For Planners & Developers
A formal Financial Viability Assessment (FVA) requires multiple data inputs assembled by a RICS-qualified valuer. The most time-consuming part — residential market comparables — is exactly what we do. Instantly. For all 33 London boroughs. Cited to Crown copyright data. The remaining inputs are specialist work that no AI tool replaces — but we make sure the market evidence baseline is already done before your valuer begins.
| FVA Requirement | Our coverage | Source / what to use |
|---|---|---|
|
GDV — Gross Development Value inputs · We cover this in full
|
||
|
Residential sale prices — median
Comparable completed sales by property type in the local market. The primary input for calculating what a completed development is worth.
|
Covered |
We provide this. Median prices by borough, postcode district, and property type from 1.76M LR transactions (2010–present).
HM Land Registry PPD |
|
Lower quartile prices (PPG §021 standard)
The entry-level market benchmark required by Planning Practice Guidance for affordable housing need calculations. More important than median for viability work.
|
Covered |
We provide this. Lower quartile (25th percentile) across all property types, alongside median — per borough and postcode.
HM Land Registry PPD |
|
New-build vs resale price differential
The premium new-build commands over comparable second-hand stock. This is the core margin signal for viability — if no premium exists, S106 contributions compress developer return.
|
Covered |
We provide this. New-build vs resale median and lower quartile comparison, with transaction counts per category. No official benchmark % — ours is as defensible as any source.
HM Land Registry PPD (tenure flag) |
|
Market depth — transaction volume
Inspectors and valuers assess how many comparables exist. Thin markets (fewer than ~50 transactions/year) reduce the statistical reliability of price evidence.
|
Covered |
We provide this. Annual transaction counts by borough and postcode, with year-on-year trend.
HM Land Registry PPD |
|
Price growth trend (5-year and 10-year)
Required to project GDV at completion for longer build-out programmes. The PPG standard is period % change; CAGR is supplementary.
|
Roadmap |
Feature 4 — to be developed. Will provide 5-year and 10-year % change with conservative / central / optimistic scenario range, framed as a statistical indicator (not a forecast).
HM Land Registry PPD |
|
Cross-boundary comparables
For sites near borough boundaries, or Statements of Common Ground under NPPF §24 (Duty to Cooperate), evidence must be consistent across LPA areas from the same dataset.
|
Roadmap |
Feature 2 — to be developed. Will provide side-by-side comparison of up to 5 boroughs simultaneously — same dataset, same methodology, directly comparable for Statements of Common Ground under NPPF §24.
HM Land Registry PPD · All 33 boroughs |
|
Affordability context · We provide useful indicators; the PPG standard requires additional data
|
||
|
Affordability ratio
PPG Standard Method uses the ONS 5-year average workplace-based median affordability ratio (ASHE earnings data). Required for housing target calculations.
|
Partial |
We provide price band distribution — the % of transactions in each price bracket (e.g. under £250k, £250k–£500k) for the reference year. This shows what share of the market sits in each affordability tier and is useful context for viability discussions.
To reach the PPG standard you also need: the ONS House price to residence-based earnings ratio dataset — workplace-based median earnings from ASHE, 5-year average, published at local authority level. We provide: LR price band distribution · PPG standard also needs: ONS ASHE earnings data |
|
Market access analysis
PPG §021 requires deriving the number of households unable to afford market housing — calculated from the lower quartile price, ASHE workplace-based median earnings, and MHCLG household projections.
|
Not covered |
We do not provide this. The full calculation requires ASHE workplace-based median earnings and MHCLG household projections — neither is in our Land Registry dataset.
We supply the lower quartile price input. The rest of the calculation must be done separately using ONS ASHE data and the MHCLG 2021-based household projections. We provide: LR lower quartile price only · Also needed: ONS ASHE + MHCLG household projections |
|
RICS specialist inputs · Outside scope of market data — requires qualified professionals
|
||
|
Build costs (construction)
The PPG mandates BCIS (Building Cost Information Service) as the reference standard for construction costs in viability assessments.
|
Specialist |
Use BCIS for benchmark build costs. Quantity surveyor report recommended for site-specific abnormal costs.
|
|
Benchmark Land Value (EUV+)
The EUV+ approach is mandatory under PPG for establishing Benchmark Land Value. This requires a site-specific assessment of Existing Use Value plus a landowner premium.
|
Specialist |
Requires a RICS-qualified valuer. PPG explicitly states: price paid for land is not a relevant justification for failing to meet policy requirements.
