Author: Oliver Wakefield-Smith, Founder Digital Signet. Reviewed against DfE Sustainability Strategy (Mar 2025) and Education Estates Strategy (Feb 2026). Verified 22 June 2026.
Five questions a bursar or estates director should be able to answer before signing a consultant. Each answer is sourced to the underlying DfE, Salix or Ofgem guidance via the [S] citation register.
At 2026 anchors, school net zero cost is £300k to £3m per site, ex-VAT. A typical primary (1,800 m2, 1945-1976) sits near £480k. A typical secondary (7,500 m2) sits near £2.4m. PSDS Phase 4 plus Salix CIF can offset 60 to 100 per cent of the ceiling for the priority cohort.
PSDS and CIF can be sequenced on the same building if the funded scope does not overlap. Concurrent funding of the same kit is prohibited. A common pattern is CIF-funded condition replacement (windows, roof) followed by PSDS-funded ASHP retrofit once fabric is brought to target U-values.
DfE expects every setting in England to have a Climate Action Plan and a named Sustainability Lead by the start of the September 2026 academic year. The plan must cover the four pillars: Decarbonisation, Adaptation and Resilience, Biodiversity, Climate Education.
Heat pumps are viable in pre-1944 stock provided fabric is upgraded first. Without fabric uplift, heat-loss coefficients near 85 to 95 W/m2 drive oversized heat-pump plant, trigger DNO upgrades and undermine the Salix payback gateway. With fabric uplift to 0.18 W/m2K walls and 0.13 roofs, the heat pump sizes down to a sensible footprint.
Where the per-school ceiling exceeds the available stacked grant, the residual is funded by trust capital, by Salix Recycling Fund interest-free loans, or by a PPA-financed solar element. The worksheet returns the net of grant figure so the trust can size the residual ask accurately.