Model/datatypes
Khalim Conn-Kowlessar 1f266d0282 Bill metal-framed API windows on the Table 24 metal U-column 🟩
On the gov-EPC API path a window's metal frame was unrepresentable: both
transmission tables were frameless (U_pvc, g, 0.70), so a cert lodging a metal
frame (pvc_frame:"false", RdSAP input 6-5) was billed at the PVC/wooden U and
frame factor 0.70 — over-rating metal-framed dwellings.

Add the RdSAP 10 Table 24 metal U-column (PDF p.50-51; mirrors u_window's metal
values) and a pvc_frame dimension to _api_glazing_transmission: an explicit
"false" routes the window to the metal U + SAP 10.2 Table 6c frame factor 0.8;
"true"/None/other keep the PVC column + 0.70, so no PVC cert regresses.
Secondary glazing keeps its frame-independent U (only FF changes). Wired into
_api_sap_window and _api_sap_roof_window (both full-schema, lodge pvc_frame);
the reduced-field path has no pvc_frame and is unchanged.

Spec: RdSAP 10 Table 24 metal column, SAP 10.2 Table 6c, RdSAP input 6-5 (p.80).
Corpus: within-0.5 80.6% -> 81.0%, MAE 0.578 -> 0.571. Cert 21067296
68.60 -> 66.96 (toward lodged 67). Closes #1667.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-22 12:54:47 +00:00
..
epc Bill metal-framed API windows on the Table 24 metal U-column 🟩 2026-07-22 12:54:47 +00:00
__init__.py further breaking up code 2023-07-20 12:24:34 +01:00
address_match.py refactor(address2uprn): name the match/decision return types; rename helper 2026-07-07 16:00:00 +00:00
datatypes.py further breaking up code 2023-07-20 12:24:34 +01:00
enums.py completed build of new demo portfolio - some fixed required still 2023-11-20 14:42:16 +00:00