GDV.calculator

Residual Land Value Calculator

The residual method back-solves land value from GDV. Costs (build, fees, s106, CIL, BNG, SDLT, contingency, finance) and target developer profit are subtracted from GDV. What remains is the max bid for the land before SDLT is grossed back. Workbench below applies a 5 percent SDLT-on-land assumption by default.

Formula

Residual land value = (GDV minus total costs minus target profit) divided by (1 + SDLT on land rate).

SDLT non-residential rates apply where bare land is bought; 5 percent additional-dwellings surcharge applies when the buyer is a company or already owns residential property. Use the SDLT line on the workbench.

Developer return

PPG-Viability Dec-2025 cites 17.5 percent profit on GDV as the working benchmark for unobjectionable schemes. Lenders typically reference 20 percent profit on cost; the two are not interchangeable.

Sensitivity matters

Run the GDV down 10 percent and build up 10 percent at once. If the deal aborts in that quadrant the residual is fragile and your land bid should fall further.

Inputs
MAX LAND BID£106,489At 20% profit on cost, 9 units, 950 sqft GIA each.
MARGINAL
GDV£3,088,688
Build cost£1,826,937
Prof fees£219,232
s106/CIL/BNG£108,000
Contingency£161,563
Finance interest£164,996
Target profit£496,146
Total costs (excl land)£2,480,729
Senior debt @ LTGDV£2,007,647
PoC19.4%
PoGDV16.2%
LTC77.6%
Sensitivity (PoC %)
Build -5%Build +5%Build +10%Build +15%Build +20%
GDV -15%11%1%-3%-7%-11%
GDV -10%18%7%2%-2%-6%
GDV -5%19%13%8%4%-1%
GDV 0%19%19%14%9%5%
GDV +5%18%19%19%14%10%

Cells show profit-on-cost percentage at each GDV stress / build-cost shock pair. Cells below your target PoC turn amber-warm; cells below 10 percent abort.

Planning Practice Guidance: Viability· Dec 2025Appraisal model reviewed by Oliver Wakefield-Smith (data integrity) with chartered-surveyor (MRICS) and CTA tax review. No affiliate links.