Model/domain
Khalim Conn-Kowlessar c10881ae7a feat(heat-transmission): door to unheated corridor uses Table 26 U=1.4 on the sheltered wall
A door opening to an unheated corridor/stairwell takes U=1.4 W/m²K (RdSAP 10
Table 26, p.51 — any age band) instead of the 3.0 external-door default, and
its area deducts from the SHELTERED wall, not the main wall (RdSAP §3.7,
p.18: "the door of a flat/maisonette to an unheated stairwell or corridor
... is deducted from the sheltered wall area"). The cascade previously
billed every door at the external U on the main wall.

Signal: a SHELTERED alternative wall (`is_sheltered`, the RdSAP §5.9
wall-to-unheated-corridor surface, already modelled) is the evidence that
the dwelling is accessed via an unheated corridor, so one lodged door opens
to it. `_corridor_door_count` returns 1 when a sheltered alt wall is present
and >=1 door is lodged, else 0 — so the door channel is unchanged for every
non-corridor dwelling (houses, exposed-gable flats). `heat_transmission_
from_cert` gains a `corridor_door_count` param (default 0): it splits the
door area into external (main wall, age-default U) + corridor (sheltered
alt wall, U=1.4), threading the corridor door's area into that wall's
opening deduction and billing it at 1.4.

Validated on TWO faithful worksheets: simulated case 34 (cert 001431
storage flat — doors 8.14 exact, fabric 207.47 ≈ ws 207.48) and the
long-standing worksheet-harness diverger cert 2474 (−0.87 → −0.32, the
"space-demand thread" was the dropped corridor door). The worksheet harness
is now 47/47 with ZERO divergers.

API SAP gauge: 57.6% → 60.0% within 0.5; mean|err| 1.185 → 1.167; signed
−0.165 → −0.115 — ~22 sheltered-corridor flats were a systematic gap.
Regression gate green (3 pre-existing fails unrelated); pyright net-zero.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-11 08:03:06 +00:00
..
addresses standardist Address 2026-05-22 10:13:32 +00:00
data_transformation moved classifier data transformation to an easy one 2026-06-01 14:53:34 +00:00
epc Remove EPC and asset_list changes unrelated to SAL handler 2026-06-01 16:39:09 +00:00
fuel_rates feat(fuel-rates): FuelRates snapshot + repository foundation (ADR-0014) 2026-06-02 09:29:07 +00:00
geospatial feat(geospatial): GeospatialRepo — OS Open-UPRN coordinate lookup (#1131) 2026-06-01 16:28:48 +00:00
property feat(property): Property aggregate + PropertyRepository (#1132) 2026-06-01 16:28:48 +00:00
property_baseline feat(baseline): sap_code_to_fuel normalizes via the calculator's own helper 2026-06-05 18:59:25 +00:00
sap10_calculator feat(heat-transmission): door to unheated corridor uses Table 26 U=1.4 on the sheltered wall 2026-06-11 08:03:06 +00:00
sap10_ml test(efficiency): lock solid-fuel room-heater space eff to Table 4a column (B) 2026-06-10 11:09:12 +00:00
tasks added postcode splitter rewrite to ddd 2026-05-19 16:35:09 +00:00
postcode.py get rid of comments 2026-05-20 13:21:11 +00:00