth in a form the rules prescribe.4 On the small claims track no expert may give evidence without the court’s permission, the court can direct a single joint expert instructed by both sides, and the expert fees you can recover from the other side are capped at £750 per expert.56 Practically: get your pre-action defects report early (it powers settlement), and let the court stage dictate any upgrade to full expert-witness format.

The settlement move

Share the report with a letter before action and a simple offer: complete the remedial schedule within X weeks, or pay the report’s remedial figure. You’ve now handed the builder a professionally-priced exit and made every alternative worse for them. That, not the courtroom, is where expert reports earn their fee.

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

References (6)

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.

  1. 1costsupplier figureThe Beam Doctor.RN-DVQUAAA price, true at 2026-09. A chartered structural engineering practice in West Yorkshire publishing its own fee schedule for domestic work, priced by scope rather than by the hour: steel beam and RSJ calculations from 295 pounds and a two or three beam bundle from 495, both desk based from drawings and photographs with any site visit charged separately; a written structural report on one concern from 450; extension design from 650, with larger or multi-storey projects at 800 to 1500 and a bundle of extension design plus one half day site visit at 995; loft conversion design from 450 for a straightforward loft, 1200 to 1800 for larger dormers, hip to gable conversions and trussed roofs that have to be replaced, and 1800 to 2200 for mansards; chimney breast removal from 395 single storey, 550 multi-storey or party wall stacks, 695 for a full stack and 450 for retrospective certification; retaining wall design banded by retained height from 650 to 1400; drainage and build-over support from 275, with build-over or build-near agreement support from 495; and a new roof structure from 600. Site attendance is a separate three tier schedule: 250 for up to two hours, 395 for a half day and 595 for a full day, free of travel charge within 10 road miles of Huddersfield, 45 pounds flat to 25 miles and 45p a mile plus 45 pounds an hour beyond it, with 30 per cent added out of hours. All prices are gross because the practice is not VAT registered. It is one practice's price list, not a market average, and the desk based fees carry no travel so they do not vary with where the house is.
  2. 2costfairHomeOwners Alliance, guidance.RN-6O3Y7XA price, true at 2026-09. HomeOwners Alliance on structural engineer costs in 2026, around £100 an hour, with typical fees for common jobs: calculations for a beam over a knocked-through wall, an extension design, a structural survey. A consumer body's figures, so treat the hourly rate as indicative and the list of what needs an engineer at all as the useful part.
  3. 3technicalstrong locallyMinistry of Justice, guidance.RN-KWRC49The Civil Procedure Rules on expert evidence; the rule on restricting expert evidence says no party may call an expert or put in an expert's report without the court's permission.
  4. 4technicalstrong locallyMinistry of Justice, guidance.RN-4CFNI6Practice Direction 35 on the form and content of expert reports; paragraph 3.3 requires the report to be verified by a statement of truth in a set wording.
  5. 5technicalstrong locallyMinistry of Justice, guidance.RN-J6RSESPractice Direction 27A on the small claims track; paragraph 7.3 caps the experts' fees one party can be ordered to pay the other at £750 for each expert.
  6. 6technicalvery strongMinistry of Justice, a government page.RN-53VCSFCPR Part 27 is the procedure that applies once a claim against a builder is allocated to the small claims track under Part 26. The track normally takes claims of no more than £10,000, with personal injury damages capped at £1,000 and housing disrepair claims where the repairs are valued at £1,000 or less. The costs rule is the point homeowners most need to understand: the court may not order one party to pay another's costs, fees and expenses except for the fixed issue costs, court fees actually paid, witness travel and overnight expenses, a capped sum for a party's or witness's loss of earnings, a capped experts' fee, and costs awarded against a party who has behaved unreasonably, assessed summarily. Those restrictions survive a later reallocation off the small claims track unless the court orders otherwise, so winning does not usually mean recovering solicitors' fees.

  1. Steel Beam & RSJ Calculations UK, The Beam Doctor, accessed 30 September 2026. Priced at 2026-09, so no calibration is needed. thebeamdoctor.co.uk

  2. Structural Engineer Costs In 2026, HomeOwners Alliance, accessed 30 September 2026. Priced at 2026-09 and left there. hoa.org.uk

  3. Civil Procedure Rules Part 35: Experts and assessors, Ministry of Justice, accessed 30 September 2026. justice.gov.uk

  4. Practice Direction 35: Experts and assessors, Ministry of Justice, accessed 30 September 2026. justice.gov.uk

  5. Practice Direction 27A: Small claims track, Ministry of Justice, accessed 30 September 2026. justice.gov.uk

  6. Civil Procedure Rules Part 27: The small claims track, Ministry of Justice, accessed 30 September 2026. justice.gov.uk