Small sites, 1 to 9 units (NPPF preset)

NPPF Dec-2025 small-sites threshold. BNG exemption to 1 sept 2026 transition; CIL minor-development relief.

Preset defaults

  • Units: 4
  • GIA per unit: 870 sqft
  • NIA ratio: 88%
  • Build cost: 2,300 £/sqm
  • Professional fees: 11%
  • Contingency: 7.5%
  • s106 / CIL / BNG per unit: £0
  • Finance rate: 9.75%
  • Duration: 12 months
  • Target PoC: 20%

What this preset is for

NPPF Dec-2025 small-sites threshold. BNG exemption to 1 sept 2026 transition; CIL minor-development relief.

Small-sites threshold

  • NPPF Dec-2025: small sites typically defined as 1 to 9 dwellings (council varies).
  • BNG exemption for small sites transitions; check the latest commencement guidance before relying on it.

CIL minor-development relief

  • Schemes that fall below the CIL minimum-floor-area threshold (100 sqm net additional floorspace, 1 dwelling) qualify for relief.
  • Lawful prior development must be netted off the GIA calculation.

Open in workbench

Inputs
MAX LAND BID£176,056At 20% profit on cost, 4 units, 870 sqft GIA each.
MARGINAL
GDV£1,301,520
Build cost£743,596
Prof fees£81,796
s106/CIL/BNG£0
Contingency£61,904
Finance interest£43,256
Target profit£186,110
Total costs (excl land)£930,551
Senior debt @ LTGDV£845,988
PoC17.6%
PoGDV15.0%
LTC76.4%
Sensitivity (PoC %)
Build -5%Build +5%Build +10%Build +15%Build +20%
GDV -15%19%13%8%3%-1%
GDV -10%18%20%14%9%5%
GDV -5%18%19%20%16%11%
GDV 0%17%18%19%20%17%
GDV +5%16%18%18%19%20%

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.

National Planning Policy Framework, Dec 2025 revision· Dec 2025Appraisal model reviewed by Oliver Wakefield-Smith (data integrity) with chartered-surveyor (MRICS) and CTA tax review. No affiliate links.