RICS COSTMODELLING.COM · BENCHMARK COMPARISON · MARCH 2026
The claimant's repair cost figures align closely with published RICS benchmarks for Outer London.
RICS costmodelling.com is the authoritative industry source for UK construction cost benchmarks. The data below shows that the claimant's revised assessment of £329,523 (£1248/m²) sits within the RICS published range for Outer London — and is in fact below the lower quartile. The insurer's counter-assessment of £109,920 (£416/m²) falls far outside this range.
Key Finding
The claimant's revised figures closely match the RICS published range — and are independently corroborated by a separate contractor tender.
The revised repair cost assessment of £329,523 equates to £1248/m². This sits below the RICS lower quartile of £1890/m² for Outer London. An independently obtained contractor tender from HJ Building & Construction Ltd came in at £324,999 (£1231/m²) — within 1.4% of the QS assessment — providing direct market validation of the figures.
Insurer's Position
AXA's figure is 67% below the RICS lower quartile.
The insurer's counter-assessment of £109,920 equates to £416/m². This is £1474/m² below the RICS lower quartile — a shortfall of 78% against the industry's own lowest published benchmark.
The chart below places every cost figure in context against the RICS published range for Outer London. The claimant's figures cluster within the lower end of the RICS range. The insurer's figure stands alone, far below the industry minimum.
RICS Median (Outer London)
Industry benchmark — 50th percentile
RICS Lower Quartile (Outer London)
Industry benchmark — 25th percentile
Urbanist Architecture — Extensive Refurb
Outer London, 2025
Urbanist Architecture — Moderate Refurb
Outer London, 2025
Original Repair Cost Assessment
Charles Ramsden Ltd (MRICS) — June 2024
Revised Repair Cost Assessment
Charles Ramsden Ltd (MRICS) — post Oct 2024
Independent Contractor Tender
HJ Building & Construction Ltd
AXA Internal Review
Terry McKane-Slaughter, AssocRICS — Nov 2024
Revised QS Assessment
£329,523
£1248/m² · Charles Ramsden Ltd (MRICS) · SPONS rates
· Prepared by MRICS-qualified Chartered Quantity Surveyor
· 108 priced line items using SPONS industry rates
· Reduced from original £477,227 following joint inspection
HJ Building & Construction Ltd — Tender
£324,999
£1231/m² · Independent contractor · Market rates
· Independently obtained — no connection to QS firm
· Includes 20% preliminaries, 12% O&P, 5% contingency
· Differs from QS assessment by just £4,524 (1.4%)
The fact that an independently obtained contractor tender — with no connection to the QS firm — arrived at £324,999 against the QS assessment of £329,523 is a difference of just £4,524 (1.4%). This level of agreement between two entirely independent sources provides strong market validation that the assessed figures are accurate and commercially realistic for this property and location.
All figures shown per m² and as a total for 220m². The "vs Claimant" column shows how each figure compares to the revised QS assessment.
| Source | Per m² | Total (220m²) | vs Claimant |
|---|---|---|---|
RICS costmodelling.com — Lower Quartile | £1890 | £415,800 | -34% |
RICS costmodelling.com — Median | £2430 | £534,600 | -49% |
Urbanist Architecture — Moderate Refurb | £1591 | £350,020 | -22% |
Urbanist Architecture — Extensive Refurb | £2091 | £460,020 | -40% |
Revised Repair Cost Assessment (MRICS) | £1248 | £329,523 | — |
Independent Contractor Tender (HJ Building) | £1231 | £324,999 | -1% |
AXA Internal Review (AssocRICS) | £416 | £109,920 | -67% |
Summary: The claimant's revised assessment of £329,523 (£1248/m²) is 34% below the RICS lower quartile, and is independently corroborated by a contractor tender within 1.4%. The insurer's figure of £109,920 (£416/m²) is 78% below the RICS lower quartile — a position that cannot be reconciled with published industry data.
costmodelling.com/building-costs
The authoritative RICS construction cost modelling database. Provides UK-wide and regional benchmarks based on extensive industry data, updated annually. The lower quartile figure of £1890/m² represents the 25th percentile of actual project costs in Outer London — meaning 75% of comparable projects cost more than this.
urbanistarchitecture.co.uk
Professional architecture firm specialising in London projects. Cost data based on actual project experience with builders in London, updated for 2025 market conditions. Moderate refurbishment: £1591/m². Extensive refurbishment: £2091/m². Given the scale of water damage at this property, the extensive refurbishment category is the more appropriate comparator.