Blueprint: Passive Radiative-Cooling Roof — Build Specification

DESIGN BLUEPRINT — SIMULATED, NOT MEASURED — NOT BUILT, NOT LOAD-TESTED. Build specification derived from Aldred, 'A Passive Radiative-Cooling Roof Assembly for Heat-Wave Housing' (DOI: 10.5281/zenodo.24108520). Specifies a barium-sulfate-class sky-window coating (reflectance 0.95, emissivity 0.95) over 6 mm fibre-cement board with reflective foil underlay for a 16 m2 room, with optional 200 kg water storage: assembly build-up, bill of materials (USD 288 per room), construction sequence, computed operating envelope (daily-mean reduction 3.61-3.75 K vs a dark roof; 0.79-0.87 K vs a white roof), the humid-case collapse of sub-ambient cooling (4.8 W/m2, 0.4 K at peak sun), tolerances, failure modes, maintenance, and independent verification items. All performance numbers are from the source paper; no hardware was built or tested.