Zones, electrical heat sources, windows with ventilation, wind exposure and recovery, and exchange between adjacent zones, all observational. docs/MODEL.md documents the equations, units, coefficient meanings, priors and bounds, learning conditions, forecast assumptions, validation method and results, and limitations. README gains a configuration guide for zones, heat sources and windows, the new diagnostics and the accuracy comparison against the base model. CHANGELOG has upgrade notes (config entry version 3, rollback needs the backup, renamed Status attributes). ROADMAP marks the Milestone 2 items now covered; AUDIT records the design decisions and evidence. AGENTS.md lists the new modules and the convention that new model terms start at zero and must beat the base model out of sample before being relied on. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>