Khalim Conn-Kowlessar a9632937d5 fix(ventilation): use lodged extract-fan count when known, not max(lodged, age default) (RdSAP 10 §4.1 Table 5, PDF p.28) ... Table 5 reads "Number of extract fans if known; if number is unknown: [age-band default]" — the default is an UNKNOWN-fallback, NOT a floor. The cascade applied `max(lodged, table_5_default)`, flooring a genuinely-lodged count up to the age-band minimum: e.g. an age H-M dwelling lodging 2 extract fans was billed at the 6-8-room default of 3, over-counting ventilation line (8) and the heat-loss coefficient. Fixed to `lodged if lodged > 0 else default` (a lodged 0 is the Elmhurst/RdSAP "unknown" form → default; any positive count is taken literally). Surfaced by Khalim's Elmhurst stress worksheet (simulated case 46): this was its last ventilation residual — our Jan effective ACH 9.14 -> 9.0748 (exact match to the accredited worksheet), SAP 29 -> 30 = Elmhurst, cost £1496 vs £1493. Corpus IMPROVED: within-0.5 71.6% -> 72.5%, MAE 0.819 -> 0.815 (the max-flooring over-counted ventilation on every cert lodging fans below its age default). Floor ratcheted 0.71 -> 0.72. pyright not installed locally. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>		2026-06-21 06:22:26 +00:00
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__init__.py	refactor: lift-and-shift packages/domain/src/domain/sap → domain/sap10_calculator	2026-05-26 12:22:37 +00:00
cert_to_inputs.py	fix(ventilation): use lodged extract-fan count when known, not max(lodged, age default) (RdSAP 10 §4.1 Table 5, PDF p.28)	2026-06-21 06:22:26 +00:00