|
|
Developer return assumption
PPG recommends 15–20% of GDV as a plan-making assumption. Site-specific FVAs require market-based justification for the return assumption used.
|
Specialist |
PPG §019 guidance applies. Use RICS-qualified valuer for site-specific return assumptions.
|
|
Finance costs & programme
Interest costs on development finance over the build programme. Varies by scheme size, lender terms, and construction timeline.
|
Specialist |
Site-specific. Requires development finance market evidence from the valuer.
|
|
RICS-qualified author
Since the RICS Professional Standard (effective 1 September 2019, reissued April 2023), a Financial Viability Assessment submitted with a planning application must be prepared or reviewed by a RICS member.
|
Specialist | |
|
Roadmap · Features in development — some require data partners to complete
|
||
|
S106 / CIL schedule lookup
Each LPA publishes its own Community Infrastructure Levy rates and S106 obligations. Currently scattered across 33 borough websites.
|
Roadmap |
Planned: structured CIL/S106 rate database for all 33 London boroughs, integrated into the planning evidence output. Currently: check each LPA website directly.
|
|
ONS earnings data integration
ASHE (Annual Survey of Hours and Earnings) workplace-based median earnings by local authority — the PPG-standard denominator for affordability ratios.
|
Roadmap |
Planned: integrate ONS ASHE data to produce PPG-standard affordability ratios (not just price-to-estimated-income indicators). Currently: use the ONS House price to residence-based earnings ratio dataset.
|
|
EPC & floor area data
MHCLG's own land value appraisal tools use £/sqm values derived from EPC floor area data combined with Land Registry prices — a more precise GDV basis than bedroom-type alone.
|
Roadmap |
Planned: link EPC floor area data to LR transactions for £/sqm pricing — the same methodology used by MHCLG in its Land Value Estimates for Policy Appraisal (2023).
|
What geographic level does this work at?
No official planning guidance mandates a specific geographic unit for market comparable evidence. In London practice, site-specific FVA valuers use postcode district (e.g. SW11) as the standard — large enough for statistical reliability, small enough to reflect genuine local price variation. We follow the same convention.
| Level | Example | Used for in planning practice | Our support | Official source |
|---|---|---|---|---|
|
Postcode district
The standard FVA unit in London
|
SW11, E8, N1 | Site-specific FVA GDV comparables. The primary geographic unit used by London valuers (JLL, Savills, Montagu Evans) when assembling comparable sales evidence for S106 viability submissions. | Primary | HMLR Price Paid Standard Reports · GLA Development Viability LPG (2023) |
|
Borough
Fallback when volume is low
|
Wandsworth, Hackney | Plan-making viability typologies. HMLR HPI indexation in GLA S106 review mechanisms. PPG Standard Method affordability ratios (ONS publishes at local authority level). | Fallback | PPG para 2a-004-20241212 · HMLR UK HPI (borough series) · GLA Development Viability LPG App. 1 |
|
Postcode sector
Higher precision, same data
|
SW11 1, E8 3 | Site-specific FVA when the development site is in a distinctly priced micro-location (e.g. riverside vs inland Battersea) and transaction volume supports the narrower geography (typically ≥ 30 sales/year). | Roadmap | We currently aggregate to postcode district (outward code) only. Sector-level queries are on the roadmap — the raw HMLR data supports this level. |
|
MSOA
~5,000–15,000 people
|
E02000887 | ONS-published house price statistics for HNA affordability analysis. ONS HPSSA Dataset 2 publishes median prices at MSOA level quarterly. Each London MSOA sees ~30–150 transactions per year. | Future | ONS HPSSA Dataset 2 (median by MSOA, quarterly rolling) · PPG Housing Needs Assessment |
|
Ward
~9,000–15,000 people (London)
|
Battersea Park ward | GLA London Living Rent benchmarks — the GLA uses ward-level house prices to set LLR rents, varied by up to 20% from the borough median. Not the standard unit for FVA comparable evidence. Ward boundaries do not align with buyer search patterns or postcode areas. | Not in scope | GLA Affordable Housing LPG (2023) para 3.2.2 · Custom LR extract — not an ONS published series |
Volume check: When a postcode district has fewer than 30 transactions in the last 12 months, the tool automatically falls back to borough-level figures and notes this in the output. No official guidance sets a minimum transaction count — 30 is the commonly applied statistical reliability threshold in planning evidence practice.