Sizing a Neighbourhood Cold and Warm Refuge: A Design Rule per 1,000 Residents for Floor Area, Thermal Load and 72-Hour Backup Energy

A sizing model for heated and cooled public refuges, stated per 1,000 residents, derived from population, vulnerable fraction, uptake, overnight occupancy density, envelope and ventilation heat transfer, internal gains and event duration. Base case (vulnerable fraction 0.25, uptake 0.80): 200 occupants plus 16 staff require 4.68 m2 gross per person present, 1,010.0 m2 in total. For a 72-hour heatwave blackout at 40 C in a good building, peak cooling is 51.87 kW thermal, peak electric load 22.48 kW, and the backup-energy bound with reserve is 1,720 kWh or 491 litres of generator diesel, at $1,748.91 capital cost per protected resident; in a poor building cooling rises to 75.99 kW. For a 72-hour winter outage at -15 C, peak heating is 7.44 kW in a good building and 43.70 kW in a poor one. No single typical public building meets the area rule: a 600 m2 school gymnasium covers 59.4% of the required area. SIMULATED, NOT MEASURED.