Methodology

How the calculator derives GIFA from pupil count, applies BCIS regional factors and phase multipliers, and layers Spec21, BNG, FF&E, fees and abnormals into the all-in figure.

GIFA derivation

BB103 sets mainstream area at around 6.8 m²/place for primary, 9.6 m²/place for secondary[BB103]. BB104 sets SEN at around 19 m²/place[BB104]. Sixth-form at 8 m²/place; nursery at 5.5 m²/place. These are planning anchors; actual GIFA is set by the area schedule on a real scheme.

Base £/m² rates (BCIS Q2 2026 + LGA cohort)

Primary £2,415/m²; secondary £2,640/m²; SEN £3,180/m²; sixth-form £2,720/m²; nursery £2,295/m². England-average new-build base, before regional factor[BCIS][LGA].

Regional location factors

11 BCIS regions, factors 0.92 (North East) to 1.13 (London)[BCIS]. Applied as a straight multiplier on the base rate. Factors are derived from contractor returns across all building types, so they are a planning anchor not a schools-only multiplier.

Project-type multipliers

New build: 1.00.
Expansion: 0.92 (receptor school absorbs shared accommodation).
Refurbishment: 0.62 (whole-school median per LGA cohort)[LGA].
CIF condition package: 0.45 (roof + boiler + windows lump).

Build-method multipliers

Traditional: 1.00. Volumetric modular: 0.96. The headline cost delta is small; programme certainty is the larger commercial benefit on a modular scheme[LGA].

Uplifts

Net Zero Spec21: +10% on works[Spec21].
BNG: +1.5% on works (typical school site with on-site delivery)[BNG].
FF&E: +8% on works (planning median; SEN runs 10-14%)[LGA].
Professional fees: +10% on works (ESFA CIF cap)[CIF].
Abnormals: +5% on works (default; raise on confirmed asbestos / RAAC / contaminated land)[NAO].

Assumptions and limitations

The calculator is a planning anchor, not a tender estimate. It assumes a notional plot without acquisition cost, statutory fees outside the ESFA cap, finance costs or inflation beyond Q2 2026. For tender-stage certainty, instruct a chartered QS. See disclaimer.